This book is an about research work on Bio fertilizer. It summarizes the research entitled "Extent of adoption of Bio fertilizer by farmers in Bhadohi district of U.P." The findings of the present study would help to understand the attitude of farmers regarding use of biofertilizers. The present study will provide useful guidance for knowing and understanding various biofertilizers used by the farmers. The finding of the study would also be helpful to understand the constraints faced by the farmers in adoption of biofertilizers and to obtain the suggestions to overcome the constraints faced by them. He successfully completed his research entitled "Extent of adoption of Bio fertilizer by farmers in Bhadohi district of U.P