The book highlights the fungal deterioration of herbal raw materials during storage in tropical and subtropical region, used in manufacture of Ayurvedic medicines. It provides information of fungal colonization and mycotoxin production in raw materials. The book explores the possible exploitation of higher plant essential oils as safe and ecofriendly alternative of synthetic fungitoxicants. Research findings in the book also giving information of bioactive potential in some plant essential oils where knowledge about them is still fragmentary. The book has been prepared to cater the needs of research students especially working on biopesticides/botanical pesticides and post harvest pathology of various substrates. The text is profusely illustrated with about 56 figures in the form of line diagram and photographs.