Estimation of spatial genetic structure in inter-regional populations of Trigonella foenum-graceum L. species through phenotypic variation and seed protein profiling

Abstract

Fenugreek (Trigonella foenum-graceum L.) is an important legume crop mainly grown for its pharmacological and nutritional value in Mediterranean region, western Asia, Indian sub-continent and Africa. We evaluated 110 fenugreek accessions from diverse agro-ecological regions i.e. South Asia, Mediterranean, Middle East, Europe and Africa for phenotypic divergence and seed protein based variation. Significant agro-morphological variability was revealed by germplasm viz-a'-viz traits e.g days to flower initiation, days to flower completion, yield plant-1, plant habit, vigor, flower colour and plant height. Multivariate approach of Principal Component Analysis and Euclidean distance generated dendrogram distributed all accessions into 6 and 9 distinct groups for morpho-agronomic dissimilarities, respectively. Four principal components (PCs) with Eigen value higher than unity (E > 1), represented 65% variability in germplasm. Geographical distribution was evident by scatter plot as germplasm figured in 6 different sub-populations. Iranian accessions were most diverse, showing up in all sub-populations followed by Indian, Turkish, Ethiopian, Pakistani and Egyptian accessions which ranked in 5,4,4,3 and 3 sub-populations, respectively. Electrophoretic pattern of seed protein also exhibited considerable polymorphism in the range of 30~100 kDa. Maximum of 16 bands were produced in Turkish PI171872 and Indian PI175321 genotypes. UPGMA based cluster analysis distributed all accessions in 5 groups where accessions from close geographical proximity settled adjacently.