Abstract
Arabidopsis thaliana has approximately 1000 accessions (ecotypes). Although there are few differences among their nucleotide sequence, these subtle differences induce genetic variation in phenotypes such as flowering time or stress tolerances. Recently, the 1001 Genome Project have started to discover the whole-genome sequence variation In Arabidopsis 1001 accessions. Taken together, these advances now make it possible to identify the genetic mechanisms underlying the adaptive evolution of complex traits.
We had isolated 4 salt tolerant Arabidopsis accessions from 354 accessions collected in RIKEN BRC. Interestingly, all of the salt tolerant accessions showed ABA hyper-sesitivity at the germination stage. It is known that the transgenic plants overexpressing an ABA responsive transcription factor, AREB1 shows the similar phenotype, suggesting that ABA signaling plays an important role in the salt tolerant mechanism among these accessions. We are investigating the relationship between the salt tolerance and the ABA sensitivity in salt tolerant accessions genetically.
