Genetic diversity of agro-morphological characters in Indian wheat varieties using GT biplot

Abstract

This study examined the extent of agro-morphological variations in Indian wheat varieties and graphically displayed the interrelationships among them at phenotypic level. 258 wheat varieties developed in last fifty years (1961-2010) for six different agro-climatic wheat sowing regions of India were characterized for Distinctness, Uniformity and Stability (DUS) using 20 agro-morphological characters. DUS descriptors such as waxiness on plant parts, plant height and growth habit were identified as prominent morphological determinants for genetic diversity in Indian wheat. Genetic variability among these varieties was assessed using GT biplot and ordination analysis. First two PC axes explained 36.9 % of the total multivariate variation during PCA. GT biplot grouped Indian varieties in four distinct groups for selected DUS traits majorly on the basis of waxiness on plant parts, plant height and growth habit. Patterns of descriptor states were found almost similar for six different agro-climatic regions. This suggested that selection criteria for high yielding genotypes led to selection of similar descriptors pattern for Indian wheat and is independent of external factors like climate and demography. This information on variability and correlations of DUS descriptors will be useful to evaluate germplasm at agro-morphological and to develop core collections of Indian wheat using highly variable DUS descriptors identified in this study.