Efficacy of natural products and fungicides against powdery mildew of ber

Abstract

Indian jujube or ber (Ziziphus mauritiana Lamk.) is one of the most common fruit, indigenous to an area joined from India to China. Powdery mildew of ber incited by Oidium erysiphoides f. sp. ziziphi, Yan and Wang is the most important disease that causes maximum reduction in yield and quality of ber fruits. Exclusive reliance on fungicides for the control of disease of various crops resulted in residue and environmental hazards. Therefore, in recent years, efforts are being diverted to employ higher plants, natural products and their derivatives as a tool for integrated disease management because they do not cause bio-accumulation, bio-magnification and environmental pollution. In present investigation, six natural products (buffalo milk, cow milk, garlic extract, neem oil, mustard oil, butter milk/chhach) were evaluated for their efficacy against powdery mildew of ber. The jujube or ber is an ancient fruit of India and China. It was one of the prominent fruits on which the sages in ancient India lived during the Vedic age and lived even today. Ber is a hardy crop which grown in arid conditions of Rajasthan, characterized by sandy soils, scanty rainfall (400-600mm), thermal oscillations (5-35 0C) and low relative humidity. Therefore, the area of cultivation is increasing in this zone (arid and semi arid) and is expected that in near future ber will be a leading fruit crop of arid zone. The cultivation of ber requires the least input and care. In natural products maximum intensity over control was observed with garlic extract followed by neem oil, mustard oil, cow milk, buffalo milk and least effective was butter milk. Among the five systemic and non systemic fungicides (difenoconazole, dinocap, hexaconazole, tridemorph and wettable sulphur) tested against powdery mildew of ber, the maximum reduction in disease intensity over control was observed in dinocap (0.1%) with lowest per cent disease intensity (9.60) followed by hexaconazole, wettable sulphur, tridemorph and least effective was difenoconazole.