The use of nanoparticles (NPs) has generated an alternative pest control. The objective was to evaluate the insecticidal effect of zinc oxide nanoparticles (ZnO NPs), titanium dioxide nanoparticles (TiO2 NPs), and their combination on Bactericera cockerelli (Hemiptera: Triozidae) second-stage nymphs under laboratory and greenhouse conditions in tomato. The laboratory research was carried out with the leaf immersion bioassay method under a complete randomized design, and in the greenhouse by direct plant spraying under a randomized block design; in both designs, a control without NPs was added. Mortality was recorded every 24 h for 4 days. Both NPs in the laboratory and greenhouse showed toxicity to B. cockerelli nymphs. Results in the laboratory showed that NPs significantly caused increased mortality of 88, 99, and 100% 96 h after treatment of ZnO NPs, TiO2 NPs, and their combinations, at 1000, 100, and 250 ppm, respectively. Direct spray of plants in the greenhouse showed low mortality with 27, 32, and 23% after 96 h of ZnO NPs, TiO2 NPs, and their combinations, at 3000, 500, and 250 ppm, respectively. These results on B. cockerelli control seem promising. Nanoparticles as insecticides are a novel strategy, however, further investigation is required in field tests to obtain suitable efficacy for use in a pest management system.

Garlic in Mexico is one of the most profitable vegetable crops, grown in almost 5,451ha; out of which more than 83% are located in Zacatecas, Guanajuato, Sonora, Puebla, Baja California and Aguascalientes. Blossom-end rot caused by Fusarium spp is widely distributed worldwide and has been a limiting factor in onion and garlic production regions, not only in Mexico but also in other countries. The presence of Fusarium oxysporum has been reported in Guanajuato and Aguascalientes. Fusarium culmorum has been reported in onion cultivars of Morelos; and Fusarium proliferatum, Fusarium verticillioides, Fusarium solani and Fusarium acuminatum have been previously reported in Aguascalientes. The goal of this work was identifying the Fusarium species found in Zacatecas, Guanajuato and Aguascalientes, to assess their pathogenicity. Plants with disease symptoms were collected from hereinabove mentioned States. The samples resulted in the identification of: F. oxysporum, F. proliferatum, F. verticillioides, F. solani and F. acuminatum species; out of which Aguascalientes AGS1A (F. oxysporum), AGS1B (F. oxysporum) and AGSY-10 (F. acuminatum) strains showed higher severity under greenhouse conditions.

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Candidatus Liberibacter solanacearum (CLso) es una bacteria fitopatógena Gram-negativa, limitada al floema en solanáceas y no cultivable in vitro. Es transmitida de manera vertical y horizontal por el psílido Bactericera cockerelli. En México se asocia como responsable de la enfermedad "permanente del tomate", "punta morada de la papa" (Zebra chip) y "variegado del chile". Los síntomas causados por la bacteria varían según el cultivar y la etapa de crecimiento del hospedante pero consisten principalmente en amarillamientos y deformación de la lámina foliar, debido a la alimentación del vector y la colonización del patógeno. Las infecciones ocasionadas por CLso reducen la calidad del producto y el valor comercial en el mercado. La presencia de esta bacteria ha sido detectada en los estados de Coahuila, Sinaloa y Guanajuato, México a través de técnicas moleculares; mientras que el control de la enfermedad se encuentra enfocado en el vector, mediante prácticas culturales y la aplicación de agentes químicos y biológicos. Por lo anterior el objetivo del trabajo es puntualizar la situación actual de la distribución de CLso en México, los métodos de diagnóstico y las estrategias para el manejo integrado de la enfermedad y el vector.