Salinity tolerance in soybean is modulated by natural variation in GmSALT3

• Published in: The Plant journal : for cell and molecular biology Vol. 80; no. 6; pp. 937 - 950
• Main Authors: Guan, Rongxia, Qu, Yue, Guo, Yong, Yu, Lili, Liu, Ying, Jiang, Jinghan, Chen, Jiangang, Ren, Yulong, Liu, Guangyu, Tian, Lei, Jin, Longguo, Liu, Zhangxiong, Hong, Huilong, Chang, Ruzhen, Gilliham, Matthew, Qiu, Lijuan
• Format: Journal Article
• Language: English
• Published: England Blackwell Scientific Publishers and BIOS Scientific Publishers in association with the Society for Experimental Biology 01.12.2014; Blackwell Publishing Ltd
• Subjects: Alleles; Chromosome Mapping; chromosomes; CHX; CHX20; crops; Crops, Agricultural; cultivars; domestication; dominant genes; endoplasmic reticulum; exons; Fabaceae - cytology; Fabaceae - drug effects; Fabaceae - genetics; Fabaceae - physiology; Genes; Genes, Reporter; Genetic Variation; geographical distribution; Geography; Germination; Glycine max; Glycine max (L.) Merr; Glycine max - drug effects; Glycine max - genetics; Glycine max - physiology; Glycine soja; Glycine soja Sieb. et Zucc; haplotype; Haplotypes; ions; landraces; natural selection; natural variation; phloem; Phylogeny; Plant resistance; Plants, Genetically Modified; retrotransposons; saline soils; Salinity; Salt; salt exclusion; Salt Tolerance; Sequence Analysis, DNA; shoots; sodium; Sodium Chloride - pharmacology; Soybean Proteins - genetics; Soybean Proteins - metabolism; Soybeans; stress tolerance; xylem; CHX; CHX20; haplotype; Glycine max (L.) Merr; natural variation; salt tolerance; Glycine soja Sieb. et Zucc; salt exclusion; geographical distribution
• ISSN: 0960-7412; 1365-313X
• DOI: 10.1111/tpj.12695

The identification of genes that improve the salt tolerance of crops is essential for the effective utilization of saline soils for agriculture. Here, we use fine mapping in a soybean (Glycine max (L.) Merr.) population derived from the commercial cultivars Tiefeng 8 and 85–140 to identify GmSALT3 (salt tolerance‐associated gene on chromosome 3), a dominant gene associated with limiting the accumulation of sodium ions (Na⁺) in shoots and a substantial enhancement in salt tolerance in soybean. GmSALT3 encodes a protein from the cation/H⁺exchanger family that we localized to the endoplasmic reticulum and which is preferentially expressed in the salt‐tolerant parent Tiefeng 8 within root cells associated with phloem and xylem. We identified in the salt‐sensitive parent, 85–140, a 3.78‐kb copia retrotransposon insertion in exon 3 of Gmsalt3 that truncates the transcript. By sequencing 31 soybean landraces and 22 wild soybean (Glycine soja) a total of nine haplotypes including two salt‐tolerant haplotypes and seven salt‐sensitive haplotypes were identified. By analysing the distribution of haplotypes among 172 Chinese soybean landraces and 57 wild soybean we found that haplotype 1 (H1, found in Tiefeng 8) was strongly associated with salt tolerance and is likely to be the ancestral allele. Alleles H2–H6, H8 and H9, which do not confer salinity tolerance, were acquired more recently. H1, unlike other alleles, has a wide geographical range including saline areas, which indicates it is maintained when required but its potent stress tolerance can be lost during natural selection and domestication. GmSALT3 is a gene associated with salt tolerance with great potential for soybean improvement.