Selection Varietale Des Genotypes De Lentilles Adaptes Aux Saisons Courtes Et Chaudes

Abstract

Lentil (Lens culinaris ssp culinaris Medikus) is a cool season food legume crop grown around the world for its role in human and soil health. With climate change, heat and drought have emerged as the most important abiotic stresses that affect lentil productivity in major crop producing areas. It is expected that the severity of these stresses will further increase in intensity and frequency with changing climate. One of the options to counter the effect of rising heat and drought stresses is to develop lentil germplasm adapted under such conditions. Therefore, the present study was undertaken to identify lentil germplasm tolerant to heat and drought at Terbol research station of International Center for Agricultural Research in the Dry Areas (ICARDA). The study involved evaluation of 80 germoplasm lines (50 wild relatives and 30 landraces) representing wide spectrum of diversity under plastic house by subjecting them to: 1) heat stress (greater than 20°C during night and greater than 35°C during the day at flowering time), 2) no stress with full irrigation, and 3) 50% water deficit through the life cycle. The experiments were undertaken between July 2018 and May 2019 in 'alpha-design' with two or three replications under different conditions. Observations were recorded on phenological traits such as days to germination, flowering and maturity, and yield components including biological yield, number of pods per plant, number of seeds per plant, and total seed weight. Pollen germination was also assessed at flowering time to observe the effect of heat and drought on pollen viability. The results showed significant reduction in yield and other traits under heat and drought stresses. The study resulted in identification of six germplasm lines of cultivated lentil (IG481, IG69497, IG75920, IG117678, IG117680, and IG156536) and three of wild relative, Lens orientalis (IG72743, IG116027, and IG135410) as tolerant to water stress. Similarly, six germplasm lines of cultivated lentil (IG5505, IG5582, IG69492, IG71175, IG73685, and IG73858) and six of wild relatives (IG72603, IG72864, IG116038, IG135410, and IG137423 of Lens culinaris ssp. orientalis, and IG72719 of subspecies tomentosus) were found tolerant to heat stress. Also it exits a genotype IG135410 of subspecies orientalis is tolerant to both stresses. These tolerant germplasm lines will be utilized in breeding program at ICARDA to develop climate smart varieties of lentil with tolerance to heat and drought and will also be shared and evaluated in target countries where lentil cultivation faces heat and water stress during different crop growth stage