Distribution and Prevalence of Downy Mildew Disease on Cucurbits in Punjab

Cucurbit downy mildew caused by Pseudoperonospora cubensis is a major destructive disease affecting wide range of cucurbits which causes significant losses to the growers in terms of yield and fruit quality. The present study was conducted with an objective to assess the disease incidence and severity in Punjab under different agro-climatic zones. The survey conducted in various cucurbit growing regions of Punjab revealed that highest disease incidence was observed in Western Zone (36.41%) followed by Central Plain Zone (26.92%). The disease severity was highest in Western Zone (20.42%) succeeded by Central Plain Zone (15.62%), sub-mountain Undulating Zone (14.30%) and Western Plain Zone (12.79%). The overall mean disease incidence in Punjab state was 31.21 and 36.06 per cent during the year 2018-19 and 2019-20, whereas disease severity was 16.78 and 21.65 per cent in the respective years. Ludhiana and Sangrur emerged as the hot spot areas for the occurrence of downy mildew with disease incidence of 43.88 and 34.69 per cent, respectively. Among the different crops surveyed, the disease prevalence was maximum in cucumber (37.61%) and least in watermelon (22.00%). The hybrids cultivated in each cucurbit host reported to be more affected by the downy mildew as compared to the composites and land races.