QTLs for seedling traits under salinity stress in hexaploid wheat

Abstract

Soil salinity limits agricultural production and is a major obstacle for increasing crop yield. Common wheat is one of the most important crops with allohexaploid characteristic and a highly complex genome. QTL mapping is a useful way to identify genes for quantitative traits such as salinity tolerance in hexaploid wheat. In the present study, a hydroponic trial was carried out to identify quantitative trait loci (QTLs) associated with salinity tolerance of wheat under 150mM NaCl concentration using a recombinant inbred line population (Xiaoyan 54×Jing 411). Values of wheat seedling traits including maximum root length (MRL), root dry weight (RDW), shoot dry weight (SDW), total dry weight (TDW) and the ratio of TDW of wheat plants between salt stress and control (TDWR) were evaluated or calculated. A total of 19QTLs for five traits were detected through composite interval mapping method by using QTL Cartographer version 2.5 under normal and salt stress conditions. These QTLs distributed on 12 chromosomes explained the percentage of phenotypic variation by individual QTL varying from 7.9% to 19.0%. Among them, 11 and six QTLs were detected under normal and salt stress conditions, respectively and two QTLs were detected for TDWR. Some salt tolerance related loci may be pleiotropic. Chromosome 1A, 3A and 7A may harbor crucial candidate genes associated with wheat salt tolerance. Our results would be helpful for the marker assisted selection to breed wheat varieties with improved salt tolerance.

Identification of Candidate Genes in QTL Regions for Biochemical Traits Underlying salt Response in bread wheat (Triticum aestivum) at the Seedling Stage

“…A genetic analysis on wheat's response to salinity stress was performed on a population of 114 inbred lines, where out of the 47 QTLs that were present on all wheat chromosomes, ten were detected at the germination stage and 37 were present on the seedling on all chromosomes except D7, D5, B4, D1, and B1 (Ma et al 2007). A study was conducted to identify the QTLs associated with wheat's salinity resistance by examining 19 seedlingstage QTLs, out of which 11 QTLs were associated with non-stress and six were associated with salinity (Ren et al 2018). Overall, environmental stresses lead to the decline or accumulation of essential metabolites, changes in protein synthesis and enzyme activity, and new protein production (Zhu, 2016) aimed at dealing with environmental stress in various ways (Kiani et al 2020).…”

Bulked Segregant Analysis‐Sequencing identification of candidate genes for salt tolerance at the seedling stage of sorghum (Sorghum bicolor)

“…In wheat, Hussain et al (2017) localized QTLs related to 22 salt tolerance‐related traits, and a total of 49 related QTLs were detected and distributed on 12 chromosomes. Ren et al (2018) detected a total of 19 QTLs associated with salt tolerance in the RIL population produced from lines Xiaoyan 54 and Jing 411, with QTLs' contribution rates ranging from 7.90% to 19.00%. With rapid developments in molecular biology and continuous improvements in plant whole‐genome sequencing, progress has been made in the genetic research of salt tolerance in other crops, which provides more informational resources to facilitate studies on the salt tolerance mechanism of sorghum.…”

Knock-down the expression of TaH2B-7D using virus-induced gene silencing reduces wheat drought tolerance

“…Sixteen days after the inoculation (about 44% FC under DS conditions), the leaves of each pot were collected for measurement of proline and MDA content, RWC and rate of relative electrolyte leakage. In the meanwhile, another trial comprising low nitrogen treatment (LN), salt stress treatment (SS) and non-stressed control were carried out according to previous literatures [ 40 , 41 ].…”