Screening lentil (Lens culinaris Medik.) germplasms for heat tolerance

Climate change and subsequent global temperature rise has become a threat to pulse production. Terminal heat stress results in forced maturity with low yields. The most worrying part of prediction is the estimated increase in the winter and summer temperatures by 3.2 degrees and 2.2 degrees celsius, respectively by 2050. So tolerant and early maturing germplasms that are well suited to heat stressed environment are needed to enhance and sustain lentil production in present condition. Studies were conducted to screen a large number of lentil germplasms for heat tolerance in laboratory and field condition. Seeds of forty eight cultivars of lentil were grown in plant growth chamber at 34°C with 70% relative humidity. Germination percentage was calculated. After one month survival percentage were evaluated. Germplasms were categorized according to their survival percentage as tolerant, moderately tolerant, susceptible and highly susceptible. Cell membrane thermostability test is a useful way to evaluate heat tolerance. Twenty five germplasms among the forty eight were taken to conduct the cell membrane thermostability test. Relative injury was calculated. All the germplasms were further evaluated in field condition in Baruipur Experimental farm & Udaynarayanpur. One field trial was conducted in the normal sowing condition and another in late sowing condition. Yield and survival data were recorded for all the germplasms. Considering the laboratory (including growth chamber study and cell membrane thermostability test) and field screening it was observed that Ranjan, Moitree, 14-4-1, IC 201710 and IC 208329 gave overall better performance in respect to heat tolerance.