ADMINISTRATION OF POWDERY MILDEW (Oidium mangiferae Berth.) OF MANGO THROUGH DIVERGENT GERMPLASM

Powdery mildew of mango, incited by the fungus Pseudoidium anacardii (formerly known as Oidium mangiferae Berthet), is one of the most common, widespread and serious disease throughout the world and causes significant yield losses up to 90 per cent. It is one of the major limiting factors in its cultivation affecting both yield and fruit quality in Himachal Pradesh. Present investigation was undertaken with the objectives to screen the different cultivars under natural epiphytotic conditions to record their reaction. Eighteen and 23 cultivars of mango were screened under regular epiphytotic conditions at RHRS, Dhaulakuan and RHR&TS-Jachh (Nurpur) separately to decide their reaction against fine buildup of mango. The study indicated that during both the years of study the commercially grown cultivar Totapuri indicated respectably safe response with the most minimal obvious contamination rate (0.02 per unit every day) and AUDPC (1.16), though remainder of the cultivars displayed decently vulnerable to exceptionally helpless response while cvs. Pusa Surya, Gulab Jamun, Gurjeet, Banraj, Atkin, Tommy Atkin and Goa Mankard demonstrated reasonably defenseless response. The remainder of the cultivars displayed defenseless to profoundly susceptible responses indicating the role of local cultivars in incorporating powdery mildew resistance in future mango breeding programme.