Intercropping for management of insect pests of castor, ricinus communis, in the semiarid tropics of India

Abstract

Intercropping is one of the important cultural practices in pest management and is based on the principle of reducing insect pests by increasing the diversity of an ecosystem. Onfarm experiments were conducted in villages of semiarid tropical (SAT) India to identify the appropriate combination of castor (Ricinus communis L.) (Malpighiales: Euphorbiaceae) and intercropping in relation to pest incidence. The diversity created by introducing cluster bean, cowpea, black gram, or groundnut as intercrops in castor (1:2 ratio proportions) resulted in reduction of incidence of insect pests, namely semilooper (Achaea janata L.), leaf hopper (Empoasca flavescens Fabricius), and shoot and capsule borer (Conogethes punctiferalis Guenee). A buildup of natural enemies (Microplitis, coccinellids, and spiders) of the major pests of castor was also observed in these intercropping systems and resulted in the reduction of insect pests. Further, these systems were more efficient agronomically and economically, and were thus more profitable than a castor monocrop. © This is an open access paper. We use the Creative Commons Attribution 3.0 license that permits unrestricted use, provided that the paper is properly attributed.