Efficacy of fungicides and bioagents against Stemphylium blight of onion.
The efficacy of Pseudomonas fluorescens and hexaconazole in controlling Stemphylium botryosum [Pleospora herbarum] causing blight in onion cv. N-53 was determined in a field experiment conducted in Ranchi, Bihar, India during the rabi season of 1998-2000. The methods of application used were seed treatment, root dip or foliar spraying, used alone or in combination. All the treatments reduced the severity of the disease compared to the control, with hexaconazole treatment resulting in lower disease severity compared to P. fluorescens treatment. Crop yield was higher with hexaconazole than P. fluorescens treatment. Within treatments, twice foliar spraying resulted in the lowest disease severity in onion and highest yield.