Book information: -Title: Development of Rhizobiology in Sri Lanka. -Subtitle: Rhizobiology in Sri Lanka- Summary Rhizobiology is the study of soil bacteria belonging to the Genus Rhizobium. Different species of this bacterium is capable of forming symbiotic root nodules with nearly 90% of the species belonging to the Angiosperm Family Fabaceae (earlier known as Leguminosae). These nodulated plants are capable of directly converting the inert dinitrogen (N2) gas which constitutes 78% (by volume) of air to a combined, usable form. Unlike most organisms, these plants are therefore capable of growth and reproduction in the absence of combined nitrogen from other sources including nitrogen fertilizer. This property is invaluable in agriculture because a number of legume species are important food and forage crops that are widely cultivated all over the world.