Kachai Lemon (Citrus Jambheri Lush) is an exotic horticultural fruit from Eastern Himalayan region (Manipur) which has been accorded Geographical Indication (GI) registration tag. Unlike the other Lemon varieties grown in other parts of the world, Kachai Lemon is considered to be unique as it is a rich source of ascorbic acid, containing 45-57 mg/100ml juice. The juice content is 36-56 ml. per fruit. Certain fungal diseases of Kachai Lemon are airborne as there exists a correlation between the prevalence of fungal spores in the air and development of certain fungal diseases in Lemon orchards. The present book, therefore provides information about developing disease forecasting system leading to efficient control of Lemon orchard. The book should be especially useful for organic control of fungal diseases in this Horticultural crop.