|Author:||Maharaj, Singh ; Chauhan, J. S. ; Meena, M. L.|
|Book Group Author:||NA|
Genotypic variation for water use efficiency (WUE) and leaf gas exchange parameters and their associations with seed yield and related attributes were investigated during rabi season 2007-08 under drought stress utilizing 18 advanced breeding lines/varieties of Indian mustard (Brassica juncea L.). Wide variation was observed for water use efficiency, photosynthetic rate and stomatal conductance. The heritability estimates varied from 61.7 (internal CO2 concentration) to 90.7% (stomatal conductance). Fairly high heritability estimates for stomatal conductance, WUE and photosynthesis rate were associated with moderate to high genetic advance implying predominant role of additive gene effects in the expression of these characters and suggesting effectiveness of selection. The relationship of WUE was significant and positive with seed yield/plant (r=0.539**) and other yield attributes studied except 1000-seed weight. Seed yield/plant was also positively and significantly associated with photosynthetic rate (r=0.828**), stomatal conductance (r=0.657**) and internal CO2 concentration (r=0.691**). The regression analysis of gas exchange parameters and seed yield suggested that photosynthetic rate, stomatal conductance and WUE accounted for 68.5, 43.2 and 29.0% of the variability in seed yield, respectively, under drought stress. Seven genotypes showing high WUE were identified for possible utilization in the breeding programme to improve productivity under drought stress.
|Pages:||361 - 366|
|Journal:||Indian Journal of Plant Physiology|
crop yield, drought, drought resistance, gas exchange,genetic effects, genetic variation, heritability, Indian mustard, leafconductance, leaves, photosynthesis, plant water relations, seeds,stomata, water stress, water use efficiency, yield components, Brassicajuncea, Brassica, Brassicaceae, Capparidales, dicotyledons, angiosperms,Spermatophyta, plants, eukaryotes, Capparales, carbon assimilation,carbon dioxide fixation, drought tolerance, genetic variability,genotypic variability, genotypic variation, heritable characters, FieldCrops (FF005) (New March 2000), Plant Breeding and Genetics (FF020),Plant Physiology and Biochemistry (FF060), Plant Water Relations(FF062), Plant Production (FF100), Environmental Tolerance of Plants(FF900)