ABSTRACT
The environment of a crop constitutes both soil and aerial, as part of the plant is inside the soil and the other part is exposed to the aerial atmosphere. The soil biological environment constitutes the living organisms (micro-flora) present in the soil and the resultant reactions like mineralization, immobilization etc. The soil management part of agronomy deals with the manipulation of soil environment for better crop growth. When the soil is subjected to tillage at optimum moisture, crumb structure is developed so that loss of soil by erosion is greatly reduced. Soil air can be controlled mainly by providing good drainage facilities. In case of submerged soils, most of the air escapes from the soil pores and air is present only in few pockets of subsoil. The activity and number of soil organisms can be modified by management practices so as to provide suitable environment for plant growth. Soil microflora is mainly composed of bacteria, fungi and actinomycetes.
