Effect of dimming of global radiation on morphology and yield of wheat crop in Delhi

Abstract

Long-term observations of the surface global solar radiation in recent decades have shown a widespread declining trend in many parts of the world. Experient was carried out at the farm of ICARIndian Agricultural Research Institute, New Delhi during rabi season of 2014-15 and 2015-16 to study response of three cultivars (HD 2967, WR 544 and PBW 502) of wheat under five reduced solar radiationlevels (0, 20, 35, 50, 75% shading). Plant height, internode distance and leaf area index (LAI) were measured at different DAS throughout the crop growth period. The result shows that plant height and internode distance increased under 75% shading treatment. The highest leaf area index (LAI) was observed in 35% shading treatment, followed by 20% shading and control. Final biomass, grain yield and harvest index decreased significantly with shading and was lowest in 75% shading treatment. Among the cultivars, HD 2967 performed better under reduced radiation condition as compared to other cultivars.