Genetic variability for selective tolerance to imazethpyr in chickpea (Cicer arietinum L.)

Abstract

Herbicide tolerant varieties offer opportunity for timely control of weeds through need-based applications of herbicides. Post-emergence herbicides for weed control in chickpea could be efficiently used when the available cultivars are not sensitive to the given herbicide. In order to identify sources of herbicide tolerance for the commonly post emergence herbicide viz., imazethapyr, a study was undertaken involving thirty chickpea genotypes during winter 2015-16. Assessment of genotypes following herbicide application revealed large genetic variation for tolerance to imazethapyr. Herbicide tolerance scores (HTS) of genotypes ranged from 2.0 to 3.7 at 10 days after spray. At 30 days after spray, except JG 11 (2.3) all other genotypes recovered fully and recorded HTS of 2.0. But the overall decrease in grain yield due to imazethapyr was 18.5 % which ranged from 1.63% to 45% across genotypes. A few promising chickpea lines viz., ICCIL 01034, ICCV 09106, ICCIL 01026, ICCIL 01031, ST-3-D-2, NBeG 49, NBeG 3, NBeG 47 and JG 11 were identified with tolerant to moderately tolerant reaction to imazethapyr with less yield penalty. In both ‘control’ and ‘spray’ plots, high values of heritability and genetic advance were also recorded for shoot biomass, 100 seed weight, harvest index and grain yield.