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ResumenEl ajo en México es uno de los cultivos de hortalizas más rentables, más del 83% de esta superficie es aportada por los estados de Zacatecas, Guanajuato, Sonora, Puebla, Baja California y Aguascalientes.La pudrición basal ocasionada por Fusarium spp. se encuentra ampliamente distribuida a nivel mundial; esta enfermedad se ha convertido en una limitante en zonas productoras de cebolla y ajo, no solo en México, sino también en otros países, En México, se ha informado la presencia de Fusarium oxysporum en plantas en Guanajuato y en semillas de ajo en Aguascalientes. En el estado de Morelos se ha reportado la presencia de Fusarium culmorum en cultivares de cebolla. Asimismo, en Aguascalientes se tienen antecedentes de otras especies como Fusarium proliferatum, Fusarium verticillioides, Fusarium solani y Fusarium acuminatum. Para este trabajo se planteó como objetivo identificar las especies de Fusarium encontradas en los estados de Zacatecas, Guanajuato y Aguascalientes, y evaluar su patogenicidad. Se realizaron recolectas de plantas con síntomas de la enfermedad en los estados antes mencionados. De los muestreos realizados se identificaron las especies F. oxysporum, F. proliferatum, F. verticillioides, F. solani y F. acuminatum; las cepas de Aguascalientes identificadas como AGS1A (F. oxysporum), AGS1B (F. oxysporum) y AGSY-10 (F. acuminatum) fueron las que presentaron bajo condiciones de invernadero un mayor índice de severidad.AbstractGarlic 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.

Cascalote (Caesalpinia cacalaco) is a tree located in Pacific Mexican coast, and it is an excellent source of phenolics as gallic and tannic acids used in Mexican tannery industry, and with a potent antioxidant and antimutagenic activities. Based on the phenolics properties, these compounds present potential antimicrobial activity against a myriad of microorganisms. Thus, in this study it was evaluated the antimicrobial activity of cascalote phenolics against phytopathogenic fungus Colletotrichum lindemuthianum which causes anthracnose disease in common beans (Phaseolus vulgaris). The results indicate that cascalote phenolics have in vitro fungistatic activity against C. lindemuthianum races R-0 and R-1472. Moreover, these compounds provoked on the whole, in vitro inhibition of spores germination and cellulase and polygalacturonase activities in these fungi. In vivo assays with cascalote phenolics under greenhouse conditions using susceptible cv. PI 206272 of common bean resulted in a good protection against anthracnose severity especially as a preventive treatment. Several aspects of the results and implications on the potential use of cascalote phenolics as organic antifungal are discussed.

Early in the plant defense response against pathogens, transcription of specific genes is activated. We studied the genes up-regulated in the early resistance reaction of Phaseolus vulgaris against Colletotrichum lindemuthianum. The effect of the light–dark transition, ultraviolet-(A–B) light, and temperature stress on these genes was also evaluated. A calcium-binding protein and previously identified SUMO genes were over-expressed in the plant reaction to pathogen and under environmental stress. These genes appear to act as integrative signals and convergence points in early plant responses to pathogens and several forms of environmental stress. The calcium-binding protein gene was present in both plant and fungi genomes.