1. Loss of salt tolerance during tomato domestication conferred by variation in a Na + /K + transporter
- Author
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Qingfeng Niu, Yechun Hong, Jinjuan Bai, Jian-Kang Zhu, Huazhong Shi, Yingfang Zhu, Kai Hua, Guangtao Zhu, Sanwen Huang, Juanjuan Yao, Zhen Wang, and Yumei Li
- Subjects
Population ,Salt (chemistry) ,Biology ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,0302 clinical medicine ,Coding region ,education ,Domestication ,Molecular Biology ,Gene ,030304 developmental biology ,Genetics ,Molecular breeding ,chemistry.chemical_classification ,0303 health sciences ,education.field_of_study ,General Immunology and Microbiology ,General Neuroscience ,fungi ,food and beverages ,Transporter ,Articles ,chemistry ,030217 neurology & neurosurgery ,Homeostasis - Abstract
Domestication has resulted in reduced salt tolerance in tomato. To identify the genetic components causing this deficiency, we performed a genome‐wide association study (GWAS) for root Na(+)/K(+) ratio in a population consisting of 369 tomato accessions with large natural variations. The most significant variations associated with root Na(+)/K(+) ratio were identified within the gene SlHAK20 encoding a member of the clade IV HAK/KUP/KT transporters. We further found that SlHAK20 transports Na(+) and K(+) and regulates Na(+) and K(+) homeostasis under salt stress conditions. A variation in the coding sequence of SlHAK20 was found to be the causative variant associated with Na(+)/K(+) ratio and confer salt tolerance in tomato. Knockout mutations in tomato SlHAK20 and the rice homologous genes resulted in hypersensitivity to salt stress. Together, our study uncovered a previously unknown molecular mechanism of salt tolerance responsible for the deficiency in salt tolerance in cultivated tomato varieties. Our findings provide critical information for molecular breeding to improve salt tolerance in tomato and other crops.
- Published
- 2020