Severidad de la roya en cultivos de frijol (Phaseolus vulgaris L.)

Abstract

The common bean (Phaseolus vulgaris L.) is an
important crop due to its nutritional properties, its
production is diminished by the diseases that attack
it. The objectives of this study were to identify the
pathogen, evaluate the incidence and severity of the
disease that affects bean crops in Tixtla, Guerrero,
Mexico. In the identification of the pathogen, leaves
with spots were collected for microscopy and
pathogenicity tests. For the incidence, the
percentage of diseased plants in the field was
obtained. In severity, a scale of damage to the leaves
was designed. The morphological characteristics of
the pathogen corresponded to Uromyces phaseoli
var. typica Arth. The damage due to incidence in the
plots was 05% of plants that presented severity level
5 (with rust in 100% of leaves), 10% of plants with
severity level 4 (75% of their leaves with rust), 15
% with level 3 (affected in 50% of leaves), 20%
presented level 2 (25% of leaves with rust), the rest
were healthy. The pathogen occurred on average in
50% of plants according to the incidence and
severity of the disease that was determined in this
region.