In India sugar industry is the second largest agro-based industry next only to textiles. Sugarcane yield is markedly influenced by soil fertility, climate, variety, moisture stress, weeds, insect pests and diseases. The estimated loss from insect pests account to nearly 20 per cent in cane yield. The recent havoc of previous decade Sugarcane Woolly Aphid (SWA), Ceratovacuna lanigera Zehntner has been a new addition to the key pests of sugarcane. Due to monoculture, availability of food round the year, soft cane and high sugar varieties and favourable climatic conditions some of the minor pests have attained the status of major pests. In sugarcane ecosystem, though synthetic insecticides are effective do not find place due to difficulty in spraying, operational hazards, improper coverage of crop canopy, high costs and destruction of natural enemies treasure. During 2005, natural incidence of new fungus was noticed on SWA and spread over an area of 100 acres and caused more than 90 per cent pest control by inducing spectacular epizootics. This book contains isolation, mass multiplication, laboratory and field evaluation of the entomopathogenic fungus Acremonium zeylanicum.