ALERTA BIBLIOGRÁFICA DE LA PRODUCCIÓN CIENTÍFICA DEL COLEGIO DE POSTGRADUADOS, No. 60, FEBRERO DE 2015

ALERTA BIBLIOGRÁFICA DE LA PRODUCCIÓN CIENTÍFICA DEL COLEGIO DE POSTGRADUADOS, EN REVISTAS INDIZADAS EN LA COLECCIÓN PRINCIPAL DEL ISI WEB DE LA CIENCIA Y EN SCOPUS, No. 60, FEBRERO DE 2015

Angel Bravo Vinaja

Recursos y Servicios de Información Científica y Tecnológica, RESDICYT-COLPOS. Campus San Luis Potosí. Iturbide 73, Salinas de Hidalgo, S. L. P. 78622, México Tel. +52(496) 96 30240 ext. 4039. abravo@colpos.mx

 

Se muestran 84 registros de documentos en los que participan como autores personal académico del Colegio de Postgraduados, 45 se obtuvieron de la Colección Principal del ISI Web de la Ciencia (WOS) de la empresa Thomson Reuters, específicamente del Science Citation Index Expanded (SCIE) y Social Sciences Citation Index (SSCI) y 39 de SCOPUS de la Empresa Elsevier.

En la parte I se muestran los documentos indizados en la Colección Principal del Web de la Ciencia y en la parte II los documentos indizados en SCOPUS, ambos listados se presentan en orden alfabético por apellido del primer autor. Los registros bibliográficos se presentan de acuerdo a la norma ISO 690 inglés, iluminando el título del documento en color azul.

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Parte I. Documentos indizados en la Colección Principal del Web de la Ciencia del 15 de diciembre de 2014 al 28 de febrero de 2015

ACEVES, O. J., ORTEGA, C. M. E., MENDOZA, M. G., HERRERA, H. J., ZETINA, C. P. and BARCENA GAMA, R., 2014, Nutritional Evaluation of Wheat Straw Upgraded by Pleurotus ostreatus in Growing Lambs. Animal Nutrition and Feed Technology. September 2014. Vol. 14, no. 3, p. 593–599. DOI: http://dx.doi.org/10.5958/0974-181X.2014.01361.4.

Wheat straw left after harvesting of edible mushroom Pleurotus ostreatus was evaluated as feed for growing lambs. Twenty four weaned lambs (25.75 +/- 5 kg) were randomly assigned to two treatments: 70% of wheat straw, either raw (US) or upgraded by Pleurotus ostreatus (TS) plus 30% of a concentrate mixture. Lambs were fed the diets for 60d. Feed intake, BW gain and feed conversion (FC) were measured. In situ digestibility of DM, NDF, ADF, and in vivo DM digestibility were also evaluated. The results showed no difference (P>0.05) in feed intake (1.65 and 1.59 kg day(-1) for US and TS, respectively), with a lower (P<0.05) BW gain for TS (4.75 +/- 0.406 kg) than for US (6.06 +/- 0.401 kg) accompanying a poorer FC (US 16.91; TS 22.18). In vivo digestibility of DM was similar (P>0.05) for both treatments (76.43% US, 76.16% TS), as were the data on in situ digestibility of DM, NDF, and ADF after 12, 24, 36, 48, and 72h of incubation in the rumen. In conclusion, it could be said that wheat straw treated by Pleurotus ostreatus did not improve its nutritional value when fed to growing lambs.

AGUAS-ATLAHUA, Aristarco, GARCIA-PEREZ, Eliseo, RUIZ-ROSADO, Octavio and TRINIDAD-SANTOS, Antonio, 2014, FRUIT QUALITY OF LYCHEE (Litchi chinensis Sonn.) PRODUCED IN VERACRUZ STATE, MEXICO. Revista Fitotecnia Mexicana. December 2014. Vol. 37, no. 4, p. 373–380.

Lychee (Litchi chinensis Sonn.) is a fruit originating from China and Vietnam which is cultivated in Mexico also, and Veracruz is cultivated with “Mauritius” and “Brewster” cultivars and it is the main state for the national and international markets. The aim of this research was to evaluate the physical and chemical characteristics of lychee fruits produced in six orchards located at the central and northern regions of the state of Veracruz. For this study 4 kg were sampled per each orchard, from which 40 fruits were randomly selected for quality evaluation. The variables measured were: length, diameter, firmness, weight of fruit and its components (e.g. pulp, peel and seed), total soluble solids, titratable acidity, and pericarp color. The “Mauritius” fruits varied in quality amongst orchards. The Lechuguillas orchard showed the biggest fruits with 35.1 mm length, 21.2 g of total weight and 16.8 g of pulp weight. Furthermore, fruits of this site had low acidity, acceptable peel color and high content of total soluble solids.

AGUILAR-DORANTES, Karla, MEHLTRETER, Klaus, VIBRANS, Heike, MATA-ROSAS, Martin and ESQUEDA-ESQUIVEL, Valentin A., 2014, Repeated Selective Cutting Controls Neotropical Bracken (Pteridium arachnoideum) and Restores Abandoned Pastures. Invasive Plant Science and Management. December 2014. Vol. 7, no. 4, p. 580–589. DOI: http://dx.doi.org/10.1614/IPSM-D-13-00062.1.

Neotropical bracken fern invades disturbed forests and burned and abandoned pastures in Latin America, inhibiting the growth of associated vegetation and altering community structure. Cutting of all aboveground vegetation every 6 to 12 mo has proven to be inefficient as a control method. We studied the impact of selective cutting of bracken every 2 mo, shading, and a combination of cutting + shading during 14 mo in a bracken-dominated, abandoned pasture in Veracruz, Mexico. At the end of the experiment, cutting with or without shading drastically reduced bracken cover from >90% to less than 1%, decreased leaf number from 18 to fewer than two leaves per m(2), and depleted bracken leaf biomass. The significant reduction of bracken was correlated with a significant 3.9- to 5.7-fold increase in richness of other plant species. Cutting without shading was the only treatment that significantly reduced rhizome biomass to less than 62% of control plots, whereas cutting + shading was the only treatment to promote a significant increase in both cover and shoot biomass of successional plant species. Selective cutting of P. arachnoideum repeated every 2 mo was more successful than nonselective cuttings repeated at longer intervals, because it removed newly emerging leaves before their complete expansion and supported the recovery and reestablishment of other plant species, which may help to control bracken. Although costs for the first year of selective cutting were twice as much as for nonselective cutting, it may prove less expensive and more efficient than nonselective cutting in the long term.

AGUIRRE-MEDINA, Juan F., MINA-BRIONES, Francisco O., CADENA-INIGUEZ, Jorge, DARDON-ZUNUN, Joni D. and HERNANDEZ-SEDAS, Dante A., 2014, GROWTH OF Cedrela odorata L. BIOFERTILIZED WITH Rhizophagus intraradices and Azospirillum brasilense UNDER NURSERY CONDITIONS. Revista Chapingo Serie Ciencias Forestales Y Del Ambiente. December 2014. Vol. 20, no. 3, p. 177–186. DOI: http://dx.doi.org/10.5154/r.rchscfa.2014.01.001.

Cedrela odorata L. is a species distinguished by the quality of its wood. Cedar established in the field must adapt to changes in resource availability; survival is greater when the root system is associated with microorganisms that improve nutrition and growth. The aim of this study was to evaluate the effect of Rhizophagus intraradices and Azospirillum brasilense on the growth of C. odorata and its nitrogen (N) and phosphorus (P) uptake capacity. Cedar seeds were sown in pots in accordance with the following treatments: control, 15(N)-15(p)-15(K) fertilization, R. intraradices, A. brasilense, R. intraradices + A. brasilense, and R. intraradices + A. brasilense + A. brasilense + 15(N)-15(p)-15(K) fertilization. Morphological and physiological yield variables and root colonization were recorded every 28 days, and N and P contents at the end of the experiment (140 days). In general, R. intraradices promoted greater plant growth (P <= 0.05) of morphological and physiological yield components. The maximum height (97 cm) was recorded in plants with R. intraradices + A. brasilense + 15(N)-15(p)-15(K) fertilization, representing 40 % more height than the control. N and P increased with the inoculation of the microorganisms alone and combined.

ALVAREZ-CASTRO, Nicte V., CORRALES-GARCIA, Joel, HERNANDEZ-MONTES, Arturo, DEL ROSARIO GARCIA-MATEOS, Ma, PENA-VALDIVIA, Cecilia B. and QUIROZ-GONZALEZ, Beatriz, 2014, Development of a snack from xoconostle (Opuntia matudae Scheinvar) sweetened with neotame and its antioxidant capacity. Journal of the Professional Association for Cactus Development. 2014. Vol. 16, p. 15–31.

The xoconostle (Opuntia matudae Scheinvar) is a sour fruit, of which the peel is consumed. It is perishable, but it has a beneficial effect on human health, as recognized popularly in Mexico. The objective of this study was to create a snack of dried xoconostle using neotame, an artificial non-caloric sweetener, to improve flavor. We present (a) a partial chemical characterization of the fruit (total phenolic content (TP) and antioxidant activity (AA)), (b) dehydration techniques (heating by convection and freeze-drying), and (c) sensorial characterization of the final product. The experimental unit was 40 g of fresh xoconostle peel with three replications. The sweetener did not affect dehydration time of convective heat. The sweetened lyophilized xoconostle had lower TP and AA than unsweetened xoconostle. The sensorial analysis showed that lyophilized xoconostle sweetened with neotame (aqueous solution 32 mg L-1) has acceptable flavor and appearance.

ANTUNEZ-OCAMPO, Oscar M., SANDOVAL-VILLA, Manuel, ALCANTAR-GONZALEZ, Gabriel and SOLIS-MARTINEZ, Martin, 2014, AMMONIUM AND NITRATE APPLICATION ON Physalis peruviana L. PLANTS. Agrociencia. December 2014. Vol. 48, no. 8, p. 805–817.

Golden berry (Physalis peruviana L.) is an indeterminate habit plant, during its vegetative growth nitrogen is the nutrient most demanded and usually absorbs it as nitrate. A combination of NH4+ y NO3-, where NH4+ is lower than or equal to 50 % of total nitrogen increases plant growth, only under certain circumstances and this beneficial effect varies across cuhivars, but the response to ammonium in golden berry is not known. Therefore, the objective of this study was to evaluate the morphologic response, fruit yield and quality of Physalis peruviana L. plants in two year-old plants, (re-sprout) and in new plants derived from seed, to the joint application of NH4+ and NO3-. Experiments were carried out in a greenhouse with a completely randomized design and treatments of the first experiment were the result of combining the ratio NH4+/NO3- (0:100, 25:75 and 50:50), and sprout vigor (low, medium and high). In a second experiment new plants derived from seeds were used and with the same ratios NH4+/NO3- used in the first experiment. Results were analyzed using ANOVA and treatment means were compared with the Tukey’s test (p <= 0.05). In re-sprouting plants, the highest values of final height and stem diameter were obtained in plants with high vigor and with the application of 25 % of NH4+ (p <= 0.05), whereas the highest yield was obtained in plants with high and medium vigor, and with 50 and 25 % of NH4+ (p <= 0.05). Neither NH4+/NO3- ratio in the nutrient solution nor the vigor of the re-sprouts affected the concentration of soluble solids or shelf life of the fruits. In plants from seeds there was also not effect of the NH4+/NO3- ratio on plant height, but with 50 % of NH4+ the diameter of stem increased. The higher yields were obtained in plants treated with the ratio 50/50, and the concentration of soluble solids in fruits did not show a clear effect on the ratio NH4+/NO3-, although at 119 d after transplanting the greatest value in fruits of plants treated only with nitrate (0/100) (p <= 0.05) was reached. Thus, the combined application of ammonium and nitrate increases yield but reduces soluble solids in fruit and shelf life and vigor of re-sprouts is neither determinant nor consistent on yield.

ARECE-GARCIA, Javier, LOPEZ-LEYVA, Yoel, GONZALEZ-GARDUNO, Roberto and TORRES-HERNANDEZ, Glafiro, 2014, Evaluation of strategic and selective anthelmintic treatments on Pelibuey ewes in Cuba. Revista Colombiana De Ciencias Pecuarias. December 2014. Vol. 27, no. 4, p. 273–281.

Background: gastrointestinal parasitism is an important limitation for sheep production in Cuba. This situation is worsened by the lack of an effective parasite control strategy. Objective: to assess whether selective and strategic treatments could help achieve a level of control of nematodes similar to systematic drenchings. Methods: an experimental group of 73 Pelibuey ewes was divided into four groups: 1) the Epizoo group (Epizootiological drenching schedule) was dewormed at lambing in the middle of the dry season and at weaning; 2) the FAMACHA (c) group was treated according to the color of ocular mucosa as indicative of anemia (Categories 4 and 5 of the FAMACHA (c) color chart); 3) the Chemical group was drenched every three months; and 4) the control group, in which animals remained untreated unless fecal egg count (FEC) was higher than 1500 eggs per gram of feces or the packed cell volume (PCV) was lower than 15%. FECs, body scorings (BCS), hematocrits and color of ocular mucosa (COM) were evaluated monthly. Results: the control group showed the highest FEC and the lowest PCV. We also observed similar levels of FEC and body condition (BCS) in the Epizoo, FAMACHA (c) and Chemical groups. The PCV in FAMACHA (c) group was the highest, while no differences were found between the other two groups. Hematocrit had a strong negative correlation (-0.41) with FEC. The FAMACHA (c) method allowed a dramatic decrease in anthelmintic use. Conclusions: the obtained results suggest that FAMACHA (c) method could be incorporated as part of an effective parasite control strategy in sheep.

BARCOS ARIAS, Milton Senen, PENA-CABRIALES, Juan J., ALARCON, Alejandro and MALDONADO VEGA, Maria, 2015, Enhanced Pb Absorption by Hordeum vulgare L. and Helianthus annuus L. Plants Inoculated with an Arbuscular Mycorrhizal Fungi Consortium. International Journal of Phytoremediation. 2015. Vol. 17, no. 5, p. 405–413. DOI: http://dx.doi.org/10.1080/15226514.2014.898023.

The effect of an arbuscular mycorrhizal fungi (AMF) consortium conformed by (Glomus intraradices, Glomus albidum, Glomus diaphanum, and Glomus claroideum) on plant growth and absorption of Pb, Fe, Na, Ca, and P-32 in barley (Hordeum vulgare L.) and sunflower (Helianthus annuus L.) plants was evaluated. AMF-plants and controls were grown in a substrate amended with powdered Pb slag at proportions of 0, 10, 20, and 30% v/v equivalent to total Pb contents of 117; 5,337; 13,659, and 19,913mg Pb kg(-1) substrate, respectively. Mycorrhizal root colonization values were 70, 94, 98, and 90%, for barley and 91, 97, 95, and 97%, for sunflower. AMF inoculum had positive repercussions on plant development of both crops. Mycorrhizal barley absorbed more Pb (40.4mg Pb kg(-1)) shoot dry weight than non-colonized controls (26.5mg Pb kg(-1)) when treated with a high Pb slag dosage. This increase was higher in roots than shoots (650.0 and 511.5mg Pb kg(-1) root dry weight, respectively). A similar pattern was found in sunflower. Plants with AMF absorbed equal or lower amounts of Fe, Na and Ca than controls. H. vulgare absorbed more total P (1.0%) than H. annuus (0.9%). The arbuscular mycorrizal consortium enhanced Pb extraction by plants.

BASAVE VILLALOBOS, Erickson, LOPEZ LOPEZ, Miguel A., CETINA ALCALA, Victor M., ALDRETE, Arnulfo and ALMARAZ SUAREZ, Juan J., 2014, Cultural practices in the nursery that affect seedling quality of Enterolobium cyclocarpum. Bosque. 2014. Vol. 35, no. 3, p. 301–309. DOI: http://dx.doi.org/10.4067/S0717-92002014000300005.

Because one of the main problems that Enterolobium cyclocarpum faces in the planting site is the presence of weeds, to grow plants presenting appropriate characteristics that enable them to overcome these adverse conditions during reforestation appears as necessary. Therefore, after evaluating the responses of various morphological and physiological indicators, and a quality test experiment, the effects of three top pruning intensities (no pruning, 25 % and 50 % pruning) and three fertilization regimes (traditional, exponential and conventional) were studied during nursery production. This approach was made based on the fact that top pruning and fertilization in the nursery are cultural practices that improve seedling quality as long as the pruning intensity and fertilization regime are appropriate. There was no synergy between the two practices; however, each factor influenced independently on the indicators evaluated. Top pruning at 25 % and 50 % did not improve the characteristics of E. cyclocarpum. However, the nutrient supply in a conventional way had a favorable effect when compared with other fertilization regimes. The results provided by the quality test established that conventional fertilization allows plants to perform satisfactorily when nutrient availability is limited.

BOYZO-MARIN, J., REBOLLAR-ALVITER, A., SILVA-ROJAS, H. V., CEJA-TORRES, L. F., URIBE-CORTES, B. and MONCAYO-ESTRADA, R., 2014, Botryosphaeria spp. associated with dieback and stem canker of blackberry in Michoacan, Mexico. Phytopathology. November 2014. Vol. 104, no. 11, p. 18–18.

CAMPOS, A. C., ETCHEVERS-BARRA, J., OLESCHKO, K. L. and HIDALGO MORENO, C., 2014, Soil Microbial Biomass and Nitrogen Mineralization Rates Along an Altitudinal Gradient on the Cofre De Perote Volcano (mexico): The Importance of Landscape Position and Land Use. Land Degradation & Development. December 2014. Vol. 25, no. 6, p. 581–593. DOI: http://dx.doi.org/10.1002/ldr.2185.

A study was conducted to examine the responses of microbial activity and nitrogen (N) transformations along an altitudinal gradient. The gradient was divided into three parts. Three areas were sampled: upper part (UP): coniferous forest, corn field, and abandoned corn field; middle part (MP): tropical cloud forest, grassland, and corn field (COL); and lower part (LP): tropical deciduous forest and sugarcane. The results showed that soil microbial biomass carbon (C) and basal respiration were significantly higher in MP and UP than in LP, whereas the microbial quotient (C-mic/C-org) was higher in LP and MP than in UP. The metabolic quotient (qCO(2)) was similar among gradient parts evaluated. Net N mineralization, ammonification, and nitrification rates were higher in UP than MP and LP. We found that in UP, the forest conversion to cropland resulted in no significant differences in microbial activity and N transformation rates between land uses. In MP, microbial biomass C, ammonification, and net N mineralization rates decreased significantly with conversion to cropland, but C-mic/C-org and nitrification were higher in COL. Basal respiration and qCO(2) were significantly lower in COL when compared with other land uses. In LP, lower microbial biomass C, C-mic/C-org, and nitrification rates but higher ammonification and net N mineralization rates were observed in tropical deciduous forest than in sugarcane. No significant differences in basal respiration and qCO(2) were found between uses of LP. Clearly, then, soil organic C is not equally accessible to the microbial community along the gradient studied. Copyright (c) 2012 John Wiley & Sons, Ltd.

CARRILLO-LOPEZ, Luis M., ZAVALETA-MANCERA, Hilda A., VILCHIS-NESTOR, Alfredo, MARCOS SOTO-HERNANDEZ, R., ARENAS-ALATORRE, Jesus, TREJO-TELLEZ, Libia I. and GOMEZ-MERINO, Fernando, 2014, Biosynthesis of Silver Nanoparticles Using Chenopodium ambrosioides. Journal of Nanomaterials. 2014. P. 951746. DOI: http://dx.doi.org/10.1155/2014/951746.

Biosynthesis of silver nanoparticles (AgNPs) was achieved using extract of Chenopodium ambrosioides as a reducer and coating agent at room temperature (25 degrees C). Two molar solutions of AgNO3 (1mM and 10mM) and five extract volumes (0.5, 1, 2, 3, and 5 mL) were used to assess quantity, shape, and size of the particles. The UV-Vis spectra gave surface plasmon resonance at 434-436 nm of the NPs synthesized with AgNO3 10mM and all extract volumes tested, showing a direct relationship between extract volumes and quantity of particles formed. In contrast, the concentration of silver ions was related negatively to particle size. The smallest (4.9 +/- 3.4 nm) particles were obtained with 1mL of extract in AgNO3 10mM and the larger amount of particles were obtained with 2mL and 5mL of extract. TEM study indicated that the particles were polycrystalline and randomly oriented with a silver structure face centered cubic (fcc) and fourier transform infrared spectroscopy (FTIR) indicated that disappearance of the -OH group band after bioreduction evidences its role in reducing silver ions.

CASTILLO-REYES, Francisco, SANCHEZ CHAPARRO, Juan David, RANGEL ESTRADA, Sandra Eloisa and KU, Jaime Canul, 2014, EFFECT OF MICROORGANISMS IN PROMOTING GERMINATION OF SEEDS FROM THE CACTUS Echinocactus platyacanthus LINK & OTTO. Interciencia. December 2014. Vol. 39, no. 12, p. 863–867.

In recent years numerous studies have been carried out to incorporate plant growth promoter micro-organisms in agricultural production. However, there is little information about studies on the effects of these micro-organisms on forest species, especially of arid zones. The present work is focused on evaluating the effect of inoculation of Bacillus spp., Trichoderma spp., Glomus intraradices and halophyte rhizobacteria on the germination of seeds of Echinocactus platyacanthus, a species native to Mexican semi-desert areas. Results show that microorganisms play an important role in promoting the germination process of Echinocactus seeds, the germination promotion by micro-organisms being higher when the seeds are washed.

EHSAN, M., LARA VIVEROS, F. M., HERNANDEZ, V. E., BARAKAT, M. A., ORTEGA, A. R., MAZA, A. V. and MONTER, J. V., 2015, Zinc and cadmium accumulation by Lupinus uncinatus Schldl. grown in nutrient solution. International Journal of Environmental Science and Technology. January 2015. Vol. 12, no. 1, p. 307–316. DOI: http://dx.doi.org/10.1007/s13762-013-0456-0.

The effects of zinc and cadmium on the growth, mineral composition (P, K, Ca, Mg, Fe, Zn, Mn, and Cu), and metal accumulation by lupine (bluebonnet, Lupinus uncinatus Schldl.) were investigated in a hydroponics experiment. Plants were exposed to increasing concentrations of Zn (0, 30, 40, and 50 mu M) and Cd (0, 3, 4, and 5 mu M) for 1 week. The species showed different patterns of metal accumulation and distribution in the plant parts, suggesting different mechanisms of metal tolerance for each metal. At the highest doses of Zn and Cd, the amounts of metals accumulated in roots, stems, and leaves were 1,289, 1,918, and 1,132 mg kg(-1) dry matter and 2,467, 227, and 164 mg kg(-1) dry matter, respectively. The shoot:root Zn ratios obtained for 50, 40, and 30 mu M treatments were 2.36:1, 2.28:1, and 2.32:1, respectively, whereas the ratio in case of Cd remained < 1 for the three Cd treatments. No significant effect on plant dry biomass was observed in either of the cases. Significant changes in plant mineral composition occurred, however, concentrations were generally above the deficiency levels. This suggests that this species may tolerate Cd without its hyperaccumulation and shows exclusion mechanism of Cd tolerance.

GARCIA-GOMEZI, Veronica, RAMIREZ-HERRERA, Carlos, FLORES-LOPEZ, Celestino and LOPEZ-UPTON, Javier, 2014, GENETIC DIVERSITY AND GENETIC STRUCTURE IN Pinus johannis. Agrociencia. December 2014. Vol. 48, no. 8, p. 863–873.

Pinus johannis M.-F. Robert-Passini is an endemic pinion nut pine of Mexico that grows in small populations. The objective of this study was to estimate the level of genetic diversity and degree of differentiation among populations in the natural distribution of P johannis. Mature strobili were collected from 130 tree of four populations. The genotype of each tree was determined in a sample of six megagametophytes, and nine enzyme systems with 16 loci were analyzed. In the four populations the number of alleles varied from 31 to 35. The average number of alleles per locus was 2.1, and the average percentage of polymorphic loci was 88 %. Average heterozygosity was 0.231, and expected average heterozygosity was 0.245. A deficit of heterozygous individuals (F-IS = 0.116 and F-IT = 0.176) was found in the four populations together and in each of them. The genetic differentiation among populations was moderate (F-ST = 0.062). Genetic diversity of P johannis was high with a moderate level of differentiation among populations.

GARCIA-JUAREZ, Guillermina, RAMIREZ-BRIBIESCA, J E., HERNANDEZ-VAZQUEZ, Maricela, HERNANDEZ-CALVA, Luz M., DIAZ-APARICIO, Efren and OROZCO-BOLANOS, Hermila, 2014, Risk analysis of brucelosis in the state of Tlaxcala. Salud Publica De Mexico. August 2014. Vol. 56, no. 4, p. 355–362.

Objective.To identify the risk of brucellosis in the state of Tlaxcala, Mexico. Materials and methods.A diagnosis of social type was conducted in the municipalities of Huamantla, Ixtenco and Teacalco, located in the eastern region of the state.The seroprevalence of brucellosis in goats and humans was determined. Results. 46.9% of producers know the programs of vaccination against brucellosis; 19.7% apply the vaccine and 80.3% do not apply the vaccine. Huamantla had the highest seroprevalence of animal brucellosis in 66.8%; San Jose Teacalco distributes unpasteurized cheeses to a distance of 270 km, increasing the risk of infection with brucellosis. Ixtenco recorded the highest prevalence of brucellosis in humans, with 1.51%.Conclusion.The municipalities studied present risks of infection and spread of brucellosis.

GARCIA-OLIVA, Felipe, COVALEDA, Sara, GALLARDO, Juan F., PRAT, Christian, VELAZQUEZ-DURAN, Rodrigo and ETCHEVERS, Jorge D., 2014, Firewood extraction affects carbon pools and nutrients in remnant fragments of temperate forests at the Mexican Transvolcanic Belt. Bosque. 2014. Vol. 35, no. 3, p. 311–324. DOI: http://dx.doi.org/10.4067/S0717-92002014000300006.

Globally, remnant fragments of forests represent the main carbon reservoir of terrestrial ecosystems, but they suffer strong degradation due to uncontrolled wood extraction mainly by tree cut for household fuel use and charcoal production. The present study evaluates the degradation caused by wood extraction on carbon pools and soil nutrient dynamics in temperate forests distributed in remnant fragments located in central Mexico. Four sites with different intensity of wood extraction were chosen for measuring carbon pools and nutrient fluxes during two years. Both, aboveground carbon biomass and soil organic carbon values decreased with the intensity of forest degradation. The degraded forest (DF) showed total carbon content 55 % lower than that shown by the seminatural forest (SF). Additionally, litterfall production was reduced in DF as compared to SF; the decomposition rate of standing litter was higher in the latter site. As a consequence, DF had lower organic matter inputs to the soil than that presented by SF. Soil extractable ammonium and microbial biomass-carbon and -nitrogen were lower in DF than in SF. It was concluded that the uncontrolled wood extraction in these remnants of temperate forest in Mexico significantly reduced the carbon pools, carbon and nutrient fluxes through litterfall and consequently, the soil nutrient dynamics were disrupted.

GONZALEZ GARDUNO, Roberto, MENDOZA DE GIVES, Pedro and TORRES HERNANDEZ, Glafiro, 2014, Variability in the Infection of F1 Katahdin x Pelibuey Crossbred Lambs to Gastrointestinal Parasitic Nematodes in a Warm Humid Climate. Acta Scientiae Veterinariae. 12 December 2014. Vol. 42.

Background: In sheep production systems based on grazing, gastrointestinal nematodes (GIN) are one of the main problems faced by farmers. The occurrence of anthelmintic resistance in GIN has endangered the productive activity of sheep, so that one alternative has been through the selection of sheep. The selection programs are based on evaluation of parasitism by measuring the fecal egg counts (FEC) of GIN due to the high correlation between the FEC and worm burdens. The identification of resistant and susceptible lambs requires knowing the FEC after the infection. The aim of this research was to determine the intra-breed variability on FEC of GIN in Katahdin x Pelibuey grazing sheep. Materials, Methods & Results: The experiment was conducted in Tabasco, Mexico in a warm humid climate. The study was carried out in three stages: in stage I, the FEC was recorded in newly weaned lambs experimental infected with 1600 infective larvae (L 3) of Haemonchus contortus and Cooperia curticei (85% and 15% respectively). Twenty lambs were drenched with albendazole and 20 more lambs were considered as control without any anthelmintic treatment. In stage II acquired resistance was determined in the same animal group after a break period following the same treatments. In stage III new lambs were introduced to paddocks and the FEC was recorded in their first infection. Every 15 days fecal sample, live weight and blood samples were taken to determine FEC, daily gain weight and packed cell volume. Data were analyzed with a model of repeated measures over time. In order to establish the level of anti-parasitic resistance in the lambs, a categorization of the lambs according to their FEC was performed based on the EPG mean and standard deviation. Subsequently another statistical analysis was performed by category to determine the EPG, PCV and DWG values per group. In primary infection, both lambs treated with albendazole and control group reached a maximum elimination at 32 days post-infection (4202 +/- 558 EPG mean). In the second natural infection the same lambs had less FEC (989 +/- 378 EPG), while in the newly weaned lambs of the third stage the FEC was rapidly increasing at 18 days (2950 +/- 471). Derived from the categorization process of the lambs, it was observed that resistance animals had lower FEC (282 +/- 197.5) and higher PCV (27.9 +/- 2.5 %) than the susceptible animals (5424 +/- 3790 FEC and 25.19 +/- 1.95 %, respectively). However, weight gains were similar among the groups (0.04 +/- 0.05 kg) and packed cell volume was similar between resistant and intermediate group. A negative correlation (r = -0.30) was obtained between PCV and FEC due to H. contortus population was abundant. Discussion: During the pre-patent period, no paddock contamination occurred; so, no lamb re-infections were expected. This fact can explain why the subsequent reduction in the larvae population occurred after 35 days infection. A similar behavior in the FEC was observed in single infections in other studies. It is important to remark that in the second stage the same experimental flock after deworming with levamisole showed evidence of acquired resistance against GIN after being exposed for second time to the infection. In the third stage, the increasing in the FEC and reduction of the PCV values in the flock required an urgent anthelmintic treatment; because six animals had shown a PCV ranged between 17 and 19%; so it was decided to terminate the experiment. It is concluded a low percentage of lambs showed the characteristics of resistance during the first infection, selection of animals with resistance to gastrointestinal parasitic nematodes is possible and it should be investigated in depth in further studies as a possible potential tool of parasitic control.

GONZALEZ-PACHECO, B. E., ROJAS-MARTINEZ, R. I., OCHOA-MARTINEZ, D. L. and SILVA-ROSALES, L., 2014, First Report of a 16sr Iv Group Phytoplasma Associated with Lethal Yellowing in Agave Tequilana. Journal of Plant Pathology. 2014. Vol. 96, no. 3, p. 603–603.

GONZALEZ-SANTAROSA, Maria G, BAUTISTA-MARTINEZ, Nestor, ROMERO-NAPOLES, Jesus, REBOLLAR-ALVITER, Angel, CARRILLO-SANCHEZ, Jose L. and HERNANDEZ-FUENTES, Luis M., 2014, Population Fluctuation and Spatial Distribution of Trioza Aguacate (hemiptera: Triozidae) on Avocado (lauraceae) in Michoacan, Mexico. Florida Entomologist. December 2014. Vol. 97, no. 4, p. 1783–1793.

The psyllid Trioza aguacate Hollis & Martin (Hemiptera: Triozidae) causes deformation of leaves and young shoots of avocado. In recent years, population densities of this pest in avocado orchards have increased. The objectives of this study were to determine seasonal fluctuations of the populations of eggs, nymphs, and adults of T. aguacate, how these fluctuations are related to the incidence of avocado vegetative shoots, temperature and rainfall at 3 different altitudes in Michoacan, Mexico, i.e., 2,130 m, 1,860 m and 1,293 m. In addition, we attempted to determine the spatial distributions of nymphs and adults found on avocado vegetative shoots. We sampled the populations of adult and immature T. aguacate every 20 days from Jan 2012 to Jul 2013. To estimate population densities, 9 trees were selected in each orchard, and the trees were distributed in the form of a cross. From each replicate of trees, 4 shoots were randomly collected, and the eggs and nymphs were counted on them. Adults counts were obtained from yellow traps established at the 4 cardinal points in each tree. During the same period, young vegetative shoots, temperature and rainfall were recorded. The results showed that this psyllid was not present at all in the orchard located at the low altitude level of 1,293 m. The psyllid was present at the medium altitude site from Jan to Jun, and from Dec to Jun at the high altitude site. All of the development stages were most abundant from Mar to May, when avocado vegetative shoots were most abundant in both years. The abundance of eggs and nymphs showed a positive relationship with young vegetative shoots, a negative relationship with rainfall, and the eggs showed a positive relationship with temperature. The incidence of adults was strongly related with spring budding, but not significantly correlated with temperature. Both nymphs and adults had an aggregated spatial distribution.

HERNANDEZ, P. A., MENDOZA, G. D., BARCENA, R., MONTES, M. C. and MARTINEZ, J. A., 2014, Effect of a Xylanolytic Enzymatic Extract from Cellulomonas flavigena on In Situ Ruminal Digestion of Agricultural Wastes. Animal Nutrition and Feed Technology. September 2014. Vol. 14, no. 3, p. 481–488. DOI: http://dx.doi.org/10.5958/0974-181X.2014.01350.X.

In situ ruminal digestibility of four low quality forages (corn stover, sugarcane bagasse, wheat straw and alfalfa hay control) was evaluated with the addition of enzymatic extract of Cellulomonas flavigena. The enzyme extract (42 IU xylanases ml(-1)) was sprinkled over the forages at 1 ml g(-1) 24h before incubation. Samples were incubated in the rumen of a Holstein cow fitted with a ruminal cannula for 3, 6, 9, 12, 24, 48 and 72h. There were positive effects of the enzyme (P<0.05) on forage DM digestibility at 24 and 48 h of incubation. However, there was no variation in the NDF digestion owing to enzyme or the forage source. In contrast, ADF degradation showed differences (P<0.05) among forages in all incubation times, indicating that the enzyme acted on the hemicellulose and fodder containing different cell wall percentages. Results indicate that Cellulomonas flavigena enzymatic extract improves in situ degradation of DM and ADF in low quality forages

INTERIAN-KU, Victor M., VAQUERA-HUERTA, Humberto, VALDEZ-HERNANDEZ, Juan I., GARCIA-MOYA, Edmundo, ROMERO-MANZANARES, Angelica and BORJA-DE LA ROSE, Amparo, 2014, Influence of Morphological and Environmental Factors on Diameter Growth. Revista Chapingo Serie Ciencias Forestales Y Del Ambiente. December 2014. Vol. 20, no. 3, p. 255–270. DOI: http://dx.doi.org/10.5154/r.rchscfa.2013.05.018.

Caesalpinia gaumeri Greenm is an important timber species in the tropical deciduous forest in southeast Mexico. The trunks of this species are used as posts in rural construction. In this study we investigated which morphological and environmental factors influence annual diameter growth, in order to establish the best turnover period. Diameter growth in 32 trees located in four diameter categories were evaluated and classified according to quality and sunlight incidence on the crowns of the trees. The study lasted 22 months and the diameter at breast height was measured and recorded bi-monthly. The results indicate that Average Growth Rate (AGR) increased from the smallest to the largest diameter categories, from the damaged to the healthy crown qualities and from intermediate to total incidences of sunlight. Highest AGR was observed in diameter categories of 12.50 to 22.49 cm in trees with symmetrical crown quality and the crown under full sunlight. The cumulative AGR was highly significant (P < 0.001) and positively correlated (r = 0.94) with the precipitation. Good growth in diameter for C. gaumeri requires a combination of bigger stem diameter, healthy and symmetric crown, full incidence of sunlight on the crown and a rainy season.

LI, You, WANG, Zhiliang, GUO, Jianjun, NAPOLES, Jesus Romero, JI, Yingchao, JIANG, Chunyan and ZHANG, Runzhi, 2014, Contribution to the knowledge of seed-beetles (Coleoptera, Chrysomelidae, Bruchinae) in Xinjiang, China. Zookeys. 2014. No. 466, p. 13–28. DOI: http://dx.doi.org/10.3897/zookeys.466.7283.

Nineteen species of seed-beetles belonging to the subfamily Bruchinae (Coleoptera, Chrysomelidae) were collected in Xinjiang, China. Of these, the following four were new records for China: Bruchus affinis Frolich, 1799, B. atomarius L., 1761, B. loti Paykull, 1800 and Kytorhinus kergoati Delobel & Legalov, 2009. We provide an annotated checklist, illustrations and a key to the 19 species.

LIRA-VARGAS, Alma A., CORRALES-GARCIA, J. Joel E., VALLE-GUADARRAMA, Salvador, PENA-VALDIVIA, Cecilia B. and TREJO-MARQUEZ, Maria A., 2014, Biopolymeric films based on cactus (Opuntia ficus-indica) mucilage incorporated with gelatin and beeswax. Journal of the Professional Association for Cactus Development. 2014. Vol. 16, p. 51–70.

Mucilage from stems of cactus (Opuntia ficus-indica) “Milpa Alta” (Mm) and “Toluca” (Mt), in a single ingredient condition and in mixture with gelatin and beeswax, was used to prepare biopolymeric films, which were assessed in terms of microscopic morphology, thickness, transparency, tensile strength, and permeability to water vapor, O-2, and CO2. Films based on Mm were thinner, with higher transparency, and higher tensile strength than those of Mt, but they had similar barrier properties to water vapor, O-2, and CO2. The addition of gelatin did not affect thickness and transparency of such films, but caused modification of the microscopic morphology, the mechanical strength, and the barrier properties to gases and water vapor. Furthermore, the addition of beeswax promoted the formation of aggregates in the microscopic morphology of films and these acquired smaller thickness, higher tensile strength, and higher barrier properties to O-2, CO2, and water vapor, which may give them better potential to be used in the postharvest conservation area of horticultural products, although they were less transparent.

LOPEZ-MARTINEZ, N., BIESAGA, M. and ZAVALETA-MEJIA, E., 2014, Modifications in the Phenylpropanoid Metabolism in Chilli Pepper Infected by Nacobbus Aberrans. Journal of Nematology. June 2014. Vol. 46, no. 2, p. 196–196.

MENDOZA CARINO, Mayra, QUEVEDO NOLASCO, Abel, BRAVO VINAJA, Angel, FLORES MAGDALENO, Hector, DE LA ISLA DE BAUER, Maria de Lourdes, GAVI REYES, Francisco and ZAMORA MORALES, Bertha Patricia, 2014, Ecological status of rivers and riparian vegetation within the new General Mexican Water’s Law context. Revista Internacional De Contaminacion Ambiental. November 2014. Vol. 30, no. 4, p. 429–436.

Rivers are vital units in the functioning of the watersheds that, due to the transportation and circulation of water, allow the existence of life. They are of great ecological and environmental value because of their influence on other ecosystems as well as the benefits they give to humankind, not only in the consumption for irrigation but also in the use in the agricultural and industrial areas. However, almost all the rivers in Mexico show a certain type of deterioration. About 70 % of the aquatic systems shows contamination which diminishes the health of these ecosystems. The objective of this work is to propose that the riparian vegetation should be included in the making of the new general law of water because its influence on the maintenance and rehabilitation of the ecological state of rivers is fundamental. It has been suggested a new law that contains a section of environmental protection which includes the riparian vegetation as a key element to protect, preserve, and restore rivers. Likewise, the boundaries of this vegetation should be according to the natural conditions of flooding in the bed of the river, with a once-in-every eight years-frequency, according to the variability of flow. In addition, its handling must consider the reforestation and maintenance of native vegetation species in each region.

MONTES-HERNANDEZ, Luis A., ARAHON HERNANDEZ-GUZMAN, J., LOPEZ-SANCHEZ, Higinio, SANTACRUZ-VARELA, Amalio, VAQUERA-HUERTA, Humberto and VALDIVIA-BERNAL, Roberto, 2014, In situ PHENOTYPIC EXPRESSION OF AGRONOMIC AND MORPHOLOGICAL TRAITS IN POPULATIONS OF THE JALA LANDRACE. Revista Fitotecnia Mexicana. December 2014. Vol. 37, no. 4, p. 363–371.

In situ conservation of genetic diversity in maize (Zea mays L.) has been made for years by traditional farmers, through planting native populations, as is the case of the Jala landrace, whose preservation is threatened by urban growth and natural factors. The distinctive characteristics of this landrace, such as plant height and ear length, have become dimibished. The number of farmers who grow in situ population of the Jala landrace is low, and seed of this landrace is often exchanged among them. For these reasons, it is relevant to assess whether or not there is phenotypic variation among current, conserved populations of the Jala landrace in Jala, Nayarit, Mexico, its place of origin and primary distribution. In situ morphological characterization of 18 Jala landrace populations and seven controls were evaluated in 2010 using a 5 x 5 Lattice design with two replications, at three environments within the Jala Valley. With the averages of variables through environments, a combined analysis of variance, Tukey’s mean comparison, principal component analysis (PCA) and cluster analysis (ADC) were performed. PCA defined that the most influential variables for explaining the observed variation were ear length, plant height and cob height. ACD defined three groups of populations, in which there was greater phenotypic similarity with most of the current populations. It is concluded that in the Jala maize landrace there is low phenotypic variation among current in situ conserved populations, with a presumably reduced and common genetic base.

MUNIZ-MERINO, Manolo, CIBRIAN-TOVAR, Juan, HIDALGO-MORENO, Claudia, BAUTISTA-MARTINEZ, Nestor, VAQUERA-HUERTA, Humberto and ALDAMA-AGUILERA, Cristobal, 2014, VOLATILE COMPOUNDS ATTRACT THE PEPPER (Capsicum spp.) WEEVIL (Anthonomus eugenii Cano) AND SYNERGIZE ITS AGGREGATION PHEROMONE. Agrociencia. December 2014. Vol. 48, no. 8, p. 819–832.

The pepper (Capsicum spp.) weevil (Anthonomus eugenii Cano) is the principal pepper pest in America, and its management requires efficient monitoring techniques. The host volatile compounds could be used for this purpose. In this research the attraction of A. eugenii adults towards an individual compound and 12 mixtures of synthetic volatile compounds (identified previously in Capsicum spp.) was evaluated, the effect of three isomers [(Z)-beta-ocimene, (E)-beta-ocimene, and D-limonene] was determined in the weevil response, and the best mixture of host volatiles was evaluated, as well as their combination with the A. eugenii aggregation pheromone and the pheromone alone. The insect’s response was evaluated through pairwise choice experiments, carried out in a Y-type olfactometer, with two treatments. The proportions of insects respondig to each treatment were compared with the binomial test. Results showed that the mixture of (Z)-beta-ocimene, D-limonene and 2-isobutyl-3-methoxypyrazine attracted (p <= 0.01) A. eugenii adults of both sexes. The (Z)-3-hexenyl acetate and the terpinolene, added individually to the prior combination, increased the response of females (p <= 0.05) and males (p <= 0.01), respectively. The inclusion of (E)-beta-ocimene as principal compound, in the same mixture, increased the response by males (p <= 0.05) and the exclusion of D-limonene did not decrease the effectiveness of the remaining combination. In the final experiments, males had a greater response to the mixture of host volatile compounds (p <= 0.05) and to its combination with the A. eugenii aggregation pheromone (p <= 0.01) than to the pheromone by itself; in contrast, females did not show a differentiation in their choice. The research allowed selecting pepper volatile compounds with potential to attract A. eugenii adults.

MUNOZ-RUIZ, Miguel A., VALDEZ-LAZALDE, Jose R., DE LOS SANTOS-POSADAS, Hector M., ANGELES-PEREZ, Gregorio and MONTERROSO-RIVAS, Alejandro I., 2014, Inventory and Mapping of Temperate Forest in Hidalgo, Mexico Through Spot and Field Data. Agrociencia. December 2014. Vol. 48, no. 8, p. 847–862.

Remote sensors combined with geospatial analytical methods provide important tools for measuring forest biophysical variables at a lower cost and at broader spatial and temporal scales than traditional forest inventories. The objective of this study was to analyze the relationship between data of the National Inventory of Forest and Soils (INFyS) of Mexico and spectral data from images of the SPOT platform for spatial estimation of basal area, timber volume and overlapping tree cover in the temperate and mesophyll forests of Hidalgo, Mexico. Four approaches to the analysis were used to generate models that describe the inventory and the distribution of the variables of interest: 1) multiple linear regression, 2) K-nearest neighbor (K-nn), 3) ratio and regression estimators, and 4) traditional forest inventory. The estimations derived from the first three methods are within the confidence interval of 95 % of the traditional forest inventory, and the values derived from ratio and regression estimators produced narrower confidence intervals. The analysis of the results indicate significant correlation between the INFyS data and the spectral bands of the SPOT satellite, particularly with the green, near infrared and mid infrared bands, as well as with the indexes and simple ratios based on these bands.

ORTIZ-CEBALLOS, Angel I., AGUIRRE-RIVERA, Juan R., SALGADO-GARCIA, Sergio and ORTIZ-CEBALLOS, Gustavo, 2015, Maize-Velvet Bean Rotation in Summer and Winter Milpas: A Greener Technology. Agronomy Journal. February 2015. Vol. 107, no. 1, p. 330–336. DOI: http://dx.doi.org/10.2131/agronj14.0276.

In Central America, the traditional cropping system milpa de alio (summer season) and tornamilpa (winter season) were compared over 3 yr (2007-2009). Our experimental objectives were to measure the performance fa maize (Zea mays L.) velvet bean [Mucuna pruriens (L.) DC. subsp. utilis (Wight) Burck] mid milpa system throughout the summer and winter cultivation, to detect any problems associated with velvet bean use, and to determine the contribution of this tropical legume to soil fertility and maize productivity. In each crop season (separated in space and time) we used a completely randomized design with a 2 x 2 factorial arrangement of treatments with five repetitions each: without velvet bean and without fertilizer ( V F), with velvet bean and without fertilizer (+V-F), without velvet bean and with fertilizer (-V+F), and with velvet bean and with fertilizer (+V+F). Results showed that in the winter milpas the presence of velvet bean significantly increased the soil pH, organic matter content, total N, and decreased soil bulk density. In both cycles (winter and summer), treatment with velvet bean (+V) produced higher grain yield, while the treatment without velvet bean (-V) had a lower production. We concluded that the use of velvet bean in the winter milpa contributed to the restoration of soil fertility and increased yield maize in agricultural systems of the small-holder farmers based on low external input.

PERALTA-ANTONIO, N., REBOLLEDO-MARTINEZ, A., BECERRIL-ROMAN, A. E., JAEN-CONTRERAS, D. and DEL ANGEL-PEREZ, A. L., 2014, Response to organic fertilization in mango cultivars: Manila, Tommy Atkins and Ataulfo. Journal of Soil Science and Plant Nutrition. 2014. Vol. 14, no. 3, p. 688–700.

The objective was evaluating the response to mineral (230-0-300 and 230-0-0 g NPK tree(-1)) and organic: vermicompost, bokashi and chicken manure (5 and 10 t ha(-1)) fertilizers in soil nutrimental content (pH, MO, macro and micronutriments), trunk diameter, flowering, and yield of three mango cultivars: “Manila”, “Tommy Atkins”, and “Ataulfo”. For soil variables were design completely random and other variables a split-plot in completely random. Differences between contents of N, K, Ca, Cu and Zn were showed in soil. Differences were showed between cultivars in trunk diameter. Flowering showed differences among cultivars and fertilizers. Regarding yield in 2010, only “Tommy Atkins” fruits were harvested, showing differences between fertilizers and control. In 2011, were differences among cultivars and fertilizers, chicken manure and mineral fertilizers outperformed the control. In 2012, “Tommy Atkins” outperformed “Ataulfo”. It is concluded that chicken manure 10 t ha(-1), were similar to nitrogen doses on soil contents of N, K, Cu and Zn; fertilizer do not have influence in the trunk diameter; on flowering and yield, bokashi and chicken manure 10 t ha(-1), were similar to nitrogen doses.

PINTO RUIZ, Rene, ORTEGA REYES, Luis, GOMEZ CASTRO, Heriberto, GUEVARA HERNANDEZ, Francisco and HERNANDEZ SANCHEZ, David, 2014, Animal behavior and diet chracteristics of cattle grazing on stargrass in monoculture and associated with trees. Revista Mexicana De Ciencias Pecuarias. September 2014. Vol. 5, no. 3, p. 365–374.

The objective of this study was to evaluate, animal behavior, quality, and composition of the diet selected by cattle grazing on stargrass (Cynodon plectostachyus) in monoculture and associated with Leucaena leucocephala (Lam.) De Wit. and Guazuma ulmifolia (Lam.) in the dry tropics of Chiapas, Mexico. For this purpose, animals’ behavior was observed for 24 h. It was estimated quality as well as botanical composition of the diet selected. Data wereanalyzed by variance with a completely random design. Comparison of means was carried out using Tukey’s test. Non significant differences were reported for the animal behavior data (P>0.05). In the associated grassland, it was found that more time was dedicated to browsing during the dry season (P<0.05). The best diet selected, in terms of crude protein was found in the associated grassland (P<0.001), for both seasons. In this grassland, woody plants were found in the diet selected during both seasons. Nevertheless, more woody species contributed to the diet during the dry as compared to the rainy season (52.1 versus 26.9 %, respectively).

REVERCHON, Frederique, DEL PILAR ORTEGA-LARROCEA, Maria and PEREZ-MORENO, Jesus, 2015, Structure and diversity of ectomycorrhizal resistant propagules in Pinus montezumae neotropical forests and implications for seedling establishment. Mycoscience. March 2015. Vol. 56, no. 2, p. 214–223. DOI: http://dx.doi.org/10.1016/j.myc.2014.06.005.

Ectomycorrhizal (ECM) fungal communities have been relatively poorly documented in neotropical forests. We analyzed the structure and diversity of the ECM resistant propagules present in the soil of Mexican neotropical forests dominated by Pinus montezumae. Soil samples were collected under mature P. montezumae, and microcosms were set up with bioassayed seedlings. The ECM propagules were formed by relatively few taxa that were evenly distributed across the sampled area. Some taxa, such as Rhizopogon spp. and Atheliaceae sp., formed an extensive mycelial system, which is likely to confer them with an advantage for seedling colonization. We also compared the species composition of the ECM propagules with the ECM communities previously assessed on the roots of seedlings and adult trees. They were represented by different taxa, although similarity analyses did not detect differences in species occurrence. Only two taxa, belonging to the Atheliaceae family, were shared between field and bioassayed seedlings, whereas 12 taxa were common to field seedlings and adult trees. The lower similarity between bioassayed and field seedlings suggests that fungal taxa found as resistant propagules are not active in mycelial networks in field conditions and that mycorrhizal network-mediated colonization may be prevalent in this neotropical forest. (C) 2014 The Mycological Society of Japan. Published by Elsevier B.V. All rights reserved.

ROCANDIO-RODRIGUEZ, Mario, SANTACRUZ-VARELA, Amalio, CORDOVA-TELLEZ, Leobigildo, LOPEZ-SANCHEZ, Higinio, CASTILLO-GONZALEZ, Fernando, LOBATO-ORTIZ, Ricardo, GARCIA-ZAVALA, J. Jesus and ORTEGA-PACZKA, Rafael, 2014, Morphological and Agronomic Characterization of Seven Maize Races from the Highlands of Mexico. Revista Fitotecnia Mexicana. December 2014. Vol. 37, no. 4, p. 351–361.

Within the diversity of maize (Zea mays L.) in Mexico, one of the most interesting genetic groups is the Mexican Pyramidal Complex grown in the Central highlands of the country. This study assessed the morphological and agronomic diversity in a large sample of populations of the seven races of maize most commonly cultivated in the highlands of Central Mexico (Arrocillo Amarillo, Chalqueno, Conic, Elotes Conicos, Cacahuacintle, Palomero Toluqueno and Purepecha), and to register information of characteristics that describe the prevailing variation of the races under study. Field experiments were established during the 2010 Spring-Summer agricultural season with 119 representative accessions of the aforementioned races of maize, at Ciudad Serdan and San Mateo Capultitlan, Puebla, and at Montecillo, State of Mexico, using an 11 x 11 simple lattice experimental design. Thirty-two quantitative traits were recorded and submitted to analysis of variance, and 13 of those traits were selected based on their repeatability and correlation coefficients, for applying multivariate analyses. Analysis of variance showed highly significant differences among genotypes for all the analyzed traits. The dispersion of accessions ended up as a continuum distributed throughout the Cartesian plane formed by the first two principal components, mainly influenced by traits related to ear and kernel size (ear length, kernel width and thickness, and the ratio kernel width/kernel length), as well as days to female flowering and number of leaves above the ear. The traits less affected by the environment were the most appropriate ones for grouping the accessions. Results of this study confirmed the grouping of the accessions of previously described races, as well as the interrelations among them as reported in previous studies; however, our result are more precise than the former studies in defining the groups and the interrelationships among the races because of the large sample sizes used.

ROCANDIO-RODRIGUEZ, Mario, SANTACRUZ-VARELA, Amalio, CORDOVA-TELLEZ, Leobigildo, LOPEZ-SANCHEZ, Higinio, CASTILLO-GONZALEZ, Fernando, LOBATO-ORTIZ, Ricardo and JESUS GARCIA-ZAVALA, J., 2014, Detection of genetic diversity of seven maize races from the high central valleys of Mexico using microsatellites. Maydica. 2014. Vol. 59, no. 1-4, p. 146–153.

In Mexico there is a broad diversity of maize. To design schemes of genetic improvement and germplasm conservation, this diversity must first be assessed. In this context, an analysis of microsatellites was conducted to estimate the degree of variation and to analyze the structure and genetic diversity of seven maize (Zea mays L) landraces from the High Central Valleys of Mexico (Arrocillo Amarillo, Cacahuacintle, Chalquefio, Conico, Elotes Conicos, Palomero Toluquerio and Purepecha) as well as the teosinte races Chalco [Zea mays ssp. mexicana (Schrader) Iltis] and Balsas [Zea mays ssp. parviglumis (Iltis and Doebley)]. Seed from 107 accessions kept in Mexican germplasm banks was used. We analyzed 31 SSR loci to estimate genetic variation based on the number of alleles per locus, proportion of polymorphic loci and index of expected heterozygosity, and genetic structure using Wright F statistics. Races were grouped based on principal component and cluster analyses. A total of 636 alleles were identified, averaging 20.52 alleles per locus, 92.75% of which were polymorphic loci. Also found were 100 alleles exclusive of some of the studied populations. Occurrence of these alleles was low, representing 16% of the total alleles found. It was determined that 76.3% of the genetic diversity of the cultivated landraces of the High Valleys of Mexico resides within populations and the remaining 23.7% is between populations. Well-defined groups of the races Cacahuacintle and Purepecha, as well as two groups of the Chalqueno race, were observed. The Purepecha race formed a compact group separate from the rest, while a large sample of the Elotes Conicos race group was placed intermediately among one of the groups of the Chalqueno race.

ROY, A., STONE, A., OTERO-COLINA, G., SCHNEIDER, W. L., HARTUNG, J. S. and BRLANSKY, R. H., 2014, Genetic variability in the nucleocapsid genes of nuclear citrus leprosis virus reveals the presence of a distinct species of dichorhavirus. Phytopathology. November 2014. Vol. 104, no. 11, p. 101–101.

SALDANA Y HERNANDEZ, Maria Isabel, GOMEZ ALVAREZ, Regino, RIVERA CRUZ, Maria del Carmen, ALVAREZ SOLIS, Jose David, ORTIZ GARCIA, Carlos Fredy and PAT FERNANDEZ, Juan Manuel, 2014, Effect of Organic Fertilizers on Soil Microbial Dynamics and Production. Interciencia. November 2014. Vol. 39, no. 11, p. 809–815.

Organic fertilizers provide an important contribution of organic matter that modifies the physical, chemical and microbiological characteristics of the soil. To determine the impact of solid and liquid fertilizers on cultures of Alpinia purpurata, the supply of organic C, total N and available P of five organic fertilizers, the population density of phosphate solubilizing bacteria (PSB), the indigenous arbuscular mycorrhizal fungi (AMP), and the plant responses were evaluated, at 365 days, on a Fluvisol soil. The treatments were compost, vermicompost, fermented manure, Bokashi and liquid humus, at doses of 6Mg.ha(-1) of solid fertilizers, and 60 l.ha(-1) of liquid fertilizers, and compared with chemical fertilizer (150-50-250) and a control. The organic fertilizers applied showed that after a year, the C, N and P concentrations in the soil maintained acceptable nutritional levels for production. Organic fertilizers increased five times the population density of PSB and 12% the total colonization by AMF, promoting a higher P availability for the plants, improving the production of total biomass and flower quality, fermented manure and compost standing out in production.

SALINAS-RIOS, T., SANCHEZ-TORRES-ESQUEDA, M. T., HERNANDEZ-BAUTISTA, J., DIAZ-CRUZ, A., NAVA-CUELLAR, C., ORTEGA-CERRILLA, M. E., CORDERO-MORA, J. L., VAQUERA-HUERTA, H. and VELASCO, J. L. F., 2014, Carcass characteristics, physicochemical changes and oxidative stress indicators of meat from sheep fed diets with coffee pulp. Arquivo Brasileiro De Medicina Veterinaria E Zootecnia. December 2014. Vol. 66, no. 6, p. 1901–1908. DOI: http://dx.doi.org/10.1590/1678-7747.

The purpose of this study was to determine how feeding sheep coffee pulp affects carcass characteristics and what changes occur in physicochemical, antioxidant capacity and oxidation of the meat during refrigerated storage. The experiment was carried out in 15 Blackbelly lambs weighing an average 22.86 +/- 0.76kg. The animals were assigned to three treatments: T0=control diet, T1=diet with 8% coffee pulp, and T2=diet with 16% coffee pulp. After fattening for 56 days, the sheep were slaughtered and the carcasses assessed. The inclusion of 16% coffee pulp in the diet increased carcass dressing from 48.19 to 50.83% and decreased the amount of fat in rumen and intestines from 3.43 to 2.53% (P<0.05). The inclusion of coffee pulp in the diet did not alter the amount of crude protein or fat in meat or its oxidation and antioxidant capacity during refrigerated storage. However, the inclusion of coffee pulp in the diet decreased fat in the rumen and intestines, and thus increased the amount of usable meat.

SANCHEZ, Jaime, ESTRADA-CASTILLON, Eduardo, ARIAS, Salvador, MURO, Gisela, GARCIA-ARANDA, Mario and GARCIA-MORALES, Leccinum J., 2014, Diversity of Cacti in the Arid and Semi-Arid Zone of Durango, Mexico. Interciencia. November 2014. Vol. 39, no. 11, p. 794–802.

A list of the diversity of cacti in the arid and semi-arid zone of Durango, Mexico is presented The zone includes 16 municipalities that belong to the Region of Chihuahua Desert. Field trips were made for specimen collection and registration in each municipality. The best represented genera are Coryphantha, Opuntia, Echinocereus and Mammillaria. The globose and cylindrical growth forms are the most common ones in the region. The municipalities with highest diversity were Mapimi, Tlahualilo and Nazas, while those with the largest numbers of species at risk were PeliOn Blanco, Mapimi, Tlahualilo and Nazas.

SANCHEZ-LOPEZ, Ariadna S., GONZALEZ-CHAVEZ, Ma Del Carmen A., CARRILLO-GONZALEZ, Rogelio, VANGRONSVELD, Jaco and DIAZ-GARDUNO, Margarita, 2015, Wild Flora of Mine Tailings: Perspectives for Use in Phytoremediation of Potentially Toxic Elements in a Semi-Arid Region in Mexico. International Journal of Phytoremediation. 2015. Vol. 17, no. 5, p. 476–484. DOI: http://dx.doi.org/10.1080/15226514.2014.922922.

The aim of this research was to identify wild plant species applicable for remediation of mine tailings in arid soils. Plants growing on two mine tailings were identified and evaluated for their potential use in phytoremediation based on the concentration of potentially toxic elements (PTEs) in roots and shoots, bioconcentration (BCF) and translocation factors (TF). Total, water-soluble and DTPA-extractable concentrations of Pb, Cd, Zn, Cu, Co and Ni in rhizospheric and bulk soil were determined. Twelve species can grow on mine tailings, accumulate PTEs concentrations above the commonly accepted phytotoxicity levels, and are suitable for establishing a vegetation cover on barren mine tailings in the Zimapan region. Pteridium sp. is suitable for Zn and Cd phytostabilization. Aster gymnocephalus is a potential phytoextractor for Zn, Cd, Pb and Cu; Gnaphalium sp. for Cu and Crotalaria pumila for Zn. The species play different roles according to the specific conditions where they are growing at one site behaving as a PTEs accumulator and at another as a stabilizer. For this reason and due to the lack of a unified approach for calculation and interpretation of bioaccumulation factors, only considering BCF and TF may be not practical in all cases.

SANCHEZ-MERAZ, J. A., GONZALEZ-MUNOZ, S. S., PINOS-RODRIGUEZ, J. M., LOPEZ-HERNANDEZ, Y. and MIRANDA, L. A., 2014, Effects of Slow-Release Urea on in Vitro Degradation of Forages. Journal of Animal and Plant Sciences. December 2014. Vol. 24, no. 6, p. 1840–1843.

The objective of this study was to evaluate the in vitro effects of slow release urea on gas production and degradation of dry matter and neutral detergent fiber for alfalfa hay, oat straw and corn silage and Stover. The addition of the slow release urea in alfalfa and oat cultures did not improve the degradation of these substrates. However in forages with low content of crude protein, e.g. corn silage and stover, the addition of slow-release urea alone or in combination with urea resulted in a significant increase in degradation and gas production.

SANTIAGO-SANTIAGO, V., TOVAR-PEDRAZA, J. M., AYALA-ESCOBAR, V. and ALANIS-MARTINEZ, E. I., 2014, Occurrence of Powdery Mildew Caused by Podosphaera Clandestina on Black Cherry in Mexico. Journal of Plant Pathology. July 2014. Vol. 96, no. 2, p. 438–438.

SAYNES, Vinisa, DELGADO, Jorge A., TEBBE, Caleb, ETCHEVERS, Jorge D., LAPIDUS, Daniel and OTERO-ARNAIZ, Adriana, 2014, Use of the new Nitrogen Index tier zero to assess the effects of nitrogen fertilizer on N2O emissions from cropping Systems in Mexico. Ecological Engineering. December 2014. Vol. 73, p. 778–785. DOI: http://dx.doi.org/10.1016/j.ecoleng.2014.09.063.

Mexico is one of the largest users of N fertilizer in the world, and the 2nd largest user in Latin America after Brazil. Across large areas of Mexico, N fertilizers are being over-applied, resulting in lower N use efficiency. Mexico’s greenhouse gas (GHG) inventory (in CO2 equivalents) reports that agricultural production contributes to about 12% of the country’s emissions, with N2O-N emissions from fertilizer contributing about half of the GHG emissions from agriculture. Mexico does not have tools that can be used to assess N fertilizer use and emissions of N2O-N from organic and inorganic sources. Such tools could be used to help nutrient managers implement management practices that increase N use efficiencies and reduce N2O-N emissions. The new Nitrogen Index tier zero tool was used to assess N use efficiencies and N2O-N emissions in different cropping systems of Mexico. Mexico’s current GHG inventory for agriculture just multiplies the use of N fertilizer in the country by 1% to assess national emissions of N2O. When we tested the new tier zero Nitrogen Index, it performed much better than the current methodology for calculating Mexico’s N2O emissions, and N2O emissions predicted by the tool were correlated with observed values (P < 0.01). The N index tool was closer to measured values than the current method used for Mexico’s GHG inventory. We propose that this prototype of the Nitrogen Index tier zero for Mexico can be used to assess the effects of cropping systems and N management practices on emissions of N2O-N in Mexico to improve the accuracy of the national inventory of N2O-N emissions in Mexico, which is reported to the United Nations Framework Convention on Climate Change (UNFCCC). Additionally, the tool can also be used to assess N management practices to increase N use efficiency with just a minimal amount of information provided by the user. Published by Elsevier B.V.

VAZQUEZ-ALONSO, Mariana T., BYE, Robert, LOPEZ-MATA, Lauro, PULIDO-SALAS, Ma Teresa P., MCCLUNG DE TAPIA, Emily and KOCH, Stephen D., 2014, Ethnobotany of the Teotihuacan culture. Botanical Sciences. December 2014. Vol. 92, no. 4, p. 563–574.

The purpose of the research reported here was to develop a list of plants utilized by the ancient inhabitants of prehispanic Teotihuacan through the botanical and ethnobotanical interpretation of archaeobotanical and iconographic records. The resulting register of useful plants is comprised of 77 taxa, based on published studies and archaeological reports. A Cultural Significance Index was proposed in order to combine the information from different sources and evaluate their relative importance. Identified archaeobotanical remains and their interpretation based on archaeological excavations provide direct evidence for the use of plants. Representations in ceramics and mural paintings, along with evidence associated with cultivation or importation of some species, provide indirect evidence. Maize (Zea mays L.) is characterized as the most significant cultural species. The uses attributed to taxa reported from the archaeological record and related species were then consulted in the Florentine Codex, as well as contemporary ethnobotanical studies, both of which offer many additional references to the ways in which these plants were employed. Medicinal uses appear to be the least important at Teotihuacan (eight taxa); however, according to more recent sources, 57% of the species could have had medicinal applications. A total of 125 potentially useful plants were identified from Teotihuacan, based on the ethnobotanical interpretation, and includes 17 species definitely grown in Teotihuacan and 108 additional exploited taxa associated with different types of vegetation. Twenty-eight plants were domesticated in Mexico. This study contributes to an understanding of the relationship between the inhabitants of Teotihuacan to their local and regional flora.

VILLASENOR, Jose A. and GONZALEZ-ESTRADA, Elizabeth, 2015, A variance ratio test of fit for Gamma distributions. Statistics & Probability Letters. January 2015. Vol. 96, p. 281–286. DOI: http://dx.doi.org/10.1016/j.spl.2014.10.001.

New estimators for the parameters of the Gamma distribution are proposed, which are used for constructing a test a fit for this model based on the ratio of two variance estimators. The asymptotic null distribution of the test statistic is also included. (C) 2014 Elsevier B.V. All rights reserved.

 

Parte II. Documentos Indizados en SCOPUS durante enero y febrero de 2015

AGUAS-ATLAHUA, A., GARCÍA-PÉREZ, E., RUIZ-ROSADO, O. and TRINIDAD-SANTOS, A., 2014, Fruit quality of lychee (litchi chinensis sonn.) produced in veracruz state, México. Revista Fitotecnia Mexicana. 2014. Vol. 37, no. 4, p. 373–380.

Lychee (Litchi chinensis Sonn.) is a fruit originating from China and Vietnam which is cultivated in México also, and Veracruz is cultivated with “Mauritius” and “Brewster” cultivars and it is the main state for the national and international markets. The aim of this research was to evaluate the physical and chemical characteristics of lychee fruits produced in six orchards located at the central and northern regions of the state of Veracruz. For this study 4 kg were sampled per each orchard, from which 40 fruits were randomly selected for quality evaluation. The variables measured were: length, diameter, firmness, weight of fruit and its components (e.g. pulp, peel and seed), total soluble solids, titratable acidity, and pericarp color. The “Mauritius” fruits varied in quality amongst orchards. The Lechuguillas orchard showed the biggest fruits with 35.1 mm length, 21.2 g of total weight and 16.8 g of pulp weight. Furthermore, fruits of this site had low acidity, acceptable peel color and high content of total soluble solids.

AGUIÑIGA-SÁNCHEZ, I., SOTO-HERNÁNDEZ, M., CADENA-IÑIGUEZ, J., RUÍZ-POSADAS, L.D.M., CADENA-ZAMUDIO, J.D., GONZÁLEZ-UGARTE, A.K., WEISS STEIDER, B. and SANTIAGO-OSORIO, E., 2015, Fruit Extract from A Sechium edule Hybrid Induce Apoptosis in Leukaemic Cell Lines but not in Normal Cells. Nutrition and Cancer. 2015. Vol. Article in Press. DOI: http://dx.doi.org/10.1080/01635581.2015.989370.

The antiproliferative potential of a crude extract from the chayote hybrid H-837-07-GISeM® and its potential for apoptosis induction were assessed in leukaemic cell lines and normal mouse bone marrow mononuclear cells (BM-MNCs). The extract strongly inhibited the proliferation of the P388, J774, and WEHI-3 cell lines (with an IC50 below 1.3 μg·mL−1), reduced cell viability, and induced apoptotic body production, phosphatidylserine translocation, and DNA fragmentation. However, the extract had no effect on BM-MNCs. We postulate that these properties make the extract a good candidate for an anti-tumour agent for clinical use.

ÁLVAREZ-CASTRO, N.V., CORRALES-GARCIA, J., HERNANDEZ-MONTES, A., DEL ROSARIO GARCIA-MATEOS, M., PEÑA-VALDIVIA, C.B. and QUIROZ-GONZALEZ, B., 2014, Development of a snack from xoconostle (Opuntia matudae Scheinvar) sweetened with neotame and its antioxidant capacity. Journal of the Professional Association for Cactus Development. 2014. Vol. 16, p. 15–31.

The xoconostle (Opuntia matudae Scheinvar) is a sour fruit, of which the peel is consumed. It is perishable, but it has a beneficial effect on human health, as recognized popularly in Mexico. The objective of this study was to create a snack of dried xoconostle using neotame, an artificial non-caloric sweetener, to improve flavor. We present (a) a partial chemical characterization of the fruit (total phenolic content (TP) and antioxidant activity (AA)), (b) dehydration techniques (heating by convection and freeze-drying), and (c) sensorial characterization of the final product. The experimental unit was 40 g of fresh xoconostle peel with three replications. The sweetener did not affect dehydration time of convective heat. The sweetened lyophilized xoconostle had lower TP and AA than unsweetened xoconostle. The sensorial analysis showed that lyophilized xoconostle sweetened with neotame (aqueous solution 32 mg L-1) has acceptable flavor and appearance.

ARAQUE-PADILLA, R.A., MONTERO-SIMÓ, M.J., RIVERA-TORRES, P. and ARAGÓN-GUTIÉRREZ, C., 2014, Moderating the Relationship Between Price and Perceived Value of Ethical Products. Journal of Agricultural and Environmental Ethics. 2014. Vol. Article in Press. DOI: http://dx.doi.org/10.1007/s10806-014-9528-5.

Interest in ethical aspects associated to product acquisition and consumption is a growing trend among consumers. In this context, the concept of “product with ethical attributes” has arisen to refer to products with explicit social and environmental characteristics. However, one of the factors that most hinders the purchasing of these products is certainly price. Given the difficulty of reducing price, the question that arises is the extent to which other product attributes can attenuate the negative impact of price on perceived value. We assume that the special benefits associated to this type of products (ethics, quality and health) are, at a different level, attenuators of the relationship between price and perceived value. Focusing on Fair Trade organic coffee, hypotheses are tested regarding survey data from 407 customers. They were interviewed in an actual purchasing scenario. The models are tested using conventional Structural Equation Models and the Latent Moderated Structural Equation method. The results obtained shed some light on a highly generalised belief that the marketing of these products can only be improved by reducing their price. However, although a price reduction could be desirable, albeit complicated in this product category, its effects could be reduced by acting on other variables such as the ethical aspects, quality and healthiness of this product category.

BARRALES-LÓPEZ, A., ROBLEDO-PAZ, A., TREJO, C., ESPITIA-RANGEL, E. and RODRÍGUEZ-DE LA O, J.L., 2015, Improved in vitro rooting and acclimatization of Capsicum chinense Jacq. plantlets. In Vitro Cellular and Developmental Biology - Plant. 2015. Vol. Article in Press. DOI: http://dx.doi.org/10.1007/s11627-015-9671-3.

In vitro conditions such as low light intensity, the levels of sucrose and other nutrients, and high relative humidity may cause anatomical and physiological changes that have negative effects on acclimatization of regenerated plants. The management of these conditions during in vitro culture could improve the plant ex vitro performance. The influences of light intensity, sucrose concentration, the nutritional composition of the culture medium, and culture container size on in vitro rooting and acclimatization were evaluated in Capsicum chinense cv. Naranja plants. The size of the culture container vessel did not affect plant growth. The best responses of the growth variables tested (plant height, number of leaves, number of roots, dry weight, and osmotic potential) and of survival and rooting were obtained with a photosynthetic photon flux density (PPFD) of 28 μmol m−2 s−1 and H medium with sucrose supplementation at either 1.5% or 3% (w/v). The combination of a PPFD of 28 μmol m−2 s−1 and H medium with 1.5% sucrose can be used for successful rooting of C. chinense adventitious shoots, to enhance the performance of the plantlets in the greenhouse or field and to reduce production costs. The factors studied during in vitro culture significantly influenced ex vitro growth.

BERGER, S., PÉREZ-RODRÍGUEZ, P., VETURI, Y., SIMIANER, H. and DE LOS CAMPOS, G., 2015, Effectiveness of shrinkage and variable selection methods for the prediction of complex human traits using data from distantly related individuals. Annals of Human Genetics. 2015. Vol. 79, no. 2, p. 122–135. DOI: http://dx.doi.org/10.1111/ahg.12099.

Genome-wide association studies (GWAS) have detected large numbers of variants associated with complex human traits and diseases. However, the proportion of variance explained by GWAS-significant single nucleotide polymorphisms has been usually small. This brought interest in the use of whole-genome regression (WGR) methods. However, there has been limited research on the factors that affect prediction accuracy (PA) of WGRs when applied to human data of distantly related individuals. Here, we examine, using real human genotypes and simulated phenotypes, how trait complexity, marker-quantitative trait loci (QTL) linkage disequilibrium (LD), and the model used affect the performance of WGRs. Our results indicated that the estimated rate of missing heritability is dependent on the extent of marker-QTL LD. However, this parameter was not greatly affected by trait complexity. Regarding PA our results indicated that: (a) under perfect marker-QTL LD WGR can achieve moderately high prediction accuracy, and with simple genetic architectures variable selection methods outperform shrinkage procedures and (b) under imperfect marker-QTL LD, variable selection methods can achieved reasonably good PA with simple or moderately complex genetic architectures; however, the PA of these methods deteriorated as trait complexity increases and with highly complex traits variable selection and shrinkage methods both performed poorly. This was confirmed with an analysis of human height.

CARRASCO-HERNÁNDEZ, V., PÉREZ-MORENO, J., QUINTERO-LIZAOLA, R., ESPINOSA-SOLARES, T., LORENZANA-FERNÁNDEZ, A. and HERNÁNDEZ, V.E., 2015, Edible species of the fungal genus hebeloma and two neotropical pines. Pakistan Journal of Botany. 2015. Vol. 47, no. 1, p. 319–326.

Mexico has one of the largest diversities of pines and ectomycorrhizal fungi known world-wide. Therefore, describing native ectomycorrizal species from the country associated with pines is important because of their biotechnological potential in the forestry and food sectors. Worldwide, Hebeloma has generally been considered a genus of poisonous ectomycorrhizal fungi. However, interestingly, in central Mexico there is a complex of under-studied Hebeloma species which are used as food in large quantities and have a great economic and social importance. Three edible species of Hebeloma widely marketed in the country were identified: Hebeloma alpinum, H. mesophaeum and H. leucosarx with scanning electron microscopy on the basis of different ornamentation patterns in the spores of these species. Synthesis was carried out by inoculating two Neotropical pines with sporomes of the three described Hebeloma species. To achieve this, inoculated pines were kept in greenhouse conditions during one year. A characteristic morphotype for each fungal species was observed and it is described here. The first known description of the morphotype of Hebeloma alpinum with pines is presented. This seminal work gives a tool to identify the morphotypes produced by the main edible ectomycorrhizal species of Hebeloma marketed in Mexico, with biotechnological potential to inoculate pines used in reforestation programmes in Neotropical areas.

CASTAÑEDA-SAUCEDO, M.C., VALDÉS-MIRAMONTES, E.H., TAPIA-CAMPOS, E., DELGADO-ALVARADO, A., BERNARDINO-GARCÍA, A.C., RODRÍGUEZ-RAMÍREZ, M.R. and RAMIREZ-ANAYA, J.P., 2014, Effect of freeze-drying and production process on the chemical composition and fatty acids profile of avocado pulp. Revista Chilena de Nutricion. 2014. Vol. 41, no. 4, p. 404–411. DOI: http://dx.doi.org/10.4067/S0717-75182014000400009.

Freeze-drying technology is the best dehydration process to preserve shelf-life and allowing avocado to maintain its sensorial and nutritional characteristics. The aim of this work was to determine if the freeze-drying and production condition have an effect on the nutritional quality of the avocado pulp grown in rain-fed and irrigation orchards. Four treatments were applied: non-freezedried rain-fed fruits, non-freeze-dried irrigation fruits, freeze-dried rain-fed fruits and freeze-dried irrigation fruits. Results showed that the fruit is made up of 71.4%, 16%, and 12.6% pulp, seed and skin, respectively. The pulp is made up of 71.51%, 19.96%, 2.81%, 0.51% and 1.51% water, lipids, ashes, crude fiber and protein, respectively. Avocado oil is composed by 61%, 18.8%, 11.6% and 7% oleic, palmitic, linoleic, and palmitoleic fatty acids, respectively. The freeze-drying decreased the linoleic acid by 1.43 g/100g. Under rain-fed conditions 4% and 13% less total fat and oleic fatty acid are produced than in irrigation conditions. We conclude that freeze-dried avocado pulp shows slight changes in their nutritional quality.

CÁZARES-SÁNCHEZ, E., CHÁVEZ-SERVIA, J.L., SALINAS-MORENO, Y., CASTILLO-GONZÁLEZ, F. and RAMÍREZ-VALLEJO, P., 2015, Grain composition variation among native maize (Zea mays L.) of Yucatan, Mexico. Agrociencia. 2015. Vol. 49, no. 1, p. 15–30.

The diversity of races and native populations of maize (Zea mays L.) has great food, social and economic importance for rural communities in Mexico, and should to be studied for documentation, conservation and utilization. The aim of this study was to evaluate the variation in protein, lysine, tryptophan, crude fiber, ash, oil and starch of grain in a collection of 41 native populations of maize from the north-central region of Yucatan, Mexico, of the populations known locally as Nal t’eel, Xmejen nal, T’síit bakal and Xnuuk nal. The materials were increased in Iguala, Guerrero, in the autumn-winter 2002-2003 cycles. The experimental design was randomized block with two replications per treatment; an ANOVA was carried out and treatments means were compared with Tukey’s test. There were significant differences (p≤0.05) in protein content (9.35 to 12.50 %), lysine (0.27 to 0.39 %), tryptophan (0.08 to 0.13 %), ash (1.12 to 1.83 %), oil (3.37 to 4.52 %), crude fiber (0.72 to 1.65 %) and starch (57.54 to 69.92 %). Besides, the variation patterns are associated with populations: early Nal t’eel and Xmejen nal had the highest contents of protein and tryptophan and late T’síit bakal and Xnuuk nal had lower contents of protein and higher contents of lysine. Six populations of Xmejen nal, one of Xnuuk nal and one of Nal t’eel were outstanding. Also, positive and significant correlation (p?0.05) was observed between ash and lysine (0.99) and tryptophan (0.97) content in the Nal t’eel group. The results showed high variability in grain composition, useful for breeding programs of native maize materials and to formulate strategies of in situ conservation of local collections in the study region.

CONTRERAS-GALLEGOS, E., DOMÍNGUEZ-PACHECO, F.A., HERNÁNDEZ-AGUILAR, C., CARBALLO-CARBALLO, A., CRUZ-OREA, A., THOEN, J. and GLORIEUX, C., 2014, Study of Thermal and Structural Properties of Starch Granules from Different Maize Genotypes. Food Biophysics. 2014. Vol. 10, no. 1, p. 19–24. DOI: http://dx.doi.org/10.1007/s11483-014-9344-5.

The thermal and structural properties of starch granules of four maize genotypes (Palomero Toluqueño native maize, HS-2 commercial hybrid, L3-Q2 M09 experimental hybrid and Cacahuacintle native maize) were studied. By using adiabatic scanning calorimetry (ASC), the specific heat capacity (cp(T)) of these samples was obtained. Also, by integration of the area under the cp(T) curves, the enthalpy for the starch gelatinization was determined, from which the percentage of gelatinized starch granules was obtained as a function of the temperature. From the X-ray diffraction patterns of the starch granules, the degree of crystallinity of the samples was derived. The average size of the starch granules, for the different maize genotypes, was calculated from the images obtained by Scanning Electron Microscopy (SEM). We found a correlation between the enthalpy of gelatinization and the average size of starch granules, and also between the degree of crystallinity and the average size of the starch granules.

DÍAZ-JOSÉ, J., DÍAZ-JOSÉ, O., MORA-FLORES, S., RENDÓN-MEDEL, R. and TELLEZ-DELGADO, R., 2014, Cacao in mexico: Restrictive factors and productivity levels. Chilean Journal of Agricultural Research. 2014. Vol. 74, no. 4, p. 397–403. DOI: http://dx.doi.org/10.4067/S0718-58392014000400004.

Cacao (Theobroma cacao L.) represents one of the most important agricultural crops of the humid Mexican tropics. In the last 10 yr, approximately 23.000 t of this grain were no longer produced per cycle. The objective of this study was to identify characteristics and factors that restrict production in the states of Tabasco and Chiapas. A survey was applied to obtain information about 184 producers and their plantations by two-stage sampling. Descriptive statistics were calculated and multilevel models were adjusted to analyze the information. Results show that there are differences (P &lt; 0.05) in cacao yield between municipalities (380 kg ha-1+ μojis the estimated residual for each municipality). Crop productivity levels are higher in the state of Tabasco than in Chiapas (644 and 344 kg ha-1, respectively). Incidence of frosty pod rot of cacoa, also known as moniliasis, induced by Moniliophthora roreri [(Cif) H.C. Evans, Stalpers, Samson &amp; Benny 1978] is significantly greater (P &lt; 0.05) in the state of Chiapas (60%) than in Tabasco (48%).Producers who carry out more crop management practices increase yields and decrease the pathogen’s impact on their plantations. Results suggest the need to apply differentiated public policies to promote production within each region or municipality.

DUARTE ZARAGOZA, V.M., GUTIÉRREZ CASTORENA, E.V., GUTIÉRREZ CASTORENA, M.C., CARRILLO GONZÁLEZ, R., ORTIZ SOLORIO, C.A. and TRINIDAD SANTOS, A., 2015, Heavy metals contamination in soils around tailing heaps with various degrees of weathering in Zimapán, Mexico. International Journal of Environmental Studies. 2015. Vol. 72, no. 1, p. 24–40. DOI: http://dx.doi.org/10.1080/00207233.2014.961310.

Dispersion of mine tailings is the main cause of heavy metal (HM) contamination in soils in Zimapán, Mexico; however, the extent of this problem has not been assessed. Therefore, the aims of this study were to determine the degree of contamination and to assess the influence of mine tailings with different degrees of weathering on the spatial distribution of HM in soils. Soil and mine tailing sampling was carried out. The HM concentration was determined by atomic absorption spectrophotometry; spatial analysis and the size of the contaminated areas were calculated using GIS software; the mine tailings were characterized physically, chemically and mineralogically. The results suggest that all the tailing heaps have contributed to the HM dispersion. High HM concentrations were founded in soils around mine tailings (9402 mg kg−1 Pb and 52 mg kg−1 Cd). Surface area contaminated with Pb and Cd was estimated at 6.2 and 2.7 km2, in urban soils, respectively.

DURÁN-GARCÍA, H.M., PÉREZ, A.L.P., LAUREL, H.O., ROSSEL, E.D., ESQUERRA, G.R., GALVAN, M.A. and RODRÍGUEZ-HERNÁNDEZ, J.L., 2015, Industrialization of runner bean (Phaseolus vulgaris L.). Journal of Food, Agriculture and Environment. 2015. Vol. 13, no. 1, p. 8–11.

The objective of this study was to set up optimal parameters for obtaining industrialized runner bean varieties and to choose those more suitable when obtaining dehydrated unbroken precooked bean. Taken into consideration rehydration time and physicochemical and sensorial attributes four varieties of runner bean, Bayo, Flor de mayo, Flor de junio and Negro, were utilized. In each one of them sorting, cleaning and wetting were carried out. After that, they were subjected to a precooking process and dehydration in a tray type dryer. For each variety and during each process temperature, water content, relative humidity and contents of ash, protein, carbohydrates and ethereal extract were determined and records were made of time taken for rehydration and boiling temperature and sensorial attributes like flavor, appearance, texture and aroma were obtained from hedonic acceptance tests. All four varieties of industrialized runner beans showed high content of ash, protein and carbohydrates. At the hedonic test, four varieties were qualified as “like slightly”, with no statistically differences between them. Analyzing texture and flavor, testers preferred Floor de mayo variety, according to appearance runner bean Bayo and regarding aroma runner bean Negro. Industrialization process allowed preserving organoleptic quality attributes from each variety as well as to maintain and increase their nutritional quality.

GARCÍA-OLIVA, F., COVALEDA, S., GALLARDO, J.F., PRAT, C., VELÁZQUEZ-DURÁN, R. and ETCHEVERS, J.D., 2014, Firewood extraction affects carbon pools and nutrients in remnant fragments of temperate forests at the Mexican Transvolcanic Belt. Bosque. 2014. Vol. 35, no. 3, p. 311–324. DOI: http://dx.doi.org/10.4067/S0717-92002014000300006.

Globally, remnant fragments of forests represent the main carbon reservoir of terrestrial ecosystems, but they suffer strong degradation due to uncontrolled wood extraction mainly by tree cut for household fuel use and charcoal production. The present study evaluates the degradation caused by wood extraction on carbon pools and soil nutrient dynamics in temperate forests distributed in remnant fragments located in central Mexico. Four sites with different intensity of wood extraction were chosen for measuring carbon pools and nutrient fuxes during two years. Both, aboveground carbon biomass and soil organic carbon values decreased with the intensity of forest degradation. The degraded forest (DF) showed total carbon content 55% lower than that shown by the seminatural forest (SF). Additionally, litterfall production was reduced in DF as compared to SF; the decomposition rate of standing litter was higher in the latter site. As a consequence, DF had lower organic matter inputs to the soil than that presented by SF. Soil extractable ammonium and microbial biomass- carbon and -nitrogen were lower in DF than in SF. It was concluded that the uncontrolled wood extraction in these remnants of temperate forest in Mexico signifcantly reduced the carbon pools, carbon and nutrient fuxes through litterfall and consequently, the soil nutrient dynamics were disrupted.

GONZÁLEZ-SANTAROSA, M.G., BAUTISTA-MARTÍNEZ, N., ROMERO-NÁPOLES, J., REBOLLAR-ALVITER, A., CARRILLO-SÁNCHEZ, J.L. and HERNÁNDEZ-FUENTES, L.M., 2014, Population fluctuation and spatial distribution of Trioza aguacate (Hemiptera: Triozidae) on avocado (Lauraceae) in Michoacan, Mexico. Florida Entomologist. 2014. Vol. 97, no. 4, p. 1783–1793. DOI: http://dx.doi.org/10.1653/024.097.0454.

The psyllid Trioza aguacate Hollis & Martin (Hemiptera: Triozidae) causes deformation of leaves and young shoots of avocado. In recent years, population densities of this pest in avocado orchards have increased. The objectives of this study were to determine seasonal fluctuations of the populations of eggs, nymphs, and adults of T. aguacate, how these fluctuations are related to the incidence of avocado vegetative shoots, temperature and rainfall at 3 different altitudes in Michoacan, Mexico, i.e., 2,130 m, 1,860 m and 1,293 m. In addition, we attempted to determine the spatial distributions of nymphs and adults found on avocado vegetative shoots. We sampled the populations of adult and immature T. aguacate every 20 days from Jan 2012 to Jul 2013. To estimate population densities, 9 trees were selected in each orchard, and the trees were distributed in the form of a cross. From each replicate of trees, 4 shoots were randomly collected, and the eggs and nymphs were counted on them. Adults counts were obtained from yellow traps established at the 4 cardinal points in each tree. During the same period, young vegetative shoots, temperature and rainfall were recorded. The results showed that this psyllid was not present at all in the orchard located at the low altitude level of 1,293 m. The psyllid was present at the medium altitude site from Jan to Jun, and from Dec to Jun at the high altitude site. All of the development stages were most abundant from Mar to May, when avocado vegetative shoots were most abundant in both years. The abundance of eggs and nymphs showed a positive relationship with young vegetative shoots, a negative relationship with rainfall, and the eggs showed a positive relationship with temperature. The incidence of adults was strongly related with spring budding, but not significantly correlated with temperature. Both nymphs and adults had an aggregated spatial distribution.

GUTIÉRREZ-CASTORENA, E.V., GUTIÉRREZ-CASTORENA, M.D.C. and ORTIZ-SOLORIO, C.A., 2015, Carbon capture and pedogenetic processes by change of moisture regime and conventional tillage in Aridisols. Soil and Tillage Research. 2015. Vol. 150, p. 114–123. DOI: http://dx.doi.org/10.1016/j.still.2015.02.001.

In recent years, conservation tillage has been promoted as a method of increasing the quality of agricultural soils; however, in the Aridisols of northeastern Mexico, this type of tillage is not practical because of the formation of natural crusts. Conventional tillage systems that include different culture practices have been used for six decades to increase the yields. However, little is known of the changes to the soil properties and modifications to the moisture control section. Six agricultural plots representative of 78,000 ha in districts of the state of Tamaulipas, Mexico were studied based on their management: rainfed or irrigated, with or without the incorporation of crop residues and with or without plot drainage. The results show that three moisture regimes occur in the soils according to the irrigation intensity and plot drainage: aridic, ustic and udic. The aridic regime presents the greatest organic carbon stock (58Mgha-1), stability of aggregates in particles &gt;2 mm in the arable layer and produces sorghum yields of up to 2.5tha-1. In the udic regime, because of plot drainage and the incorporation of crop residue and manure, there is high biological activity; in addition, stability of aggregates is along the whole profile, alkalinisation and redox processes occur, and short-cycle maize yields are up to 10tha-1. The different management practices for intense production modify the moisture regime but do not modify the organic carbon capture. The pedogenetic processes are related to the management intensity and cause the Aridisols to evolve into inceptisols in less than six decades of agricultural activity; however, only the redox processes are expressed in their classification despite a significant amount of calcitic features.

HERNÁNDEZ-GARCÍA, P.A., LARA-BUENO, A., MENDOZA-MARTÍNEZ, G.D., BÁRCENA-GAMA, J.R., PLATA-PÉREZ, F.X., LÓPEZ-ORDAZ, R. and MARTÍNEZ-GARCÍA, J.A., 2015, Effects of feeding yeast (Saccharomyces cerevisiae), organic selenium and chromium mixed on growth performance and carcass traits of hair lambs. Journal of Integrative Agriculture. 2015. Vol. 14, no. 3, p. 575–582. DOI: http://dx.doi.org/10.1016/S2095-3119(14)60833-9.

Yeasts and organic minerals are used in diets to improve health, productive performance and some carcass characteristics of ruminants and non-ruminants. Thirty-two lambs (Pelibuey×Katahdin; BW=(30.55±1.67) kg; n=8) were used in a 56-d feeding experiment to study the effects of different levels of live yeast (Saccharomyces cerevisiae; yeast), selenium (Se) and chromium (Cr) mixed (Se-Cr), and a mixture of yeast-Se-Cr on growth performance and carcass traits. Animals were stratified by body weight (BW) and randomly assigned to one of four treatments: 1) control group (0.0 g kg-1 yeast); 2) yeast (1.50 g kg-1 dry matter intake (DMI) d-1); 3) Se-Cr premix (1.5 mg kg-1 DMI d-1 for each mineral); and 4) yeast-Se-Cr mixture. There were no treatment effects on final BW; whereas lambs fed Se-Cr or yeast-Se-Cr had higher (P&lt;0.05) DMI than animals supplemented with only yeast. Average daily gain (ADG), gain:feed ratio, chop area, dorsal fat and carcass yield were similar (P&gt;0.05) among treatment groups. In conclusion, supplementation with yeast, Se-Cr mixed or yeast-Se-Cr did not improve ADG, final BW, back fat content and carcass yield of growing of Pelibuey×Katahdin lambs. Supplementation with Se-Cr and yeast-Se-Cr increased DMI, and approximately 250 g ADG animal-1 d-1 was produced with no negative effects on growth and health of the animals.

JIMENEZ-CASAS, M. and ZWIAZEK, J.J., 2014, Adventitious sprouting of Pinus leiophylla in response to salt stress. Annals of Forest Science. 2014. Vol. 71, no. 7, p. 811–819. DOI: http://dx.doi.org/10.1007/s13595-014-0379-z.

Context: Although adventitious shoots are produced in many tree species in response to injury, little is known about the effects of salinity on sprouting. Aims: The main objective was to examine the sprouting capacity of Pinus leiophylla seedlings in relation to injury and physiological changes induced by NaCl. Methods: Seedlings were grown in controlled-environment growth rooms and treated with 0, 100, 150, and 200 mM NaCl. Numbers of adventitious shoots were recorded and growth and physiological parameters measured after 64 days of treatments and following a 30-day recovery period. Results: NaCl treatments triggered sprouting of adventitious shoots, mainly in the lower parts of the stems. However, fewer sprouts were induced by 200 mM NaCl compared with the lower concentration treatments. These changes were accompanied by needle necrosis, decreased chlorophyll concentrations, seedling dry mass, and stem diameter. Stomatal conductance, net photosynthesis, and root hydraulic conductance decreased with increasing NaCl concentrations and did not return to the control levels after 30 days of stress relief. Conclusions: Pinus leiophylla has the regeneration potential when exposed to salinity. However, very high salt concentrations induce severe physiological impairments and, consequently, a decrease of this regeneration potential.

LIRA-VARGAS, A.A., LIRA-VARGAS, A.A., CORRALES-GARCIA, J.J.E., VALLE-GUADARRAMA, S., PEÑA-VALDIVIA, C.B. and TREJO-MARQUEZ, M.A., 2014, Biopolymeric films based on cactus (Opuntia ficus-indica) mucilage incorporated with gelatin and beeswax. Journal of the Professional Association for Cactus Development. 2014. Vol. 16, p. 51–70.

Mucilage from stems of cactus (Opuntia ficus-indica) “Milpa Alta” (Mm) and “Toluca” (Mt), in a single ingredient condition and in mixture with gelatin and beeswax, was used to prepare biopolymeric films, which were assessed in terms of microscopic morphology, thickness, transparency, tensile strength, and permeability to water vapor, O2, and CO2. Films based on Mm were thinner, with higher transparency, and higher tensile strength than those of Mt, but they had similar barrier properties to water vapor, O2, and CO2. The addition of gelatin did not affect thickness and transparency of such films, but caused modification of the microscopic morphology, the mechanical strength, and the barrier properties to gases and water vapor. Furthermore, the addition of beeswax promoted the formation of aggregates in the microscopic morphology of films and these acquired smaller thickness, higher tensile strength, and higher barrier properties to O2, CO2, and water vapor, which may give them better potential to be used in the postharvest conservation area of horticultural products, although they were less transparent.

LI, Y., WANG, Z., GUO, J., NÁPOLES, J.R., JI, Y., JIANG, C. and ZHANG, R., 2014, Contribution to the knowledge of seed-beetles (Coleoptera, Chrysomelidae, Bruchinae) in Xinjiang, China. ZooKeys. 2014. No. 466, p. 13–28. DOI: http://dx.doi.org/10.3897/zookeys.466.7283.

Nineteen species of seed-beetles belonging to the subfamily Bruchinae (Coleoptera, Chrysomelidae) were collected in Xinjiang, China. Of these, the following four were new records for China: Bruchus affinis Frolich, 1799, B. atomarius L., 1761, B. loti Paykull, 1800 and Kytorhinus kergoati Delobel & Legalov, 2009. We provide an annotated checklist, illustrations and a key to the 19 species.

LÓPEZ-PALACIOS, C., PEÑA-VALDIVIA, C.B., REYES-AGÜERO, J.A., AGUIRRE-RIVERA, J.R., RAMÍREZ-TOBÍAS, H.M., SOTO-HERNÁNDEZ, R.M. and JIMÉNEZ-BREMONT, J.F., 2015, Inter- and intra-specific variation in fruit biomass, number of seeds, and physical characteristics of seeds in Opuntia spp., Cactaceae. Genetic Resources and Crop Evolution. 2015. Vol. Article in Press. DOI: http://dx.doi.org/10.1007/s10722-015-0223-9.

Domestication is an evolutionary process that culminates with the origin of individuals or populations that are morpho-physiologically, chemically and genetically different from their wild, congeneric relatives. The aim of the present study was to quantify the inter- and intra-specific variation in fruit biomass, number of seeds, and physical characteristics of seeds in O. streptacantha Lem., O. hyptiacantha F.A.C. Weber, O. megacantha Salm-Dyck, O. albicarpa Scheinvar and O. ficus-indica (L.) Mill., the least, intermediate, and most highly domesticated species. The hypothesis was that selecting larger fruits with fewer and softer seeds (normal and aborted) during domestication reduced the interspecific variation in fruit biomass, number of seeds, and physical characteristics of seeds in Opuntia spp., Cactaceae. For fruits of 89 variants of the Southern Mexican Plateau, total biomass and biomass of pulp with seeds was quantified; seed length, width, thickness and dehydrated mass were measured, as well as hardness of normal seeds. The total number of seeds was quantified and normal and aborted seeds were counted separately. A randomized design, with 89 treatments (variants) and six replicates and a fruit as experimental unit per treatment was used. The data were analysed by ANOVA, Tukey’s multiple comparison test (p ≤ 0.05), multivariate ordination (principal components analysis) and classification (clustering analysis). Inter-specific analysis indicated that fruits of the most highly domesticated variants (O. albicarpa and O. ficus-indica) had higher biomass (p ≤ 0.05), followed by those of O. hyptiacantha and O. megacantha and wild variants of O. streptacantha, and non-significant differences existed in seed thickness or hardness. Fruit and pulp biomass were positively and significantly correlated with seed biomass. Species with greater domestication clustered according to their larger fruits (≥117.83 g) and the greater number of aborted seeds (≥65). Domestication of Opuntia has also modified seed dimensions and increased the number of aborted seeds per fruit (≤11 to ≥65).

MAKI-DÍAZ, G., PEÑA-VALDIVIA, C.B., GARCÍA-NAVA, R., ARÉVALO-GALARZA, M.L., CALDERÓN-ZAVALA, G. and ANAYA-ROSALES, S., 2015, Physical and chemical characteristics of cactus stems (Opuntia ficus-indica) for exportation and domestic markets. Agrociencia. 2015. Vol. 49, no. 1, p. 31–51.

Nopal (edible cactus stems, Opuntia spp.) is consumed and produced in México and the selection criteria for its export include only color, size and the absence of deformations seen by producers at the time of harvest. The objective of this study was to evaluate the physical and chemical characteristics of nopal for export and to contrast them with those of nopal for national consumption. The hypothesis was that the subjective selection of the two types of nopal by producers is related to physical characteristics and indirectly, to composition. The experimental design was completely random with factorial arrangement, with two factors and two levels (factor 1: destination, nopal for national consumption and for export; factor 2: groups of producers, Grupo PRONACUA and Grupo Agrícola Ixquitlán), and 50 repetitions (each one represented by one nopal). The study was performed in Otumba and San Martín de las Pirámides, Estado de México, México. The results were analyzed with ANOVA and Tukey’s multiple means comparison. The characteristics of the nopal samples evaluated were: weight, length, width, thickness, firmness and number of leaves, and content of moisture, mucilage, malic acid, chlorophyll and carotenoids. The presence of pesticides was also determined. Export nopales had significantly lower (p≤0.05) weight (38 g), length (2.2 cm), width (1 cm), apical thickness (0.8 cm), basal thickness (0.8 cm), moisture (0.3 %) and titratable acidity expressed as the malic acid content (0.2 %), and content of chlorophyll (0.46 mg 100 g-1) and carotenoids (0.1 mmol g-1) higher than those selected for national consumption; and both groups were free from the 20 most common pesticides used in vegetables. The physical characteristics and chemical composition of nopales for export are different than those destined for national consumption, and they could be used to complement the quality norms to help producers secure and increase the international market.

MONTES-HERNÁNDEZ, L.A., HERNÁNDEZ-GUZMÁN, J.A., LÓPEZ-SÁNCHEZ, H., SANTACRUZ-VARELA, A., VAQUERA-HUERTA, H. and VALDIVIA-BERNAL, R., 2014, In situ phenotypic expression of agronomic and morphological traits in populations of the Jala Landrace. Revista Fitotecnia Mexicana. 2014. Vol. 37, no. 4, p. 363–372.

In situ conservation of genetic diversity in maize (Zea mays L.) has been made for years by traditional farmers, through planting native populations, as is the case of the Jala landrace, whose preservation is threatened by urban growth and natural factors. The distinctive characteristics of this landrace, such as plant height and ear length, have become dimibished. The number of farmers who grow in situ population of the Jala landrace is low, and seed of this landrace is often exchanged among them. For these reasons, it is relevant to assess whether or not there is phenotypic variation among current, conserved populations of the Jala landrace in Jala, Nayarit, México, its place of origin and primary distribution. In situ morphological characterization of 18 Jala landrace populations and seven controls were evaluated in 2010 using a 5 x 5 Lattice design with two replications, at three environments within the Jala Valley. With the averages of variables through environments, a combined analysis of variance, Tukey’s mean comparison, principal component analysis (PCA) and cluster analysis (ADC) were performed. PCA defined that the most influential variables for explaining the observed variation were ear length, plant height and cob height. ACD defined three groups of populations, in which there was greater phenotypic similarity with most of the current populations. It is concluded that in the Jala maize landrace there is low phenotypic variation among current in situ conserved populations, with a presumably reduced and common genetic base.

ORTIZ-CEBALLOS, A.I., AGUIRRE-RIVERA, J.R., SALGADO-GARCIA, S. and ORTIZ-CEBALLOS, G., 2015, Maize-velvet bean rotation in summer and winter milpas: A greener technology. Agronomy Journal. 2015. Vol. 107, no. 1, p. 330–336. DOI: http://dx.doi.org/10.2134/agronj14.0276.

In Central America, the traditional cropping system milpa de año (summer season) and tornamilpa (winter season) were compared over 3 yr (2007-2009). Our experimental objectives were to measure the performance of a maize (Zea mays L.)-velvet bean [Mucuna pruriens (L.) DC. subsp. utilis (Wight) Burck] milpa system throughout the summer and winter cultivation, to detect any problems associated with velvet bean use, and to determine the contribution of this tropical legume to soil fertility and maize productivity. In each crop season (separated in space and time) we used a completely randomized design with a 2 × 2 factorial arrangement of treatments with five repetitions each: without velvet bean and without fertilizer (-V-F), with velvet bean and without fertilizer (+V-F), without velvet bean and with fertilizer (-V+F), and with velvet bean and with fertilizer (+V+F). Results showed that in the winter milpas the presence of velvet bean significantly increased the soil pH, organic matter content, total N, and decreased soil bulk density. In both cycles (winter and summer), treatment with velvet bean (+V) produced higher grain yield, while the treatment without velvet bean (-V) had a lower production. We concluded that the use of velvet bean in the winter milpa contributed to the restoration of soil fertility and increased yield maize in agricultural systems of the small-holder farmers based on low external input.

OSORIO, A.I., MENDOZA, G.D., PLATA, F.X., MARTÍNEZ, J.A., VARGAS, L. and ORTEGA, G.C., 2015, A simulation model to predict body weight gain in lambs fed high-grain diets. Small Ruminant Research. 2015. Vol. 123, no. 2-3, p. 246–250. DOI: http://dx.doi.org/10.1016/j.smallrumres.2014.12.004.

A simulation model was developed to predict the average daily gain (ADG) in lambs fed high-grain diets. The model is deterministic and is based on the energy intake estimated from the digestibility of the ration as well as based on the California Net Energy System. The model was evaluated using data from eight experiments (28 treatments), with diets containing 50-72% grain. The ADG estimated with the model (244 ± 44g/d) was similar to the observed ADG (249 ± 44g/d; t test, P=0.70). The model was described by the following equation: Y=40.96 + 0.85X (r2=0.74; P&lt;0.001), with an ADG residual value of -4.6 ± 23g. A statistical evaluation indicated a mean bias value of 4.6, a root mean square error of prediction of 23, and a concordance correlation coefficient of 0.86. The results indicate that the gain can be predicted in finishing lambs with an acceptable accuracy and precision according to the developed model, with an underestimation of 1.85%.

PICHARDO-GONZÁLEZ, J.M., AYALA-GARAY, Ó.J., GONZÁLEZ-HERNÁNDEZ, V.A. and FLORES-ORTIZ, C.M., 2014, Fatty acids and physiological quality of tomatillo (Physalis philadelphica lam.) Seed during natural ageing. Chilean Journal of Agricultural Research. 2014. Vol. 74, no. 4, p. 391–396. DOI: http://dx.doi.org/10.4067/S0718-58392014000400003.

In Mexico, 44 thousand hectares are planted with tomatillo or husk tomato (Physalis philadelphica Lam.), which occupies fourth place among the country’s vegetable species. However, research on this species is scarce, especially that related to the process of seed deterioration. We studied the effects of deterioration in tomatillo seed, var. CHF1-Chapingo, stored from 2-mo up to 7 yr with no climate control, 18.2 ± 5 °C and 41 ± 10% relative humidity, on physiological and biochemical variables during germination. It was found that germination, vigor, and respiratory activity decrease significantly from the first year of storage; thus, after 7 yr, germination and vigor decreased 99%, and respiratory activity of seed after 48 h imbibition decreased 78%. Linoleic acid (unsaturated) content correlated positively with germination (R = 0.78**) and with speed of radicle emergence (R = 0.79**). Germination correlated with speed of radicle emergence (R = 0.99**) and with respiratory activity after 48 h of imbibition (R = 0.79**). Both respiratory activity and fatty acid content are involved in natural deterioration of tomatillo seed.

REVERCHON, F., ORTEGA-LARROCEA, M.D.P. and PÉREZ-MORENO, J., 2015, Structure and diversity of ectomycorrhizal resistant propagules in Pinus montezumae neotropical forests and implications for seedling establishment. Mycoscience. 2015. Vol. 56, no. 2, p. 214–223. DOI: http://dx.doi.org/10.1016/j.myc.2014.06.005.

Ectomycorrhizal (ECM) fungal communities have been relatively poorly documented in neotropical forests. We analyzed the structure and diversity of the ECM resistant propagules present in the soil of Mexican neotropical forests dominated by Pinus montezumae. Soil samples were collected under mature P. montezumae, and microcosms were set up with bioassayed seedlings. The ECM propagules were formed by relatively few taxa that were evenly distributed across the sampled area. Some taxa, such as Rhizopogon spp. and Atheliaceae sp., formed an extensive mycelial system, which is likely to confer them with an advantage for seedling colonization. We also compared the species composition of the ECM propagules with the ECM communities previously assessed on the roots of seedlings and adult trees. They were represented by different taxa, although similarity analyses did not detect differences in species occurrence. Only two taxa, belonging to the Atheliaceae family, were shared between field and bioassayed seedlings, whereas 12 taxa were common to field seedlings and adult trees. The lower similarity between bioassayed and field seedlings suggests that fungal taxa found as resistant propagules are not active in mycelial networks in field conditions and that mycorrhizal network-mediated colonization may be prevalent in this neotropical forest.

ROCANDIO-RODRÍGUEZ, M., SANTACRUZ-VARELA, A., CÓRDOVA-TÉLLEZ, L., LÓPEZ-SÁNCHEZ, H., CASTILLO-GONZÁLEZ, F., LOBATO-ORTIZ, R., JESÚS GARCÍA-ZAVALA, J. and ORTEGA-PACZKA, R., 2014, Morphological and agronomic characterization of seven maize races from the highlands of México. Revista Fitotecnia Mexicana. 2014. Vol. 37, no. 4, p. 351–361.

Within the diversity of maize (Zea mays L.) in México, one of the most interesting genetic groups is the Mexican Pyramidal Complex grown in the Central highlands of the country. This study assessed the morphological and agronomic diversity in a large sample of populations of the seven races of maize most commonly cultivated in the highlands of Central México (Arrocillo Amarillo, Chalqueño, Cónico, Elotes Cónicos, Cacahuacintle, Palomero Toluqueño and Purépecha), and to register information of characteristics that describe the prevailing variation of the races under study. Field experiments were established during the 2010 Spring-Summer agricultural season with 119 representative accessions of the aforementioned races of maize, at Ciudad Serdán and San Mateo Capultitlán, Puebla, and at Montecillo, State of México, using an 11 × 11 simple lattice experimental design. Thirty-two quantitative traits were recorded and submitted to analysis of variance, and 13 of those traits were selected based on their repeatability and correlation coefficients, for applying multivariate analyses. Analysis of variance showed highly significant differences among genotypes for all the analyzed traits. The dispersion of accessions ended up as a continuum distributed throughout the Cartesian plane formed by the first two principal components, mainly influenced by traits related to ear and kernel size (ear length, kernel width and thickness, and the ratio kernel width/kernel length), as well as days to female flowering and number of leaves above the ear. The traits less affected by the environment were the most appropriate ones for grouping the accessions. Results of this study confirmed the grouping of the accessions of previously described races, as well as the interrelations among them as reported in previous studies; however, our result are more precise than the former studies in defining the groups and the interrelationships among the races because of the large sample sizes used.

RODRÍGUEZ-BLANCO, M.L., TABOADA-CASTRO, M.M., TABOADA-CASTRO, M.T. and OROPEZA-MOTA, J.L., 2015, Relating nitrogen export patterns from a mixed land use catchment in NW Spain with rainfall and streamflow. Hydrological Processes. 2015. Vol. Article in Press. DOI: http://dx.doi.org/10.1002/hyp.10388.

The temporal variability in nitrogen (N) transport in the Corbeira agroforestry catchment (NW Spain) was analysed from October 2004 to September 2008. Nitrate (NO3-N) and total Kjeldahl nitrogen (TKN) loads and concentrations were determined at various timescales (annual, seasonal and event). The results revealed a strong intra-annual and inter-annual variability in N transport influenced by weather patterns and consequently by the hydrological regime. Mean annual export of total N in the catchment was 5.5kgha-1year-1, with NO3-N being the dominant form. Runoff events comprised 10% of the study period but contributed 40 and 61% of the total NO3-N and TKN loads, respectively. The NO3-N and TKN concentrations were higher during runoff events than under baseflow conditions, pointing to diffuse sources of N. The mobilization of TKN during runoff events was attributed to surface runoff, while NO3-N might be related to subsurface and groundwater flow. Runoff events were characterized by high variability in N loads and concentrations. Higher variability was observed in N loads than in N concentrations, indicating that event magnitude plays an important role in N transport in this catchment; event magnitude explained approximately 96% of the NO3-N load. However, a combination of variables related to runoff event intensity (rainfall, discharge increase and kinetic energy) explained only 66% of the TKN load.

ROJAS, P., RODRÍGUEZ-LEYVA, E., REFUGIO LOMELI-FLORES, J. and LIU, T.-X., 2014, Biology and life history of Tamarixia triozae, a parasitoid of the potato psyllid Bactericera cockerelli. BioControl. 2014. Vol. 60, no. 1, p. 27–35. DOI: http://dx.doi.org/10.1007/s10526-014-9625-4.

Tamarixia triozae (Burks) (Hymenoptera: Eulophidae) is an important parasitoid of the potato psyllid, Bactericera cockerelli Sulc (Hemiptera: Triozidae). We quantified the biology and life table parameters of T. triozae parasitizing B. cockerelli nymphs under laboratory conditions (26 ± 2 °C, 60 ± 10 % RH and 14:10 [L:D] h). Parasitoid developmental times were 1.5, 3.5, 5.7 days for eggs, larvae and pupae respectively, with an average of 12.0 days from egg to adult emergence. Female pupae took 0.4 day longer to develop than male pupae. Adult females lived 19.9 ± 4.5 days and had a 1.9 ± 0.8 days preoviposition period. Each female laid an average of 165.4 ± 45.2 eggs during her lifetime. The net reproductive rate (R0), generation time (T), intrinsic rate of increase (rm), doubling time (DT) and the finite rate of increase (λ) were 130.9, 18.72, 0.26, 2.7, and 1.3 respectively. The potential for the use of T. triozae as a biological control agent of B. cockerelli is discussed.

SALINAS-RIOS, T., ORTEGA-CERRILLA, M.E., SÁNCHEZ-TORRES-ESQUEDA, M.T., HERNÁNDEZ-BAUTISTA, J., DÍAZ-CRUZ, A., FIGUEROA-VELASCO, J.L., GUINZBERG-PERRUSQUÍA, R. and CORDERO-MORA, J.L., 2015, Productive performance and oxidative status of sheep fed diets supplemented with coffee pulp. Small Ruminant Research. 2015. Vol. 123, no. 1, p. 17–21. DOI: http://dx.doi.org/10.1016/j.smallrumres.2014.09.008.

Productive performance, rumen fermentation and oxidative status of sheep fed diets supplemented with coffee pulp ensiled with 5% molasses were evaluated. Thirty-four Blackbelly cross-breed sheep, 6 months old, mean weight 21.2. ±. 0.63. kg, were assigned to three treatments T0: control treatment ( n= 11), T1: treatment with 8% coffee pulp in the diet ( n= 12), and T2: treatment with 16% coffee pulp in the diet ( n= 11). Coffee pulp at the levels evaluated did not affect daily weight gain, feed intake, and feed conversion ( P>. 0.05). However, water intake, acetic acid, butyric acid, and total volatile fatty acids significantly increased ( P<. 0.05) with the 16% coffee pulp diet. No differences ( P>. 0.05) were observed in the antioxidant capacity of the sheep’s plasma; however, lipid peroxidation was lower for sheep fed with 16% coffee pulp. The present study concluded that a supplemented sheep diet with coffee pulp up to 16% coffee pulp did not affect their productive parameters but reduced oxidative stress.

SALINAS-RIOS, T., SÁNCHEZ-TORRES-ESQUEDA, M.T., HERNÁNDEZ-BAUTISTA, J., DÍAZ-CRUZ, A., NAVA-CUELLAR, C., ORTEGA-CERRILLA, M.E., CORDERO-MORA, J.L., VAQUERA-HUERTA, H. and VELASCO, J.L.F., 2014, Carcass characteristics, physicochemical changes and oxidative stress indicators of meat from sheep fed diets with coffee pulp. Arquivo Brasileiro de Medicina Veterinaria e Zootecnia. 2014. Vol. 66, no. 6, p. 1901–1908. DOI: http://dx.doi.org/10.1590/1678-7747.

The purpose of this study was to determine how feeding sheep coffee pulp affects carcass characteristics and what changes occur in physicochemical, antioxidant capacity and oxidation of the meat during refrigerated storage. The experiment was carried out in 15 Blackbelly lambs weighing an average 22.86±0.76kg. The animals were assigned to three treatments: T0=control diet, T1=diet with 8% coffee pulp, and T2=diet with 16% coffee pulp. After fattening for 56 days, the sheep were slaughtered and the carcasses assessed. The inclusion of 16% coffee pulp in the diet increased carcass dressing from 48.19 to 50.83% and decreased the amount of fat in rumen and intestines from 3.43 to 2.53% (P<0.05). The inclusion of coffee pulp in the diet did not alter the amount of crude protein or fat in meat or its oxidation and antioxidant capacity during refrigerated storage. However, the inclusion of coffee pulp in the diet decreased fat in the rumen and intestines, and thus increased the amount of usable meat.

SOLANO, E., TERRAZAS, T. and GONZÁLEZ-BECERRIL, A., 2014, Comparative anatomy of the stem, leaf and inflorescence basal axis of Polianthes L. (Asparagaceae, Agavoideae) species. Feddes Repertorium. Vol. 124, no. 4, p. 105–115. DOI: http://dx.doi.org/10.1002/fedr.201300017.

The genus Polianthes belongs to Asparagaceae, subfamily Agavoideae (APG III, 2009) and is endemic to Mexico, spanning the states of Chihuahua and Tamaulipas in the north, and extending to the state of Oaxaca in the south. Its species are perennial, herbaceous plants with corms and bulbs. Their leaves are green or glaucous, linear or lanceolate. Inflorescences are in racemes or spikes with narrow and widely infundibuliform flowers, varying in color from white to red. The fruit is a capsule with black seeds. The number of species of Polianthes varies depending on the criteria to classify them. For example, in the first revision for the genus, Rose (1903) recognized 12 species. According to Espejo and López (1992), the genus has 15 species, whereas GarcíaMendoza and Galván (1995) reported 12 species, and Solano and Feria (2007) recognized 14 species and three varieties.

STAMATIU-SÁNCHEZ, K., ALARCÓN, A., FERRERA-CERRATO, R., NAVA-DÍAZ, C., SÁNCHEZ-ESCUDERO, J., CRUZ-SÁNCHEZ, J.S. and CASTILLO, M.P., 2014, Tolerance of filamentous fungi to endosulfan, chlorpyrifos and chlorothalonil in in vitro conditions. Revista Internacional de Contaminacion Ambiental. 2014. Vol. 31, no. 1, p. 23–37.

Endosulfan (EN), chlorpyrifos (CRP) and chlorothalonil (CTL) are carcinogenic and toxic pesticides in the environment, by which bioremediation efficient actions must be directed for detoxifying contaminated systems. Fungi such as Phanerochaete chrysosporium (PC), Trametes versicolor (TV) and some species of Trichoderma (TRI), Mucor, Fusarium and Penicillium are able to degrade pesticides. Seven fungal strains were isolated from agricultural soil, wheat straw, and wheat straw pieces. The seven fungal strains as well as three referential fungi (PC, TV and TRI) were cultivated by triplicate in Petri dishes with minimal mineral medium contaminated with increased doses of EN, CRP or CTL for 18 days. The mycelial growth (MG) and the percentage of growth inhibition (PGI) were determined. The three pesticides negatively affected the MG, but the fungal recovery was observed after 72 h for EN and CRP. At 18 days, strains K14S, PC, TV and TRI showed total recovery when exposed to EN. In contrast, all fungal strains showed a recovery to CRP at the 10th day. The MG for most fungal strains was significantly inhibited (P &lt; 0.0001) due to during CTL at 18 days. The fungicide CTL resulted in highest PGI, but strains K8S, K14S, K11TP, PC and TV were less affected. The fungal strains K12P, K8S, K14S, and K11TP showed acceptable tolerance to the three pesticides comparable to PC, TV and TRI. These four fungal strains are good candidates for being used for pesticide bioremediation.

TORRES, C., SILVA, G., TAPIA, M., RODRÍGUEZ, J.C., FIGUEROA, I., LAGUNES, A., SANTILLÁN, C., ROBLES, A., AGUILAR, S. and TUCUCH, I., 2014, Insecticidal activity of laurelia sempervirens (Ruiz & pav.) tul. essential oil against sitophilus zeamais motschulsky. Chilean Journal of Agricultural Research. 2014. Vol. 74, no. 4, p. 421–426. DOI: http://dx.doi.org/10.4067/S0718-58392014000400007.

The maize weevil Sitophilus zeamais Motschulsky is a worldwide key pest of stored products. Usually contact insecticides or fumigants are used against it, but problems as toxic residues, human intoxications, and resistance have triggered the search for alternative control methods as the use of essential oils. The objective of this research was to assess under laboratory conditions, the insecticidal properties of Laurelia sempervirens (Ruiz &amp; Pav.) Tul. essential oil against S. zeamais. In contact toxicity bioassay assessed treatments were 0 (control), 1.25, 2.5, 5.0, 10, 20, and 40 mL essential oil kg-1grain and 0 (control), 25, 50, 75, 100, 125, 150, and 175 μL essential oil L-1air in fumigant toxicity tests. The highest toxicity by contact activity was reached by concentrations higher than 10 mL essential oil kg-1grain (100% mortality). The same treatments totally inhibit F1. The dose of 175 μL essential oil L-1air showed a significant toxicity by fumigant activity causing 72.5% of dead insects. The other treatments did not surpass 5% mortality. In offspring effect (F1) bioassay, all treatments had an insect emergence significantly lower than the control but concentrations equal or higher than 10 mL essential oil kg-1grain prevented the emergence of F1during the 7 wk of bioassay. The residual effect of contact toxicity remained by 15 d. The treatments based on essential oil lead to a weight grain loss lower than control and germination was not affected. All assessed treatments showed repellent effect. The essential oil of L. sempervirens has promissory perspectives to maize weevil control.

TORRES, C., SILVA, G., TAPIA, M., RODRÍGUEZ, J.C., URBINA, A., FIGUEROA, I., LAGUNES, A., SANTILLÁN-ORTEGA, C., ROBLES-BERMÚDEZ, A. and AGUILAR-MEDEL, S., 2015, Insecticidal properties of Laurelia sempervirens powder to sitophilus zeamais Motschulsky (Coleoptera: Curculionidae) control. Boletin Latinoamericano y del Caribe de Plantas Medicinales y Aromaticas. 2015. Vol. 14, no. 1, p. 48–59.

Sitophilus zeamais is a key pest of stored cereals. The insecticidal properties of Laurelia sempervirens powder against S. zeamais were assessed in laboratory. The variable evaluated were mortality of adult insects by contact and fumigant toxicity, mortality of immature insects by contact toxicity, residual effect of powder stored under environmental or refrigerated conditions, adult insect emergence (F1), repellency and weight reduction and germination of maize. The concentrations evaluated were 0, 0.25, 0.5, 1.0, 2.0 and 4.0% and the experimental design was completely randomly. In contact toxicity bioassay all treatments showed mortality over 90% while fumigant activity did not exceed 40%. The F1 only was registered in treatment of 0.25% and control showing all other treatments 0%. In immature control bioassay all treatments exhibited statistical differences with control. The storage of powder under refrigerated conditions not improved the residual effect. All concentrations of powder assessed showed repellence. Germination and grain weight loss of maize seeds not showed significant differences with control. We concluded that L. sempervirens has promissory perspectives to stored grain pests control.

VILLALOBOS, E.B., LÓPEZ, M.Á.L., ALCALÁ, V.M.C., ALDRETE, A. and SUÁREZ, J.J., 2014, Cultural practices in the nursery that affect seedling quality of Enterolobium cyclocarpum. Bosque. 2014. Vol. 35, no. 3, p. 301–309. DOI: http://dx.doi.org/10.4067/S0717-92002014000300005.

Because one of the main problems that Enterolobium cyclocarpum faces in the planting site is the presence of weeds, to grow plants presenting appropriate characteristics that enable them to overcome these adverse conditions during reforestation appears as necessary. Therefore, after evaluating the responses of various morphological and physiological indicators, and a quality test experiment, the effects of three top pruning intensities (no pruning, 25% and 50% pruning) and three fertilization regimes (traditional, exponential and conventional) were studied during nursery production. This approach was made based on the fact that top pruning and fertilization in the nursery are cultural practices that improve seedling quality as long as the pruning intensity and fertilization regime are appropriate. There was no synergy between the two practices; however, each factor infuenced independently on the indicators evaluated. Top pruning at 25% and 50% did not improve the characteristics of E. cyclocarpum. However, the nutrient supply in a conventional way had a favorable effect when compared with other fertilization regimes. The results provided by the quality test established that conventional fertilization allows plants to perform satisfactorily when nutrient availability is limited.

VILLAR-LUNA, E., ROJAS-MARTÍNEZ, R.I., REYES-TREJO, B., ROCHA-SOSA, M. and ZAVALETA-MEJÍA, E., 2015, Expression of hydroxymethylglutaryl-CoA reductase 2 (HMG2) gene in chilli (Capsicum annuum L.) CM334 infected by nacobbus aberrans and phytophthora capsici. Agrociencia. 2015. Vol. 49, no. 1, p. 69–75.

Plants of chilli Capsicum annuum L. CM334 show a high level of resistance to Phytophthora capsici, but are susceptible to Nacobbus aberrans; such resistance has been associated with capsidiol accumulation, a sesquiterpene phytoalexin. In the present study the expression of hydroxymethylglutaryl-CoA reductase 2 gene (HMG2, associated with sesquiterpene phytoalexins biosynthesis) in CM334 chilli roots inoculated with N. aberrans and in combination with P. capsici, was determined by qRT-PCR. The levels of HMG2 transcripts were significantly reduced (p≤0.05) from -1.57 to -1.28-fold in the interaction CM334/N. aberrans; whereas in roots inoculated only with the oomycete, the accumulation of transcripts occurred earlier and at higher levels (1.52 to 3.54-fold). In plants inoculated with both pathogens, the expression was higher compared with those inoculated with the nematode only (p≤0.05), but generally lower than the expression observed in roots of plants inoculated with the oomycete alone. The expression of the HMG2 gene associated with defense was reduced in CM334 chilli plants infected by N. aberrans.

ZHANG, X., PÉREZ-RODRÍGUEZ, P., SEMAGN, K., BEYENE, Y., BABU, R., LÓPEZ-CRUZ, M.A., SAN VICENTE, F., OLSEN, M., BUCKLER, E., JANNINK, J.-L., PRASANNA, B.M. and CROSSA, J., 2015, Genomic prediction in biparental tropical maize populations in water-stressed and well-watered environments using low-density and GBS SNPs. Heredity. 2015. Vol. 114, no. 3, p. 291–299. DOI: http://dx.doi.org/10.1038/hdy.2014.99.

One of the most important applications of genomic selection in maize breeding is to predict and identify the best untested lines from biparental populations, when the training and validation sets are derived from the same cross. Nineteen tropical maize biparental populations evaluated in multienvironment trials were used in this study to assess prediction accuracy of different quantitative traits using low-density (∼200 markers) and genotyping-by-sequencing (GBS) single-nucleotide polymorphisms (SNPs), respectively. An extension of the Genomic Best Linear Unbiased Predictor that incorporates genotype × environment (GE) interaction was used to predict genotypic values; cross-validation methods were applied to quantify prediction accuracy. Our results showed that: (1) low-density SNPs (∼200 markers) were largely sufficient to get good prediction in biparental maize populations for simple traits with moderate-to-high heritability, but GBS outperformed low-density SNPs for complex traits and simple traits evaluated under stress conditions with low-to-moderate heritability; (2) heritability and genetic architecture of target traits affected prediction performance, prediction accuracy of complex traits (grain yield) were consistently lower than those of simple traits (anthesis date and plant height) and prediction accuracy under stress conditions was consistently lower and more variable than under well-watered conditions for all the target traits because of their poor heritability under stress conditions; and (3) the prediction accuracy of GE models was found to be superior to that of non-GE models for complex traits and marginal for simple traits.