Development of molecular methods has paved the way to the study of microbial communities in soil. PCR-based DGGE (Denaturing gradient gel electrophoresis) analysis has proved to be useful in studying microbial community diversity and composition. Although plant and soil microbial communities are dependent on each other, as producer and decomposer, respectively in the terrestrial ecosystems few studies attempted to study soil microbial communities in relation to their linkages with plants in the grassland ecosystem. We studied community composition of soil bacteria and fungi by following PCR-based amplification of 16s rDNA and 18s rDNA fragments, respectively, in relation to their structural and functional linkages with plants in grasslands. This book is expected to be useful for the students and researchers interested in studying diversity of soil microbes and their role in ecosystem functions as well as for those who are involved in management and conservation of the grassland ecosystems.