Identification of castor parental lines with drought tolerance

Abstract

Castor is an important oilseed crop of India. It is generally grown in poor and marginal soils without irrigation, resulting in yield reduction. Evaluation of genotypes under stress is useful in breeding programs because it allows a direct estimate of drought tolerance or susceptibility of individual genotypes. Hence, an experiment was conducted at Narkhoda farm of ICAR-IIOR to evaluate 59 parental lines for drought tolerance during late rabi, 2018 by imposing drought stress from 45 DAS till harvest. Crop growth viz; plant height, node number, stem girth and branch production reduced after 70 days in stress. Effective spike length (ESL), capsule number, spike weight and seed weight of primary and secondary spikes also reduced with drought stress. Drought intensity was very high (intensity index is 0.612) which resulted in an average seed yield reduction of 58% with drought stress. Among the studied genotypes, 16 parental lines with 31-51 g/plant seed yield in stress with <1.0 drought susceptibility index (DSI) were selected which include: DCS-9, DCS-104, DCS-105, DCS-106, DCS-110, DCS-119, DPC-9, DPC-16, DPC-18, DPC-23, DPC-28, ICS-121, ICS-127, ICS-133, ICS-134 and ICS-322.