A proteomic study of the response to salinity and drought stress in an introgression strain of bread wheat.

The effect of drought and salinity stress on the seedlings of the somatic hybrid wheat cv. Shanrong No. 3 (SR3) and its parent bread wheat cv. Jinan 177 (JN177) was investigated using two-dimensional gel electrophoresis and mass spectrometry. Of a set of 93 (root) and 65 (leaf) differentially expressed proteins (DEPs), 34 (root) and six (leaf) DEPs were cultivar-specific. The remaining DEPs were salinity/drought stress-responsive but not cultivar-specific. Many of the DEPs were expressed under both drought and salinity stresses. The amounts of stress-responsive DEPs between SR3 and JN177 were almost equivalent, whereas only some of these DEPs were shared by the two cultivars. Overall, the number of salinity-responsive DEPs was greater than the number of drought-responsive DEPs. And most of the drought-responsive DEPs also responded to salinity. There are both similarities and differences in the responses of wheat to salinity and drought. A parallel transcriptomics analysis showed that the correlation between transcriptional and translational patterns of DEPs was poor. The enhanced drought/salinity tolerance of SR3 appears to be governed by a superior capacity for osmotic and ionic homeostasis, a more efficient removal of toxic by-products, and ultimately a better potential for growth recovery.