Assessment of Genotypic Variability for Growth, Biophysical Parameters, Yield and Yield-Attributing Characters Under Drought Stress in Cotton

Abstract

Increasing scarcity of irrigational water is a major threat to sustainable production of cotton ( Gossypium hirsutum L.). Drought stress is a complex phenomenon affecting the physiology of cotton plant, in turn reducing crop growth, yield and yield components. An experiment was conducted using 20 Gossypium hirsutum genotypes grown in RBD design at Agricultural Research Station, University of Agricultural Sciences, Dharwad, Karnataka, and evaluated for genotypic variability for growth phenomena, biophysical parameters, yield and yield-attributing characters under irrigated and water-de fi cit condition. Under both irrigated and rainfed conditions, ARBH-813 recorded highest numbers of bolls per plant, while GSHV -97/612 recorded the least. Maximum boll weight was recorded by AKH-0205 followed by H-1452/10 and the least by NH-635 in irrigated condition. Under rainfed conditions, H-1452/10 recorded the highest boll weight. Under both irrigated and rainfed conditions, BS-30 and ARBH-813 recorded the highest water potential, while GJHV-358, GISV-218, H-1452/10 and HBB-101 recorded the least, and the genotype BS-279 recorded highest photosynthesis rate, while LRA-5166 recorded the least SPAD value. The genotypes BS-279, ARBH-813 and Sahana proved better as they recorded highest seed cotton yield under both conditions and least to moderate drought susceptibility indices. These are found to be desirable genotypes for drought situations.