Genetics of Physiological, Fiber and Yield Contributing Traits in Cotton Grown under Normal and Water Stress Conditions

Drought is the primary constraint to achieve the goal of sustainable crop production. Drought severely affects the production and fiber quality of cotton. To overcome this problem, development of drought resilient cotton cultiv ars with better lint quality and yield is a sustainable solution. Therefore, an experiment was conducted to evaluate the genetics of yield and quality traits of cotton under drought. Seventy cotton genotypes were screened against drought stress in glass house using completely randomized design based on cell membrane thermo stability (CMT), relative water contents, excise leaf water loss, fresh and dry shoot weight, fresh and dry root weight and root -shoot ratio. On basis of mean performance eight genotypes (05 lines and 03 testers) were selected. Selected lines and testers were crossed to obtain 15 Fl hybrids. Eight parents and 15 hybrids were sown in pots in glasshouse under two water levels i.e., normal and drought. Data regarding various physiological, yield and fiber quality parameters viz., CMT, FT WL, RWC, chlorophyll contents (CC), plant height (PH), number of monopodial branches per plant (NMBP), number of sympodial branches per plant (NSBP), number of bolls per plant (NBP), seed index (SI), fiber fineness (FF), fiber strength (FS) and staple length (SL) were collected. Degree of dominance revealed that all parameters were highly influenced by non-additive gene action under both water regimes except for NMBP under stress environment. Parental genotypes FH-682, 149-F and CIM-240, CRIS-134 were good general combiner for most of the studied traits under normal and drought conditions and could be used in a breeding programfor development of cotton variety. Due to non-additive types of gene action for mo st of the traits, it is suggested to delay selection for latter generations in developing drought tolerant high yielding genotypes. (C) 2020 Friends Science Publishers