Studies on Effect of Terminal Heat Stress on Seed Quality and its Mitigation in Chickpea (Cicer arietinum L.)

Abstract

A field experiment was conducted to know the effect of terminal heat stress on seed yield and its mitigation in chickpea was carried out during 2021-22 at Seed Unit, University of Agricultural Sciences, Raichur. High temperature during sowing time from early to late and very late directly affect the vegetative and anthesis stages and it was overcome by spraying the plants with heat stress mitigating chemicals. The experiment was laid out with three dates of sowing and ten foliar spray each treatment was replicated twice in a split plot design. Spraying was done at two stages of crop growth i.e., at vegetative (35-40 DAS) and anthesis stage (50-60 DAS) in all dates of sowing. The interaction between dates of sowing and heat stress mitigating chemicals showed highest physiological and seed quality parameters i.e. chlorophyll stability index (D3T3) (73.06 and 74.63%), minimum cell membrane injury index (55.09 and 63.63 %), maximum proline content (D3T3) (6.79 and 9.37 µ mol g-1), relative water content (83.79 and 75.10 %) at 60 DAS and at harvest, first count (90.50 %), final count (100.00 %), speed of germination (43.80), minimum time for radicle emergence (41.00 hrs), root length (17.32 cm), shoot length (10.12 cm), dry weight (27.10 mg), seedling vigour index-I (2643), seedling vigour index-II (2700). Among the treatments, sowing done at October 15th and plants sprayed with salicylic acid @ 400 ppm followed by gibberellic acid (100ppm) (T10) twice at vegetative and anthesis stage was found to be better in obtaining significantly higher physiological and seed quality parameters in chickpea variety JG-11 under heat stress conditions.