Efficacy of fungicides against powdery mildew of cucumber (Cucumis sativus L.)

Abstract

Erysiphe cichoraciarum DC. is the pathogen causing the powdery mildew disease that affects cucumber, which is a significant fungal disease that causes significant yield losses. With the following objectives in mind: effectiveness of fungicides in field conditions, effect of fungicides on conidial germination inhibition of powdery mildew, correlation of weather parameters with percent disease intensity, yield of cucumber per plot, and B:C ratio at the Department of Plant Pathology, College of Agriculture, Nagpur (MS), the current study was conducted to evaluate the intensity of the disease and develop appropriate management practices under field conditions during Rabi season 2023. According to the disease management study, all six fungicides were tested in the field against powdery mildew of cucumber and significantly reduced the disease's intensity compared to the unsprayed control. Three sprays of Azoxystrobin 23% SC (0.1%) were found to be the most effective fungicidal treatment, followed by Propiconazole 25% EC (0.1%) and Fluxapyroxad 250 g/l + Pyraclostrobin 250 g/l SC (0.1%), with minimum mean percent disease intensity recording 19.01, 22.22, and 27.89 percent disease intensity, respectively, with fruit (80.00 q/ha), (70.00 q/ha), and (67.65 q/ha), respectively. Six fungicides were tested by doubling the concentration under in-vitro conditions at room temperature against Erysiphe cichoracearum for inhibition of conidial germination, and the results showed that all the fungicides inhibited conidial germination 100 Percent, except the treatment metrafennone 500 g/SC (0.08%), which showed conidial germination inhibition (66.73%).