Vegetos

Abstract

Drought and heat cause yield reduction in wheat when there is rise in temperature during reproductive phase. Present experiment was conducted from 2006–07 to 2009–10 to induce heat tolerance by osmoprotectants and ethylene inhibitor on wheat cultivars. Spray of osmoprotectants (KNO3 @ 1.0 & 2.0%, CaCl₂ @ 0.5 & 1.0%) and ethylene inhibitor (CoCl₂ @10 & 15 μgml⁻¹) was done from booting stage at weekly interval. The grain yield of 40.5, 36.1, 43.5, 35 q/ha in control in PBW 343 and a maximum grain yield of 47.4, 50.6, 51.9, and 40.3 q/ha was recorded when 1.0% KNO₃ was sprayed. Similarly, WH 542 produced an yield of 44.4, 46.8, 50.7, 46.9 q/ha where 1.0% KNO₃ was sprayed. Yield in controlled conditions was 32.4, 34.1, 38.6 and 37.1 q/ha. It was also observed that the yield was reduced in both the varieties during 2009–10 when maximum temperature was 2.8°C higher than normal. During 2009–10, the maximum grain yield (56.5q/ha) was obtained in the treatment where CoCl₂ was sprayed @ 15 μg ml⁻¹ in WH 542 followed by CaCl₂ @ 1.0% (48.7q/ha). In PBW 343, KNO3 @1.0% (40.3 q/ha) and 2.0% (40.4q/ha) gave maximum grain yield. It indicates that osmoprotectants and ethylene inhibitor can neutralize heat stress.