Resumen

TOSQUY-VALLE, Oscar Hugo et al. Reaction to angular leaf spot and bean genotypes productivity with and without fungicide application. Rev. Mex. Cienc. Agríc [online]. 2013, vol.4, n.1, pp.167-174. ISSN 2007-0934.

In central Veracruz, the angular leaf spot is a disease that affects bean yield. The purpose of the study was to determine the reaction to this disease, yield and profitability of bean genotypes with and without application of the fungicide mancozeb. The experiment was set up in the rainfed in 2011 in Rincón Grande, Orizaba, Veracruz, in a randomized block experimental design with four replications in factorial arrangement of treatments. We evaluated two mancozeb levels: 0 (control region) and 1.5 kg ha^-1 of commercial product and three bean genotypes: Negro Michigan (regional control) and the varieties Negro Jamapa and Negro Comapa. We measured the angular leaf spot and grain yield, which were analyzed and for the average separation we applied DMS at 0.05. We also performed a correlation analysis of both variables and an economic analysis to determine the profitability of the treatments. Without any fungicide application, the angular leaf spot decreased the yield (r= -0765 **). Negro Comapa and Negro Jamapa were tolerant to the disease and showed a better yield than Negro Michigan, which was susceptible. With the application of mancozeb, the plants showed less damage, an increase in yield higher than 800 kg ha^-1 and higher profitability in the three genotypes, without fungicide application. With Negro Comapa and Negro Jamapa we obtained benefit/cost relations of 2.69 and 2.67, quite higher than Negro Michigan (1.91).

Palabras llave : Phaseolus vulgaris L.; Phaeoisariopsis griseola; genetic resistance; chemical protection.