Microbes in Management of Fungal Diseases of Grape

Abstract

In India, grapes are commercially cultivated in the state of Maharashtra and some districts of Karnataka and Tamil Nadu which are characterized by warm, humid and intermittently wet or cloudy weather. Viticulture practices and grape pathology in these tropical regions is vastly different from that in temperate regions, necessitating greater emphasis on microbial interventions for disease management. Three fungal diseases namely, downy mildew, powdery mildew and anthracnose are the major threat to sustainable viticulture and cause great economic loss to growers. The high susceptibility of commercial grape varieties, presence of abundant inoculum in vineyards, and favourable weather for most part of the year, have a cumulative effect and disease outbreaks occur in a very short span of time. Dependence on chemicals alone has led to increase in cost of cultivation, development of fungicide resistance in pathogens, and presence of fungicide residues at harvest; apart from environmental concerns on continued and high use of fungicides. The use of naturally occurring microbes for biological control of diseases and also for induction of systemic resistance in susceptible grape varieties against these diseases is a safer and sustainable option. Worldwide researchers are searching for efficient microbes for management of grape diseases in vineyards and postharvest and this article is a compilation of their work.