Genetic diversity in Nepalese wheat cultivars based on agromorphological traits and coefficients of parentage

Abstract

Genetic diversity between parents is necessary to derive transgenic segregants from a cross. Coefficient of parentage (COP) and agromorphological traits (AMT) can be used to estimate diversity among cultivars. The pedigrees of 26 bread wheat cultivars were traced back to 77 ancestors and computed coefficient of parentage for all pair-wise combinations. All the cultivars used in the pedigree analysis were evaluated for six agromorphological traits in the National Wheat Research Programme (NWRP), Bhairahawa, Nepal in 1996. Six quantitative variables were used to compute dissimilarity distance matrix. Cluster and principal components analyses were performed on the matrix of COP and AMT values. COP matrix and the matrix based on agromorphological traits were compared. Mexico, India and Nepal were countries of the origin for 26 cultivars. A total of 77 ancestors originated from 22 different countries were used to develop these cultivars. Most of the ancestors were aestivum (80.52%) and spring growth habit (64.94%). Maximum dissimilarity was between RR 21 and Annapurna 3 and the most closely related pair was Rohini and BL 1022 based on the AMT. The mean of COP for all cultivars was 0.159 0.256. The highest COP was between Annapurna 3 and Annapurna 2. Other more closely related pairs based on COP were Kalyansona and Annapurna 2, Pasang Lhamu and Annapurna 3, UP 262