The origin of the Division of Microbiology is traced to the Unit of Soil Microbiology, the Division of Soil Science & Agricultural Chemistry, and the Unit of Algology, then the Botany Division, amalgamated in 1961. The Division of Microbiology offers exciting opportunities for research and learning about beneficial and commensal microorganisms in agriculture over the past six decades. The Division of Microbiology has a critical mass of researchers with expertise spanning biochemistry, physiology, genetics, genomics, and microbial processes related to nutrient cycling, host plant-microorganism interactions, and waste decomposition. The passionate interests of the faculty and students in research and learning about microorganisms encompass diverse questions and use multiple approaches, from laboratory to field studies, to benefit society, specifically farmers. The Division of Microbiology gains from the in-house facilities and technical expertise to produce and distribute high-quality liquid and carrier-based microbial inoculants (biostimulants), formulate the standards for due approval by the Bureau of Indian Standards (BIS), and test the efficiency and purity of inoculants manufactured. 

The Division of Microbiology is the National Centre for advancing and providing holistic research and training in microbiological sciences focused on agriculture. The Division of Microbiology applies cutting-edge research tools and techniques to address critical and emerging issues of national and global concerns. The Division also contributes to human resource development, mentoring national and international students for their undergraduate, master's, and doctoral degrees and encouraging intra- and inter-institutional collaborative research. The Centre for Conservation and Utilization of Blue Green Algae (CCUBGA), affiliated with this Division, is a significant germplasm resource that conserves and provides microbial wealth for profitable gains nationally.