Seed pretreatment and foliar application of potassium confers drought tolerance in green gram

Abstract

Laboratory and field studies were performed to evaluate the role of potassium as seed priming agent in combination with foliar supply for induction of drought tolerance in green gram. In the laboratory experiment, best priming treatment of potassium (2%) was selected when green gram was exposed to PEG induced drought (-2.0 MPa). Field experiment was carried out to test the performance of screened priming treatment along with sequential supply of potassium under normal irrigation and drought at 40 days after sowing. Drought significantly affected different agronomic and yield traits including plant height, branches plant−1, number of pods plant−1, grains per pod−1, 1000 grains weight, grain yield and biological yield. Seed priming improved different agronomic and yield related traits as compared to non-primed seed except number of grains per pod. Peak values of CGR (11.39 g m−2 day−1) during 45-55 DAS, LAI (2.75) at 45 DAS, Final NAR (17.39 g m−2 day−1), final LAD (86.65 Days), LWR (0.59) at 35 DAS, LAR (283.27 cm2 g−1) at 35 DAS were recorded under drought with hydropriming of seed along with 1% K sequential spray as compared to rest of treatment. Maximum branches per plant (10.33), pods per plant (46.67), grain yield (750.38 kg ha−1), biological yield (1923.54 kg ha−1), relative water contents (75.26%), chlorophyll contents (44.75) and membrane stability index (83.95%) were recorded in with seed hydropriming + 1% K sequential spray. Thus, seed hydropriming along with 1% K sequential spray can be opted to alleviate drought in green gram under field condition.