Validation of Fungicide Spray Schedule of Conventional Apple Orchards under High Density Apple Orchard System against Scab and Alternaria Leaf Blotch

The purpose of the study was to find out efficacy of phenological stage based recommended fungicide spray schedule comprising seven sprays used in conventional apple orchards (apple cultivars grafted on seedling rootstocks) for the management of scab and alternaria leaf blotch of apple in high density apple orchards (cultivars grafted on clonal rootstocks) of Kashmir valley. Its application under high density apple orchard (cv. Red Delicious on seedling roostock) system provided inadequate control as compared to the standard check. The application of fungicide sprays at different phenological stages under high density orchard system provided 70.07 to 74.27 and 63.96 to 79.97 per cent control in leaf scab incidence and intensity, as against 93.89 and 95.17 per cent recorded in conventional orchard system, respectively. The sprays exhibited 63.96 to 70.31 and 63.21 to 68.61 per cent control in fruit scab incidence and intensity in high density orchard system as against 92.31 to 90.04 per cent in conventional system, respectively. However, in case of Alternaria leaf blotch disease 67.48 to 82.16 and 83.84 to 88.15 per cent disease control in incidence and intensity was observed as against 82.16 and 88.15 per cent in conventional orchard system.