Identification of genetic variability and diversity in selected wheat (Triticum aestivum L.) germplasm under three different dates of sowing

Abstract

Genetic diversity offers crucial platform for improving the plant characteristics. Its exploitation is necessary to tackle the environmental fluctuations and for the effective exploitation of genetic resources in breeding programmes. Although wheat is one of the most thoroughly studied crops in terms of genetic diversity but its yield potential can further be enhanced by studying and identifying the suitable gemplasm and utilizing them in crosses. In this study twenty genotypes of wheat germplasm were undertaken for identification of genetic variability and diversity for adaptation in NEPZ in three different dates of sowing. Observations were recorded on thirteen traits. All genotypes were evaluated for genetic variability and diversity by using Analysis of variance and D 2-Statistics. Analysis of variance revealed a significant difference among the genotypes for all the traits under study except for Normalized Difference Vegetation Index. The highest estimates of genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) were observed for no. of fertile spikes per plant (13.85) yield per plot (33.16) respectively. High heritability coupled with high genetic advance was observed for days to heading (0.67, 13.08) followed by plant height and biomass. Based on D 2-Statistics, 20 genotypes were grouped into seven clusters following Tocher method in which cluster I has maximum number of genotypes. The highest inter-cluster distance was found between cluster II and IV (21.19) followed by IV and VII (17.09). This suggests that genotypes included in these clusters possess wide genetic diversity. Highest cluster mean was found for biomass (692.50) followed by yield per plot and days to heading. On the basis of divergence and cluster mean it may be concluded that maximum heterosis and better transgressive segregants could be obtained in crosses among genotypes of cluster II, IV and VII in breeding programme for varietal improvement in wheat.