Efficacy of the fungicide chlortalonil for bean disease control influenced by spray volumes and nozzles

Abstract

The aim of this study was to evaluate the efficacy of the fungicide chlortalonil in the control of bean diseases, influenced by spray volumes, fungicide rates and spray nozzles. On the field, two experiments were carried out: on the first, with the use of Pérola Variety, the initial symptoms of anthracnose, angular leaf spot and rust were observed 20 days after the emergency (DAE); and on the second, with the use of Ouro Negro Variety, the symptoms of the angular leaf spot and alternaria leaf spot were observed 25 and 45 DAE, respectively. A randomized complete-block design with four replications was used, in a factorial model 2 x 2 x 2 + 1: two spray nozzles (standard flat fan and hollow cone), two fungicide doses (0.75 and 1.5 kg ha^-1), two spray volumes (125 and 250 L ha^-1) and the control (non-treated plot). There was not influence of the nozzle type (flat fan and hollow cone) neither of the application volume (125 and 250 L ha^-1), used in the application of the fungicide chlortalonil, in the control of anthracnose, angular leaf spot or alternaria leaf spot as well as in the bean yield. The chlortalonil has provided a good control for the diseases, increasing the bean yield.