Physiological Responses of Wheat Associate with Heat Tolerance

Abstract

This study was performed to explore heat stress tolerance indices to judge terminal heat tolerance genotypes from nine wheat genotypes viz: AKAW 5023, AKAW 4927, PBN 4905, PBN 4751-02, NIAW 3523, NIAW 2891, AKAW 4210-6 (C), NIAW 34 (C), NIAW 1994 (C) at Wheat Research Unit, Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola (MH) during Rabi 2016-17 and 2017-2018. The trial was setup in RBD design with three replications. Yield and Physiological traits were recorded and correlated with yield. Genotype NIAW 2891 noted significantly high germination %,CTD (4.30oC), minimum membrane thermo-stability index (48.86%) at 75 DAS (grain filling stage), exhibited more RGR (0.0074 g g-1 day-1), NAR (0.0500 g dm2 day-1), early 50% flowering (58.16 days), days to maturity (91.83 days) and more grain yield ha-1 (35.65 q/ha) followed by genotype NIAW 3523 (33.83 q/ha) during both the year and noted as heat tolerance genotypes against the best check AKAW 4210-6. Correlation analysis showed that yield under stress environment had positive significant correlate with days to 50 % flowering and physiological maturity however, canopy temperature and membrane thermo-stability index had negative significant correlation with yield. Hence, due emphasis should be given to these attributes for genetic improvement in wheat under heat stress condition.