Morphological diversity and genetic variability of wheat (Triticum aestivum L.) genotypes in the southern hills zone

Abstract

The morphological diversity and genetic variability for 26 best-performing genotypes representing a spectrum of wheat varieties notified for different ecological zones of India were studied. The study aims to understand the relationship and contribution of quantitative characters and the genetic variation among the genotypes chosen. The field experiment was conducted in augmented randomized complete block design at ICAR-Indian Agricultural Research Institute (IARI), Regional Station, Wellington, The Nilgiris, Tamil Nadu, India. The correlation between flag leaf width (0.36), flag leaf area (0.38), and single plant yield (0.67) is positive and significant with the harvest index. Path coefficient analysis revealed the highest magnitude of direct positive effect on harvest index is through single plant yield (1.39), flag leaf area (1.03), and flag leaf width (0.77). The variability studies indicated that the traits flag leaf length, flag leaf width, flag leaf area, peduncle length, awn length, number of tillers per hill, single plant weight, single plant yield, and harvest index had high heritability and high genetic advance. The narrow difference between the values of GCV and PCV observed for all the characters under study suggested very low environmental influences upon them. The 26 genotypes were grouped into 7 clusters, each cluster represented a mix of genotypes notified for different ecological zones. This confirms the diversity among the genotypes irrespective of their notified ecological zones. The principal component analysis confirmed the correlations between the characters as obtained in correlation analysis highlighting the importance of flag leaf width, flag leaf area, and single plant yield. The above-mentioned three traits can be used as evaluating criteria for genotypes to be chosen in breeding programs in the southern hills zone.