Study on growing degree days, heat use efficiency and weather indices of timely sown wheat (Triticum aestivum L.) varieties

Abstract

The field experiment was conducted during Rabi season of 2017-18 at Students’ Instructional Farm of Chandra Shekhar Azad University of Agriculture & Technology, Kanpur, UP (India) to assess the performance of timely sown wheat varieties in relation to climate change situation and to assess impact of maximum temperature, minimum temperature and growing degree days on wheat cultivars. The treatments consisted 10 wheat varieties viz., K307, K 402, K 607, K 1006, HD-2733, DBW-17, HD-2967, PBW-343, PBW-502 and PBW-550, laid out in Randomized Block Design replicated three times. The varieties were sown on 17th November, 2017 and harvested at physiological maturity ranged 130 days to 142 days after sowing. The inputs were given time to time at recommended rates. The meteorological data viz. minimum temperature maximum temperature at standard meterological weeks (SMW) were collected from meteorological observatory and growing degree days were calculated. The results exhibited that temperature (maximum and minimum) and growing degree days established positive correlation with growth characters, yield attributes and grain yield wheat varieties. Comparatively more duration (140 days) varieties viz. HD 2967 and PBW 343, recorded maximum growing degree days (1909.9), yielded maximum grain yield (5590.0 kg and 5277.00 Kg ha-1), better harvest index (42.23% and 39.90%), respectively. The minimum grain yield (4601.00 kg ha-1) and harvest index (35.67%) was recorded under PBW 502. The heat use efficiency of K402, HD 2967 and PBW-343 was found higher (3.05, 2.93 and 2.76 kg °C day-1, respectively) while, K307 recorded minimum (2.62 Kg °C day-1) HUE.