Reintroduction of Extra Short Duration Pigeonpea (ICPL 88039) in Rice-Wheat Systems of the Indo-Gangetic Plains: RWC Technical Bulletin No. 9.

Rice–wheat cropping systems (RWCS) are managed on 10 million ha in the Indo Gangetic Plains (IGP) of India. Recent reports, however, indicate that the system is under fatigue and the growth rate of rice and wheat has started declining. Natural resources, particularly soil and water, are threatened because of their over exploitation. Water efficient legumes such as pigeonpea can play an important role in reversing the process of degradation of soil and water resources, and improving the production potential of RWCS. Among legumes, pigeonpea [Cajanus cajan (L.) Millesp] has been an integral part of RWCS and was widely grown in early sixties. However, agricultural polices of the Green Revolution era beginning 1970 focused on increased production through the introduction of input-responsive cultivars of rice and wheat, which not only replaced or marginalized the traditional long and short duration cultivars of pigeonpea but also made them unsuitable even to be used as a break crop in the existing RWCS. It is in this context that ICRISAT developed extra short duration pigeonpea (ESDP) cultivar ICPL 88039. This genotype was evaluated along with traditional cultivars for its suitability as a break crop to restore soil heath, and improve productivity of RWCS. A large volume of literature is available on studies related to the beneficial effects of legumes on the productivity of rice and wheat. In this bulletin, attempts have been made to briefly describe the process and important findings of reintroducing pigeonpea, particularly ESDP genotype ICPL 88039 in the pigeonpea–wheat rotation by scientists from Indian Council of Agricultural Research (ICAR), Rice–Wheat Consortium (RWC) of the Indo-Gangetic Plains, State Agricultural Universities (SAUs) and International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) in partnership with farmers. Efforts were made to identify the constraints and opportunities in growing ICPL 88039 in rotation with wheat for its long term sustainability and resource conservation in RWCS in the IGP. This technical bulletin provides information on the abiotic, biotic and socio-economical constraints that can limit ICPL 88039 production in the RWCS. Color photographs are included to facilitate identification of insect and diseases. A package of practices for ICPL 88039 is also included for use of the farmers, researchers and scientists