Thermal Response of Spring–Summer-Grown Black Gram (Vigna mungo L. Hepper) in Indian Subtropics

The thermal environment of a crop is one the prime factors enhancing growth and production by regulating its physiological processes at different phenophases. To study impact regime on spring–summer-grown black gram (variety Pant Urd 31), an experiment was conducted with sowing dates (from first to third week March), soil application cobalt (Co) foliar sprays potassium (K) boron (B) in various combinations split–split plot design during 2020 2021. first-week-of-March-sown recorded more accumulated growing degree-days (GDD), photothermal units (PTU) heliothermal (HTU) longer duration than later sown crop. Higher daily mean temperature reproductive stage compelled it complete phenophases earlier normally crop, leading yield reduction. Soil Co 4 kg ha−1 K 1.25% B 0.2% mitigated adversities excess heat irrespective dates. Variations GDD HTU, respectively, explained variations about 75.8% 87.3% final dry matter accumulation 72.9% 84.8% seed through polynomial regressions respective years. maximum use efficiency (TUE) for biomass (0.24 g m−2/°C/day−1) (0.11 were observed combined due higher or lower