Diallel Analysis and Selection Parameters For Yield and Yield Contributing Traits in Bread Wheat (Triticum Aestivum L.)

Abstract

Thesis title: "Diallel analysis and selection parameters for yield and yield contributing traits in brea wheat (Triticum aestivum L.)" Degree awarding university: Sardar Vallabhbhai Patel University of Agriculture and Technology, Meerut. The present investigation entitled "Diallel analysis and selection parameters for yield and yield contributing traits in bread wheat (Triticum aestivum L.)" was undertaken to collect infonnation on genetic parameters for yield and its components from a ten parents diallel analysis in bread wheat. The experimental material was comprised of 10 diverse parents and their 45 F1s from a diallel mating system, excluding reciprocals.. All genotypes were evaluated. in a Randomized Complete Block Design in three replications at Crop · Research Centre (Chirodi block) of SVP University of Agriculture & Technology, Meerut (U.P.) during rabi2013-14. The data were re~orded on fifteen characters namely, Days to ear emergence, days to 50% flowering, days to maturity, plant height (em), peduncle length (em), spike length (em), spikeletes per spike, grains per spikes, number of tillers per plant, biological yield per plant (g), grain yield per plant (g), harvest index (%), gluten content (%), flag leaf area (cm2 ), 1000 grain weight (g). ANOVA for the experiment revealed highly significant difference among the genotypes (treatments)for the all characters except gluten content, indicated the presence of substantial genetic variability in the present set of material. Genetic components analysis and analysis of variance for both general and specific combining ability was indicated that both additive and non-additive gene ( dominace) action were involved in expression of most of the traits under study. This suggested that for exploiting both the additive and non- additive gene action, the material may be handed though pedigree method of breeding, reciprocal recurrent selection, biparental matting system or through heterosis breeding for the improvement of yield and components in wheat.In the estimated component of variance ~g was higher than the respective o'-s for seven traits. The value of ~s were higher than the ~g values for rest of the tmits indicated predominance of non-additive genetic variance. The ratio of ~g to ~s ( o'-gl~s) was found less than unity for peduncle length, flag leaf are8, number of tillers per plant, number of spikelets per spike, number of grains per spike, biological yield per plant, harvest index, 1 000-grain weight and grain yield per plant. The va~u~s of average degree of dominance ( ~s/~gt·s was more than unity for the 9 traits indicated the over dominance. The estimates of gca effects of the parental lines for different characters revealed that none of the parental Jines excelled in gca effects for all characters studied. However parent HD-2967, DBW-90, ' HD-2824, NW-5038 and HD-2733 showed significant gca effect with good per se performance for yield . and for 8-10 characters related to productivity. These parents may be involved in cross breeding program followed by pedigree method of selection for development of genotypes with higher grain yield in wheat. 1 On the basis specific combining ability (sea) effects and good per se performance crosses PBW-435 x DBW-90, HD-3095 x Raj-4246, MP-3336 x IID-3095, PBW-435 x Raj-4246 and PBW-435 x MP-3336 . ' also for 5-6 traits yield components traits, hence, these cross combination may be exploited through heterosis breeding to have good hybrids with high grain yield in wheat.High heritability narrow sense was observed for the traits viz. days to ear emergence, days to 50% flowering, days to maturity, plant height. Moderate genetic advance (> 10%) was observed for biological yield per plant, grain :yield per plant and flag leaf area.Grain yield showed highly significant and positive correlation with biological yield per plant, number of tillers per plant, grains per spike, spikelets per spike and spike length, while with peduncle length and flag leaf area positive and significant correlation were observed which indicated that by improving these traits yield could be improved. Path analysis at genotypic level reveled that, biological yield per plant had high order of direct positive effect on grain yield per plant followed by days to maturity, days to 50% flowering, number of tillers per plant, flag leaf area, gluten content, spikelets per spike, plant height and harvest index. At phenotypic level, biological yield per plant displayed high order of direct effect on grains yield per plant followed by harvest index, grain per spike, number of tillers per pl.ant, 1000 grain weight, gluten content, plant height, flag leaf area and days to ear emergence. Ten crosses viz, HD-3095 x Raj-4246, MP-3336 x HD-3095, PBW-435 x Raj-4246, PBW- 435 x HD-3095, MP-4010 x HD-3095, HD-2967 x Raj-4246, HD-3095 x HD-2733, PBW-435 x MP- 3336, HD-2967 x HD-3095, and MP-3336 x MP-4010 showed positive significant heterosis over better parent along for with good per se performance grain yield per phtnt, while HD-3095 x Raj-4246,PBW- 435 x DBW-90,MP-3336 x HD3095, HD-3095 x HD-2733 and DBW-90 x HD-2733 ~ese cross combinations, either alone or in combination, may be exploited through heterosis breeding for improvement in {vheat yield.