INFLUENCE OF CANOPY MANAGEMENT PRACTICES TO REDUCE THE SEVERITY OF ANTHRACNOSE DISEASE OF GRAPES

Abstract

Anthracnose caused by Elsinoe ampelina(de Bary) shear is one of the important foliar diseases of grapes (vitis vinefera L.) in India. Gupta et al. (1981) recorded 50% yield losses in grapes due to infection of anthracnose disease in all aerial parts including inflorescence and berries. In West Bengal susceptible cultivars i.e. Pusa Seedless is usually infected due to its dense canopy and light berry cluster in every cropping season. The field experiment was conducted during 2011 and 2012 to manage the Anthracnose disease through integration of canopy management practices with fungicidal spray for minimizing the yield losses and also to detect the influence of lateral shoots on fruit yield. A susceptible cultivar i.e. Pusa Seedless was selected in a 6 years old vineyard at Birbhum, West Bengal. Under canopy management practices, treatments consisted of leaf removal, shoot removal and control. Leaf removal showed significant reduction in disease incidence (13.5%) and severity (1.9%) than control. Similarly shoot removal not only showed significant increase in lateral shoot development but also reduced the incidence (20.85%) and severity (8.9%). Yield components i.e. berry weight (g), number of berries/cluster, cluster weight (g) and fruit yield (Kg/vine) showed significant increase due to canopy management. The berry weight was significantly enhanced due to leaf removal (97.5 g) and shoot removal (96.0 g). Canopy exposure also increased the cluster weight (215.4 g and 226.0 g) as a result of leaf removal and shoot removal respectively. Total fruit yield was also enhanced in leaf removal (7.9 Kg/vine) and shoot removal (8.25 Kg/vine) over control (5.5 Kg/vine).The canopy management practices also increased the lateral leaf area (%) resulting better fruit yield. Even, when canopy exposure practices was combined with fungicidal spray as an integrated approach, significant results were obtained as compared to the sole use of canopy exposure practices. Hence, it may be stated that, integrated use of canopy management practices with fungicidal spray reduces the anthracnose disease as well as increases the fruit yield.