Soils and Crop Health in Rice–Wheat Cropping System Under Conservation Agriculture Scenario

Abstract

Rice–wheat system (RWS) is the most predominant cropping system in Indo-Gangetic plains (13.5 million ha). The RWS is favored by farmers over other cropping systems due to comparatively high yields resulting due to use of improved high-yielding varieties of rice and wheat, higher returns per ha, comparatively low incidence of pests, easy market for wheat and rice, mechanized farming suitable for RWS, and favorable policies of governments. The sustainability of RWS, however, also depends on soils and plant health. Emphasis is, therefore, given in recent years in reducing the cost of cultivation of RWS and making the system sustainable and soil in good health. The soil health largely depends on the organic carbon contents in soil. The organic carbon contents in soils of RWS are adversely affected due to removal and burning of crop residues after harvest of rice and wheat. Conservation agriculture is therefore opted in India and in other Asian countries to enhance soil health. The task of keeping beneficial soil microflora is difficult due to different field conditions needed in rice and wheat. The present review has compiled the information on research done on soils and crop health of RWS under conservation agriculture. The subject is comparatively new and therefore there is need to generate data by conducting long-term experiments on soil, and crop health of RWS may be affected in the future due to changes in microbial population in the field. The role of suppressive soils on soil-borne inocula of plant pathogens and disease incidence may also be studied in RWS.