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

Abstract

Salinity stress is one of the most important environmental limiting factors in wheat (Triticum aestivum L.) production and developing new salt-tolerant varieties is extremely important. Identification of genes and mechanisms involved in salinity tolerance for molecular modification of this plant is essential In the present study, 186 F12 recombinant inbred lines (RIL) populations were evaluated to identify quantitative trait loci (QTLs) for phenotypic and biochemical characteristics in seedling stage under salt-stress conditions. In total, 21 main-effect QTLs were identified using composite interval mapping (CIM) analysis for antioxidant activity, total protein content and proline, 21 QTL including different traits were detected on 1A1, 4A, 1B, 2B1, 2B2,2B3,3B, 5B1, 6B1, 6B2, 1D and 2D. Candidate genes were identified within QTL regions and gene ontology (GO) enrichment analysis was performed. In total, 10976 candidate genes (CG) were grouped into 99 GO terms (including 59 GO terms involved in the biological process category). Gene prioritization led to the determination of 236 CG, which were involved in hydrogen peroxide catabolic، antioxidant activity، hydrogen peroxide metabolic process، reactive oxygen species metabolic process، metabolic process، catabolic process، monocarboxylic acid metabolic process، regulation of biological quality oxidative stress ، regulation of the biological process, etc. This approach may be proposed to identify new CGs whose corresponding QTL is responsible for complex traits.