A field experiment was conducted at research area of Department of Agricultural Meteorology, CCS Haryana Agricultural University, Hisar, during the kharif season of 2013-14. The main plots treatments consisted of four date of sowing (2 nd week of April, 4 th week of April, 2 nd week of May and 1st week of June) and the sub-plots consisted of three cotton varieties (HD 123, H 1098 and RASI 134). In the 2nd week of April sown crop consumed highest thermal and radiation indices, and efficiently converted the thermal/radiant energy into biomass production. The transmitted photosynthetic ally active radiation was lowest in G1 followed by G2, G3 and G4. All growth parameters and yield attributes were found highest in 2nd week of April sown crop. Among cotton varieties, RASI 134 consumed highest heat units, heliothermal units and photo thermal units as compared to H 1098 and HD 123 under different growing environments. | Quantification of energy indices requirement of cotton varieties under different growing environments
