In this article we will discuss about the genetics of nitrogen fixing microorganisms. 1. Bacterial Nodulation Genes and Regulation of nod Gene Expression: In Rhizobium species, nodulation genes together with other symbiotic genes are located on large-plasmids (Sym plasmids). Sym plasmids vary from 50 to over 600 kb in R. leguminosarum bv. trifoli to 1200 […]