IPM in Rice-Wheat Cropping Systems

Abstract

Rice–wheat cropping system is one of the most important production systems, which contributes a major share in the production of both the crops in Indo-Gangetic plains. This covers the area of 13.5 m ha of cultivated land covering across four countries, namely, Bangladesh, India, Nepal, and Pakistan. Among the several productivity constraints, namely, poor water management, nutrient deficiencies, the occurrence of several pests, diseases, and weeds are of utmost importance. Since R–W system contribute major share in the food bowl of the country hence constrains related to productivity need to be resolved with a minimum adverse effect on the quality of products, food chain, and biodiversity. Rice wheat cultivation in a continuous sequence; year after year reflects a regular increase in the 138population dynamics of several pests, pathogens, and ultimately yields loss of both the crops. In addition, this system also favors a heavy population of selective weeds. Adopting the practices based on principles of integrated pest management (IPM) and INM with a target of minimizing pests, diseases, and weeds thereby the quantity of agrochemicals can be minimized. Several insect pests, diseases, and weeds, which need to be monitored frequently, harm rice and wheat both. Based on monitoring and economic threshold level of specific crop enemy, strategic decision has to be taken for the application of specific management practices. The management practices should be decided in a long-term perspective and also in the context of sustainability of the environment and biodiversity as well. Several cultural practices and antagonists and natural enemies have been developed/identified, tested, and validated for the management of insect pests, diseases, and weeds, which can be effectively used for managing the insect pests, diverse pathogens, and weeds in both the crops. Several adopted cultural practices have been found to be quite effective in minimizing weed population and are commonly being used by farmers. Pest and disease specific resistant cultivars have also been developed, notified, and released in both the crops for different agroclimatic zones against important insect pests and diseases, which should be adopted with an aim to manage these enemies using host resistance. However, need-based chemicals may also be applied if there is no option and crop losses are supposed to be very big. Several IPM modules for rice, wheat individually, also as a system approach have been mentioned and discussed in this chapter.