Studies on Genetic divergence and Interrelationship in Bread wheat (Triticum aestivum L.)

Abstract

T~e ~re~ent investigation entitled, "Studies on genetic divergence and mterrelat1onsh1p In bread wh~at (Triticum aestivum L.)" involving so elite lines/genotypes was undertaken to study the genet1c variability, heritability genetic advance correlation coefficient path coefficient analysis and genetic divergence. Fifty g~notypes were tested in randomized block design with .3 replications. The characters under study were days to SO% flowering, plant height, number of t1llers per plant, days to maturity, spike length, number of grains per spike, number of spike lets per spike, 1 000-grain weight, biological yield per plant, harvest index, gluten content and grain yield per plant. The analysis of valiance revealed significant differences among the genotypes for all the characters studied. High estimates of genotypic coefficients of variability were observed for biological yield per plant, followed by number of grain per spike and grain yield per plant; moderate GCV (%) was observed for plant height, followed by number of spikelets per spike and gluten content; low GCV (%)was observed for number of tillers per plant followed by length of spike, harvest index, days to maturity and days to SO% flowering. The heritability estimates varied from 59.40% to 99.60%. Very high estimates of heritability were found for the characters like grain yield per plant, biological yield per, number of spikelets per spike, plant height, number of grains per spike, spike length, number of tillers per plant, gluten content and harvest index. Highest genetic advance in percent of mean was observed for number of tiller per plant followed by grain yield per plant. The grain yield per plant had positive and significant association with. plant height, number of tillers per plant, length of spike, number of spikelets per spike, biological yield per plant and harve~t index both at genotyp~c and ph~noty~ic levels. Number of spikelets per spike had the highest d1rect effect an~ gen.otyplc correlatiOn. w1th grain yield followed by harvest index. The 50 genotypes ~ere g~uped mto m~e clusters. The mtracluster distance ranged from 2.042 to 2. 788. The max~ mum mter-cluster d1stance w~s betwee~ cluster 1 and VIII, suggesting the hybridization possibilities be!Ween. the. genotypes by .v1rtue ~f t~e1r wide genetic diversity. consequent upon the pres~nt mvest1gat1on on genet1c vanab1hty, heritability, genetic advance, correlation and path ~naly~1s ~~gge~ed that the geno~ypes t~~en .tor the present study were having high range of genet1c vanab1~1ty wh1ch rna~ be used m hybnd1zat1on programme for obtaining superior and desired gene recomb1~ants f~r part1~ular chara~er. ~oth the direct and indirect selection parameters were found potential. for 1mprov1ng the ~ra1t~ of 1ntere~ through selection breeding programme. on the basis of stud1es made on genetic d1v~rgenc~, 1t was suggested that the crosses between the genotypes of cluster I, and VIII may g1ve fruitful results in hybridization programme.