EVALUACIÓN DE LA PATOGENEICIDAD DE LA MICROBIOTA FÚNGICA ASOCIADA A CINCO VARIEDADES AUTÓCTONAS ESPAÑOLAS DE JUDIÓN (<i>PHASEOLUS COCCINEUS L.</i>).

Abstract

The micoflora from 5 runner bean landraces (Phaseolus coccineus L.), coming from an organic farmer in Oteruelo del Valle (Rascafría natural Park, Madrid), and 5 cultivars included in the Common Catalogue of commercial varieties of the European Union was characterized. A total of 3200 seeds of all lots harvested in 2005-2006 campaign were analyzed. 5 seeds of each sample were placed in Petri plates with agar-dextrose-potato medium (PDA) and also 6 seeds per sample in humid chamber. At least 220 seeds were analyzed in 20 repetitions per sample. Specific analyses using a selective medium with all the samples were made to identify the presence of Fusarium writing down the number of present species in each tested seed. A total of 11 different fungal species were identifi ed. The presence of the different genus varied among cultivars, being much more smaller, although not absolutely absent, in the commercial seeds. In the isolated fungal microbiota, it is neccesary to emphasize, due to its potential patogeneicity or its capacity for mycotoxins or secondary metabolites production, genus such as Aspergillus, Alternaria or Rhizoctonia. In the second part of the study, the effect that these fungi have on the germination of the seeds was evaluated. Patogeneicity tests were carried out on a total of 200 seeds of Phaseolus vulgaris var. Calgary. The inoculations were made with two isolates of the six genus of greater quantitative importance of the study (Aspergillus, Penicillium, Ulocladium, Rhizopus, Cladosporium and Alternaria).