Micro-organisms and plant growth : The scope of recent soil microbiological research

Abstract

Early stages in the development of soil microbiology as a distinct branch of soil science witnessed ( 1) the association of micro-organisms with soil biochemical processes, notably nitrification, organic matter decomposition and liberation of plant nutrients; ( 2) nitrogen fixation from air, by organisms either in symbiosis with legumes or species free-living in soil; ( 3) the demonstration of mineral transformation by certain other bacteria. These pioneer developments associated with the researches of Kette, Warrington, Winogradsky and Beijerinck have been reviewed in the writings of Waksman ( 1932; 1938), Waksman and Starkey ( 1931) and Russell ( 1937).