IDENTIFICATION OF DROUGHT TOLERANT KABULI CHICKPEA LINES UNDER PEG INDUCED OSMOTIC STRESS AT SEEDLING STAGE

Abstract

Chickpea is one of the major food crops of rain fed regions of Pakistan, where drought poses a serious threat to productivity by adversely affecting growth, germination, and seedling development. To minimize the effects of drought in chickpea, polyethylene glycol (PEG 8000) concentrations as T2: -0.19 MPa (2%), and T3: -0.47 MPa (5%) along with the control treatment (T1) were used to screen sixty genotypes for drought tolerance by an in vitro method at BARI Chakwal Punjab. The experiment was arranged in a Completely Randomized Design (CRD) and structured as a two-factor factorial. Different seedling parameters showed negative effects with increasing PEG concentration while proline and glycine betaine levels were directly associated with the PEG- induced osmotic stress. At highest osmotic stress level (-0.47 MPa), the genotypes 13KCC112 and 12KCC72 showed 80% germination followed by GP-36, GP-65, and 13KCC126 with 75% germination. The genotypes 12KCC72 (0.276%) and 13KCC112 (0.273%) yielded the best dry matter followed by 13KCC126 (0.265%). 12KCC72 yielded a superior dry matter stress tolerance index (44.304), followed by 13KCC126 (44.102) and 13KCC112 (43.217). The highest proline content was accumulated in genotypes 13KCC112, GP-36 and GP-65 with 11.62 µmol/g in each, followed by 12KCC72 (11.54 µmol/g). The results revealed that the genotypes 13KCC112, 13KCC126, 12KCC72, GP-36 and GP65 were good as drought tolerant advanced genotypes at seedling stages based on germination percentage, root length, shoot length, root/shoot ratio, seedling length, seedling stress tolerance index, dry matter, dry matter stress tolerance index, seedling vigor index, proline and glycine betaine content. Future breeding initiatives may employ these drought tolerant breeding lines for line x tester analysis.