Genetic diversity, population structure and marker-trait associations for agronomic and grain traits in wild diploid wheat Triticum urartu

Xin Wang,Kehui Zhan,Wenlong Yang,Jiazhu Sun,Guangbin Luo,Yiwen Li,Aimin Zhang,Dongcheng Liu

doi:10.1186/s12870-017-1058-7

Abstract

BackgroundWild diploid wheat, Triticum urartu (T. urartu) is the progenitor of bread wheat, and understanding its genetic diversity and genome function will provide considerable reference for dissecting genomic information of common wheat.ResultsIn this study, we investigated the morphological and genetic diversity and population structure of 238 T. urartu accessions collected from different geographic regions. This collection had 19.37 alleles per SSR locus and its polymorphic information content (PIC) value was 0.76, and the PIC and Nei’s gene diversity (GD) of high-molecular-weight glutenin subunits (HMW-GSs) were 0.86 and 0.88, respectively. UPGMA clustering analysis indicated that the 238 T. urartu accessions could be classified into two subpopulations, of which Cluster I contained accessions from Eastern Mediterranean coast and those from Mesopotamia and Transcaucasia belonged to Cluster II. The wide range of genetic diversity along with the manageable number of accessions makes it one of the best collections for mining valuable genes based on marker-trait association. Significant associations were observed between simple sequence repeats (SSR) or HMW-GSs and six morphological traits: heading date (HD), plant height (PH), spike length (SPL), spikelet number per spike (SPLN), tiller angle (TA) and grain length (GL).ConclusionsOur data demonstrated that SSRs and HMW-GSs were useful markers for identification of beneficial genes controlling important traits in T. urartu, and subsequently for their conservation and future utilization, which may be useful for genetic improvement of the cultivated hexaploid wheat.

Highlights

Wild diploid wheat, Triticum urartu (T. urartu) is the progenitor of bread wheat, and understanding its genetic diversity and genome function will provide considerable reference for dissecting genomic information of common wheat
Plant material A total of 238 T. urartu accessions, which covered most of the original areas, were subjected to simple sequence repeats (SSR) and highmolecular-weight glutenin subunits (HMW-GS) analysis with SDS-PAGE
The data revealed a broad variation for all traits in these T. urartu accessions, e.g. plant height (PH) had an average of 112.43 cm with 12.23 cm standard deviation in E1, and thousand-grain weight (TGW) ranged from 4.29 to 18.87 g with 2.96 g standard deviation in E5

Summary

Introduction

Triticum urartu (T. urartu) is the progenitor of bread wheat, and understanding its genetic diversity and genome function will provide considerable reference for dissecting genomic information of common wheat. As a wild diploid progenitor of hexaploid wheat, T. urartu harbors rich allelic diversity for numerous important traits, including agronomic characteristics, grain quality and biotic stress tolerance [9,10,11]. Genetic variation of T. urartu has been investigated using various markers such as isozyme, restriction fragment length polymorphism (RFLP), amplified fragment length polymorphism (AFLP), and random amplified polymorphic DNA (RAPD) markers [12,13,14,15,16]. Such genetic diversities can be exploited to elucidate the genetic basis of natural variation of important quantitative traits. More accessions widespread should be employed to provide a more comprehensive on the characteristic of the whole population

Objectives

Methods

Results

Conclusion