A QTL located on chromosome 3D enhances the selenium concentration of wheat grain by improving phytoavailability and root structure

Dengcai Liu,Zhien Pu,Jirui Wang,Jian Ma,Yuming Wei,Ying Pei,Jian Yang,Youliang Zheng,Wei Li

doi:10.1007/s11104-017-3556-7

Abstract

Background and aimsAs an essential mineral element, selenium (Se) plays a critical role in human health. Given the low concentrations (<100 mg Se kg–1) of Se in staple crops, the identification of genetic resources with enriched Se, as well as the genes controlling Se concentration, is valuable for the marker-assisted selection of Se-rich varieties.MethodsWe determined the chromosomal quantitative trait (QTL) for Se concentration over two consecutive plant growth cycles using recombinant inbred lines (RILs) treated with two different concentrations of Se under both field-grown and hydroponic conditions.ResultsSeveral QTL for Se concentration were detected across the different treatments. Significant genotypic variation in the tissues of the RIL was found at Se-deficicencycondition. Notably, a QTL located on 3D (interval 214.00–218.00, Qse.sau-3D) affected root length and Se concentration in the leaves and grains, suggesting the existence of the same allele with distinctly different functions. However, the QTL for the agronomic traits measured (plant height, flowering time, and tillering number) and Se concentration were not found to be located on the same chromosomal regions, suggesting that marker-assisted selection for both traits is feasible. Se concentrations in the grains were primarily determined by the mineral transport efficiency of the lines, and the line with the highest Se concentration in the grains always possessed larger, more fibrous root systems. The concentrations of Se in the plant tissues were in the order of: root > stem > grain.ConclusionsThis is the first study to document a Se-rich synthetic wheat line, and root structure and Se grain concentration was strongly affected by QTL located on 3D.

Highlights

Humans require more than 22 essential mineral elements, all of which can be supplied by an appropriate diet (Broadley et al 2010)
The average heights of the treatment plants were approximately 4 cm greater than CK1, and the flowering period was earlier by about 3 d. This indicates that the Se treatment increased the height of the recombinant inbred line (RIL) and induced earliness
Three quantitative trait loci (QTL) located on 2D involved in the control of flowering time exhibited a fixed expression pattern regardless of Se treatment (Table 2)

Summary

Introduction

Humans require more than 22 essential mineral elements, all of which can be supplied by an appropriate diet (Broadley et al 2010). It is estimated that more than 15% of the human population suffers from Se deficiency due to the low concentrations of Se present in staple crops (White 2016a, b). The Se content of wheat is an important consideration in human health. It is for this reason that the biofortification of crops, including the application of mineral fertilizers and improvements to the ability of seeds to acquire mineral elements, is advocated as an immediate strategy to increase mineral concentrations in edible crops, and improve yields from infertile soils. As an essential mineral element, selenium (Se) plays a critical role in human health. Given the low concentrations (

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Conclusion