Agrometeorological indices and intercepted photosynthetically active radiation in cotton crop under different growing environments

摘要

The field experiment was conducted for agrometeorological indices of cotton crop under different growing environments with 3 cotton cultivars i.e. HS 6, RASI 134 and MRC 6304 and 2 dates of sowing viz., 30th April and 30th May at Research Farm, Department of Genetics and Plant Breeding CCSHAU Hisar at longitude of 75° 46 ' E and latitude of 29°10 1N during kharif 2011. The crop was grown under protected and unprotected conditions. Daily meteorological data was recorded at Agrometeorological Observatory which was used for computation of following agrometerological indices i.e. heat unit, heliothermal and photothermal unit. Intercepted photosynthetically active radiation was measured at different phenological stages. Cotton cultivar RASI 134 took significantly higher number of days at all phenological stages as compared to other cultivars viz., HS6 and MRC 6304. The values of thermal indices accumulated were higher under protected conditions in all the treatment combination than unprotected conditions. The heat unit, photothermal units and heliothermal units consumption was maximum in cotton sown in 30th and was minimum in 30th May sown crop. The more PAR value (26845 cal cm~2) was recorded in RASI 134 as compared to MRC 6304 (25387 cal cm~2) andHS 6 (24185 cal cm~2) under protected conditions. In case of unprotected conditions the highest PAR value was observed for cultivar RASI 134 (26611 cal cm~2) followed by MRC 6304 (24296 cal cm~(-2)) and HS 6 (22515 cal cm~2].