Difference In Gene Sequence Polymorphis & Gene Expression Under Salt Stress Between Wild Type Barley And Salt-tolerance Barley [Hordeum Brevisubulatum (Trin.) Link]

The soil salinization is the most urgent problem for agriculture. It can influence most plants'normal growth. But we also find some plants can grow and breed for community under this extreme environment. Hordeum brevisubulatium (Trin.) link is a kind of perennial forage grass belonging to gramineous type barley genus, which salt-tolerance capacity is strong. The mechanism of adapting salinity environment made shortsubulate barley as an ideal plant for researching of anti-adversity.In order to know the salt-tolerance mechanism and utilize key salt-tolerance gene, this paper chose wild type and salt-tolerance type barley as material, analyzed the physiological response to NaHCO3 stress, determined the suitable concentration to deal with the plants. At the same time, we analyzed the difference of gene expression by RT-PCR and cDNA-AFLP technonlgies, then acquired the relative important genes by nested PCR. The results were as follows:Through physiological experiment to determine the suitable treeting concentration for the plants: 100mM.Using RT-PCR to compare DREB1 and CIPK gene that expressed differently between wild type and salt-tolerance type barley at different time. We chose a-tubulin as the internal parameters. The results showed that in the plants which treeting with alkaline salt, its DREB1 expressed highest after 6hrs, and while treeting with neutral salt, DREB1 expressed highest at 12hrs later. Anyway CIPK expressed highest after 24hrs. Alkaline condition has little influence on CIPK, but under NaHCO3 stress, the response of wild type and salt-tolerance type barley are consistent.Under alkaline salt stress, Wild type and salt-tolerance type Barley have obvious difference in phenotype. So this study analyzed sequence difference by the AFLP technology. The result shows the difference is 1% when stating 1400 sequences.Using nested-PCR obtained the gene sequence of CIPK,NHX3,DREB1 The experiment respectively cloned the cDNA sequence of CIPK,NHX3,DREB1 from the normal type and the anti type of barley. At the same time, BLAST aligned the sequence. Analyzed the difference between the two type found the proteins has no difference. So we can not deduced, transcription has correlation with anti-salt.Analyse the expression difference by cDNA-AFLP. The normal type and the anti type of barley displayed different expression profile. By BLAST aligning, we chose one TDF which is a relative gene about salt stress. Then we designed primers for the sequence amplification. The sequence of the gene is the same in both wild type and tolerance type. But the expression level has difference in the two tyoe barley. Therefore the next step we may prove the tolerance of the gene through transgenic technology.