Vol. 11, Issue 2 (2022)

Author(s):
Praveen Mangal, M Singh and Tejpal Bajaya

Abstract:
Cucumber (Cucumis sativus L.) is an important vegetable crop of Rajasthan as well as India and belongs to family Cucurbitaceae. Alternaria leaf spot disease of cucumber caused by Alternaria alternata is an important constraint to this crop in quality and monetary terms. A study was conducted to see the toxic effect of culture filtrate of Alternaria alternata on seedlings of three varieties (Cucumber Long, F-1 Hybrid Liberty and Summer Express-40) with four concentrations (25, 50, 75 and 100%) and 15,30, 45 and 60 days old culture filtrate. Among concentrations, 100 per cent concentration of filtrate was highly phytotoxic as it gave minimum seed germination (56.25%) and seedling vigour index (7185.94) as compared to untreated check (92.50% and 18615.63, respectively) on Summer Express-40 variety. In age old filtrate study, 60 days old culture filtrate was more toxic in lowering seed germination (41.25%) and vigour index (3557.81) of variety F-1 Hybrid Liberty over untreated (86.75% and 16485.31). Conclusively, it is clear that released exudates of the pathogen in soil may be phytotoxic and can reduce seed germination and vigour index of plants that ultimately results in economic loss to the end users.