Phenotypic and molecular diversity of wheat species (Triticum spp.) in relation to plant height and heading time

摘要

Plant height and heading time are important agronomic traits that significantly contribute to the improvement of wheat adaptability and yield. The aim of this study was to evaluate the level of phenotypic variability of these two traits in a collection of wheat species originating from 20 countries, to analyse its molecular diversity based on the microsatellite loci associated with the previously mapped quantitative trait loci, and to estimate potential of microsatellites to detect polymorphism in different wheat species and reveal allelic patterns in relation to the geographical origin. The significant differences in plant height and heading time among different wheat groups were observed, while the differences in means among three different growing seasons were significant only for heading time. The principal coordinate analysis distinguished wheat genotypes by their origin and ploidy level. Wheat varieties from America, South and Southeast Europe, and West and Central Europe had the highest molecular diversity, as was evidenced by the higher number of alleles, number of group-specific alleles, Shannon's information index and gene diversity. The Nei’s genetic identity indicated genetic similarity of geographically distinct groups, such as South and Southeast Europe and Russian (0.901) and South and Southeast Europe and American genotypes (0.638). The studied collection with high observed level of both phenotypic and molecular diversity for plant height and heading time may be a valuable source of variation for wheat breeders to fine adjust these traits to achieve better agronomic performance in certain local environments.