Influência do sistema de irrigação na incidência e nas perdas ocasionadas por Begomovirus na cultura do feijoeiro, Phaseolus vulgaris L. (Leguminoseae)

Abstract

The common bean (Phaseolus vulgaris L.) is a very consumed leguminous in Brazil it have essentials nutrients for the human health. The disease occurrence and inadequate management make difficult its Cultivation and affected the quality of that culture. Among the diseases most important, are the viruses caused by Begomovirus, show off Bean golden mosaic virus (BGMV). The high severity of disease caused by geminivirus, is mainly due to the absence of varieties resistant to the pathogen and also to the increased population of the insect vector, commonly called "whitefly" (Bemisia tabaci). This project had as main objective to evaluate the influence of three different irrigation systems in the incidence and the losses occasioned by Bean golden mosaic virus (BGMV) in the bean (Phaseolus vulgaris). The experiment consisted of three irrigation systems (drip, sprinkler and micro sprinkler) on bean plants grown in an area in the centro de ciências agrárias and was assessed for two consecutive years (October 2006 to January 2007 and October 2007 to January , 2008). The viruses incidence was determined based on number of symptomatic plants in relation to the total of plants present in parcel of 1 m2 randomly distributed in the experimental area. The golden mosaic effect in production was studied in two ways: relating production (grains weight) with the plot to incidence of the disease in this plot and comparing healthy and infected plants production. It was found that irrigation system influenced the viruses incidence, drip result in highest incidence (62.13%), and sprinkling shortest (16.74%), but did not differ statistically from the micro sprinkling. There was no correlation between incidence to golden mosaic and production in the plots, but when it was compared to production of healthy plants and disease plants found a higher three times production in healthy plants about plants disease.