Evaluation of Salt Tolerance among 354 Arabidopsis thaliana Ecotypes, and the Mapping of a Gene Responsible for Salt Tolerance in A. thaliana Ll-1

Abstract

There are so many ecotypes (accession) of Arabidopsis thaliana. Although the difference in nucleotide level among them is around 1 bp for 1000 bp, it has revealed that they show various phenotypes in response to environmental stresses. In this study, to identify natural variability in salt stress tolerance, we compared the tolerance among 354 ecotypes collected in RIKEN BRC. Interestingly, most of A. thaliana ecotypes are more tolerant than the standard strain, Col-0, suggesting that Col-0 is a salt hyper-sensitive ecotype in A. thaliana. We obtained an ecotype, Ll-1, which shows salt tolerance clearly compared with Col-0. To identify the gene responsible for the salt tolerance in Ll-1, we are carrying out mapping. F1 population derived from a cross of Ll-1 to Col-0 shows high salinity tolerance as well as Ll-1. We mapped a salt tolerance gene of Ll-1 on the higher arm of chromosomes 4.