Synopsis Biodiversity is rightly considered as an index of sound health of habitat and strong base for better evolution. It entails all forms of biological entities inhabiting the earth--including prokaryotes and euckaryotes. Man has always been fascinated by the biological diversity and has exploited it enormously for his own needs. In this venture, he has not only destroyed the natural biodiversity but has also enhanced the chances of health and environmental problems. To create awareness an attempt has been made to discuss various aspects of biodiversity at one platform. The present festschrift volume contains 40 reviews/research papers that will provide a new sight in basic and applied researches related to plant and microbial diversity. It mainly includes fungal diversity, biological pest management, bio-inoculation, stress resistance, aerobiology, plant disease, and microbial application in industries etc. The papers are invited ones and the authors bear the responsibility for their interpretation, literature citation and scientific names. We are thankful to the contributors for their cooperation.