Apple scab caused by Venturia inaequalis (cke.) Wint is now prevalent in all the apple-growing region of India. It is serious in those areas which received good rainfall in spring and early summer months. Apple scab caused by Venturia inaequalis (cke.) Wint. is now prevalent in all the apple-growing region of India. It is serious in those areas which received good rainfall in spring and early summer months. The principles and methods of scab management are generally based on scab behavior. The knowledge of pre-disposing factors favorable to scab infection is pre-requisite for implementing the principles of control with prudence for effectivity. Protectant sprays are generally applied well after the infection has taken place but the symptoms are not manifested. The spray schedule would cover all stages viz., before, during and after infection and even the summer infection periods, Singh and Kumar, 2005. The stages of spray and choice of fungicides for application however are the cardinal factors determining the effectiveness of the control program, Singh and Kumar, 1999. Different management strategies have been developed to prevent the disease efficiently through 8-10 spray scheduled application of fungicides Gupta, 1985, Dar, et al., 1983; Singh and Kumar, 2005 besides, application of systemic and sterol inhibiting (SBI) fungicidal sprays depends on the prevailing weather conditions and competence of the producer. The cost of sprays accounts for 15-20 percent of the total maintenance expenditure on a tree. A spray schedules currently in vogue in Uttarakhand shall give insight of the strategy adopted to meet the disease challenge. Apple trees are attacked by a number of foliar diseases amongst which Scab, Marssonina blotch and Powdery mildew are foremost, apart from Sooty blotch and Fly speck which causes declining productivity of apple in this state. Powdery mildew (Podosphaera leucotricha (Ell. & Ev.) E. S. Salmon) affects the terminal growth adversely and reduces photosynthesis, transpiration, and carbohydrate content of the host, tree vigor and blossom production (Singh, 2006). Marssonina blotch (Marssonina coronaria (Ell. & J. J Davis) J. J Davis has been ravaging the apple plantations by causing mid-season defoliation (Sharma, 1999, 2001). Sooty blotch (Gloeodes pomigena (Schwein) Colby) and fly speck (Schizothyrium pomi (Mont. & Fr.) Arx.) cause superficial greenish black blemishes and render the fruits unmarketable. The loss due to above these diseases results in reduction of yield, deterioration of fruit quality, devaluation of fruit, premature leaf fall and increase in operational expenses on account of fungicidal sprays as required for combating the diseases. It requires many applications of synthetic fungicides for the control of apple diseases. The usage of apple fungicides varies from country to country and is frequently changing. The sterol-biosynthesis inhibiting (SBI) fungicides are generally highly affective for control of most of the apple diseases In Uttarakhand, the orchardist conducting timely fungicidal sprays with various fungicides as recommended by the GBPUAT, Hill Campus, Ranichauri and department of Horticulture from time to time coupled with cultural operations like collection, and five per cent urea spray for burning of fallen leaves during autumn have been able to protect their crop from the diseases. In view of this, the present study was undertaken to: (1) develop a spray schedule involving commonly available systemic and non systemic fungicides (II) evolve new EBI fungicides in schedule to provide multi-disease control in the apple orchards.

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