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Background. Sustainable agriculture promotes the use of mineral and biological origin inputs that act as plant growth stimulants, such as zinc oxide nanoparticles (NPsZnO) and rhizospheric microorganisms, which have positively intervened in the physiological response of plants, due to their unique properties. Objective. To evaluate the effects of NPsZnO applied via foliar and drench, and of rhizospheric microorganisms on the vegetative growth and biomass of tomato plants. Methodology. The doses of nanoparticles were applied at: 0, 10 and 30 mg·L-1 and in microorganisms 0 and 10 spores·mL-1. The variables evaluated were: plant height, stem diameter, number of leaves, leaf area, root length and volume, and total biomass. Results. It was observed that plant height, stem diameter and number of leaves were higher with the interaction of 10 mg·L-1 of NPsZnO and the microbial consortium. The root length decreased 25.88% with the foliar application of 30 mg·L-1 NPsZnO. Root volume decreased 18.49% with the drench application of 30 mg·L-1 NPsZnO and decreased 29.55% with the foliar application of 10 mg·L-1 NPsZnO. The total biomass increased 15.65% and 28.81%, respectively with the foliar application of 30 mgL-1 of nanoparticles and when 30 mg·L-1 of NPsZnO was applied in interaction with the microbial consortium. Implications. Although root length and volume had a negative effect with the application of NPsZnO, plant height, stem diameter, number of leaves and total biomass structural components for fruit production in tomato plants were promoted by the application of NPsZnO in interaction with rhizospheric microorganisms by generating synergism. Conclusion. The dose of the nanoparticles, the application method and the microorganisms in the substrate showed positive synergism in the growth and biomass of tomato plants.

Reduction in pests targeted by Bt cotton is widely studied; however, other phytophages not affected by Bt cotton-expressed toxins are increasing, suggesting these potential pests might occupy ecological niches of primary pests and become new key pests requiring use of broad-spectrum insecticide. During the 2017 spring-summer crop season, insects were collected on 10 genetically modified (GM) hybrids of cotton (Gossypium hirsutum L.), planted at “Rincon del Buitre” ranch, belonging to “Universidad Autonoma Agraria Antonio Narro” (UAAAN) at San Pedro, Coahuila, Mexico. The 13,422 phytophagous insects collected from GM cotton were in five orders: Coleoptera, Diptera, Hemiptera, Lepidoptera, and Thysanoptera; ≈12,766 of the individual insects were in Hemiptera, mainly whiteflies (Aleyrodidae), for a total of 657 other insects collected. Coleoptera were 18.5% of the families, 19.4% of species, and 6.6% of individuals; Diptera had 29.6, 27.8, and 17.2%, respectively; Hemiptera (without Aleyrodidae) had 25.9, 27.8, and 18.9%, respectively; Lepidoptera had 18.5, 19.4, and 44.6%, respectively, and Thysanoptera had 3.7, 2.8, and 2.5%, respectively. Species with more individuals than 5% of the total were Anagasta kuehniella Zeller (32.7%), Spodoptera exigua Hubner (11.0%), Epichlorops sp. Becker (10.7%), Lygus oblineatus Say (9.0%), Diabrotica balteata Leconte (6.9%), Anthonomus grandis Boheman (5.9%), and Bemisia tabaci Gennadius (≈12,766 individuals). Species with greatest incidence among cotton hybrids were Epichlorops sp. (70%), L. oblineatus and D. balteata (each 60%), and A. grandis and Aphis gossypii Glover (each 30%). Monitoring increasing abundance of secondary pests on Bt crops can indicate if the pests threaten sustainable production of the crop.

La diversidad del maíz (Zea mays L.) en México es amplia y aún existe la necesidad de llevar a cabo trabajos que permitan discernir la variación dentro y entre grupos raciales y establecer colecciones de referencia racial para su entendimiento. Se valoró la diversidad morfológica de poblaciones representativas de 10 razas de maíz de México. En el ciclo primavera-verano de 2010 se establecieron experimentos con 88 accesiones representativas de las razas Bofo, Celaya, Coscomatepec, Dulce de Jalisco, Elotes Occidentales, Mushito, Palomero de Jalisco, Serrano de Jalisco, Tablilla de Ocho, y Zamorano Amarillo, en las localidades de Roque, Guanajuato y Ciudad Guzmán, Jalisco, bajo un diseño experimental de bloques incompletos, se midieron 30 caracteres morfológicos. El análisis de varianza indicó diferencias significativas entre las accesiones para todos los caracteres (variables). El análisis de repetibilidad reflejó que 16 caracteres presentaron un coeficiente ≥3, éstos fueron los menos afectados por el ambiente. En el análisis de componentes principales y conglomerados hubo variación dentro y entre razas, con una dispersión continua, que permitió identificar cuatro complejos raciales. El grupo I lo integraron accesiones de Bofo, el II de Celaya, el III de Dulce de Jalisco y el IV de Elotes Occidentales, las razas restantes se agregan en su mayoría en el grupo II como subgrupos. Este estudio confirmó agrupamientos de accesiones en razas bien definidas y representadas en los bancos de germoplasma. Es necesario realizar estudios más profundos en razas con pocas accesiones para lograr una mejor definición racial.

La producción de calabaza (Cucurbita pepo L.) para verdura o calabacita bajo cubierta presenta dificultades por la falta de polinización, por tal razón, la partenocarpia es una alternativa para generar variedades de calabacita de invernadero, por lo que actualmente se realizan esfuerzos en la búsqueda de partenocarpia genética que no requiera del estímulo de la polinización, ni por factores fisiológicos a fin de que el fruto se desarrolle en forma normal hasta la madurez fisiológica. Se estudiaron molecularmente 46 genotipos partenocarpicos de calabaza arbustiva tipo round zucchini obtenidos en la Universidad Autónoma Chapingo. El objetivo fue caracterizar e identificar la diversidad genética entre los genotipos a partir de la variabilidad obtenida mediante marcadores genéticos moleculares como los microsatélites del tipo ISSR (inter secuencias simples repetidas) y RAMP (polimorfismo de microsatélites amplificados al azar). Se utilizó (GATA)4 como iniciador de ISSR y la combinación de (GATA)4 con cuatro iniciadores de secuencia aleatoria de la serie A de Operon (OPA05, OPA10, OPA13 Y OPA19) para RAMP. Con las dos técnicas se obtuvo un total de 43 loci polimórficos, seis loci amplificaron con ISSR y 37 loci con RAMP. El porcentaje de loci polimórficos para ISSR fue de 100%, mientras que para RAMP fue de 91.8% de polimorfismo, se encontró alto grado de relación genética entre los genotipos partenocarpicos. Se formaron cinco grupos para ISSR y cuatro para RAMP, con distancias génicas entre 0.72 a 1.

Jatropha curcas L. hosts a wide variety of insects, but temporal variation in the composition of organisms (beta diversity) associated with crop farming has not been determined. Knowing the diversity and ecological role of its entomofauna are elements to develop management strategies for potential vulnerability of an agroecosystem. In this research, diversity, composition, and temporal turnover of insect species associated with cultivation of physic nuts were evaluated at Morelos, Mexico. During the second flowering period, 1,447 individuals in 13 orders, 106 families, 162 genera, and 190 species were collected; Hemiptera, Coleoptera, Diptera, and Hymenoptera comprised 89.9% of the individuals. Families Cicadellidae, Miridae, Chloropidae, Nitidulidae, and Chrysomelidae were most abundant. Insect alpha diversity, richness (0D), Shannon (1D), and Simpson (2D), did not show significant differences. Analysis of the composition of insect species using beta diversity (βSOR) showed a change of 0.37 ± 0.02 species. Piercing-sucking and chewing insects were the most diverse functional groups, of which at least 45 species are pests. The research should be complemented with more field observations in the Jatropha curcas crop. Results emphasized the need to consider different diversity aspects for appropriate crop management strategies.

Background. The Jatropha curcas species can be reproduced asexually by stakes, grafting and meristem cultivation, however, the main way to establish plantations is by means of botanical seed of high physiological quality that will ensure the germination and development of vigorous plants. Objective. To evaluate the variations in physiological and biochemical quality in stored seeds of J. curcas caused by accelerated aging deterioration method in different periods of exposure time. Methodology. Seeds with 75 days of storage were subjected to aging periods of 96, 72, 48 and 24 h at 40 ± 1 °C and 100 % relative humidity. Treated seeds were measured by germination percentage (PG), electrical conductivity (EC), protein content (CProt), fatty acids (CLip), peroxidation (IP). The lowest germination loss was obtained at 18 days in seeds with 24 h of treatment (93 %), and with 96 h they did not germinate (0 %). The EC identified progressive cell deterioration during the imbibition process (after six hours). The IP rose due to the moisture gain in the seed during the treatment period. The CProt and CLip had minimal variation. Conclusion. The physiological and biochemical quality of the Jatropha curcas seed showed serious variations with exposure to different periods of accelerated aging; It can withstand up to 72 hours of aging at 40 ± 1 °C and 100 % relative humidity before losing its viability.

Las chicharritas (Cicadellidae) son un grupo de insectos de importancia fitosanitaria; sus danos varian desde alteraciones fisiologicas y necrosis, producto de sus habitos de alimentacion y oviposicion, hasta intensas infecciones causadas por los virus y otros patogenos que trasmiten. El trabajo tuvo como objetivo evaluar la diversidad y abundancia de especies de chicharritas en una plantacion comercial de pinon (Jatropha curcas L.) en Morelos, Mexico. Se capturaron 372 especimenes de Cicadellidae, distribuidos en 10 generos; de estos, los mas abundantes fueron Draeculacephala (41.4%), Oncometopia (18.0%), y Dikrella (15.6%). El mayor numero de individuos (132) se colecto en el estrato medio de los arboles de pinon. Los valores de los indices de diversidad de Shannon-Weaver (H′ = 0.60 bits/individuo) y Simpson (Dsi = 0.33 bits/individuo) revelaron baja diversidad poblacional y de moderada a baja dominancia entre los generos recolectados. La mayor riqueza de generos se localizo en octubre y de especimenes en noviembre. Estos resultados enriquecen la informacion faunistica de los cicadelidos y el conocimiento de los estratos arboreos en que regularmente se refugian; pero sobre todo, se identifico la presencia de generos con gran potencial para afectar diversas especies de plantas de interes agricola.

Huitlacoche or corn smut, Ustilago maydis (DC.) Corda, is a biotrophic fungal pathogenic. The scales that grow in ears of maize, Zea mays L., are used as fresh or raw vegetables. In some regions of Mexico, maize is planted to harvest “huitlacoche”, a crop also susceptible to attack by insect pests that affect its quality. The purpose of this study was to recognize entomofauna in maize ears infected with huitlacoche (corn smut) and identify pest species that attack huitlacoche in five maize hybrids. We collected a total of 515 specimens in four orders, seven families, and 11 species. The orders Coleoptera and Lepidoptera comprised 71.4% of the total number of families, 81.8% of the species, and 99.6% of individuals. The percentage of damaged ears ranged from 47.5 to 65.0%. Species best represented were Cotinis mutabilis (Gory and Percheron), Spodoptera frugiperda (J.E. Smith), Heliothis virescens (Fabricius), and Carpophilus lugubris Murray considered primary pest of huitlacoche because they were present in all maize studied. Shannon-Wiener diversity (0.592 bits per individual) and Simpson (0.302 bits per individual) indices showed less diversity of individuals and moderate species dominance. Greatest richness of species was in hybrids ‘AN388’ and ‘H-318’, each with seven.