Abstract: Illumina RNAsequencing was performed in two alfalfa samples of control （WT_CK2） and NaCltreated samples（WT_N2）in order to estimate a broad spectrum of transcription factor genes affected by salt stress，and the realtime fluorescent qRTPCR technique was used to verify the expression characteristics of random selected 4 genes. These results indicated that 7 497 of them showed two fold higher or lower difference under NaCl stress from the control， including 474 transcription factors （TFs） belonging to 46 transcription family， among which 242 genes were upregulated and 232 were downregulated. Transcription factor families including bHLH，NAC，WRKY and C2H2， among which more than 70% genes were upregulated. Expression patterns of random selected 4 genes confirmed the results of the digital gene expression profile. In addition， this study also identified a large number of candidate functional transcription factor genes such as MsERF110， MsERF071， Ms bHLH36， MsZFP， MsHSFB3， MsMYB， MsNAC， MsWRKY and so on， which appeared to be constitutively involved in the response to salt stress. This study revealed that many transcription factor family were involved in response to salt stress in leaf of southern type alfalfa.

Key words: southern type alfalfa, transcription factor, leaf transcriptome, salt stress