Preliminary evaluation of biocontrol agents against maize pathogens Exserohilum turcicum and Puccinia sorghi in field assays

Abstract

Exserohilum turcicum and Puccinia sorghi cause foliar fungal diseases that affect maize crop in Argentina. These diseases, northern leaf blight and commonrust respectively, are presented each year with different levels of severity affecting significantly the yield in susceptible hybrids. Disease control usuallyconsists in the use of resistant cultivars and chemical control. Biological controlas a preventive method is a viable alternative to evaluate. The aims of thisstudy were to evaluate the natural incidence of both foliar diseases in maizeafter application of two antagonists, to determine the survival of the antagonistsin the maize phyllosphere and to evaluate the effect of inoculation ongrain yield at harvest. Plants treated with both biological control agents showed significant reductions in the incidence of both foliar diseases. Innorthern leaf blight the reduction was higher than 50% during 40 days inplants treated with Bacillus spp. Moreover, grain yield was significantly higheras compared to control treatments