Abstract: ABA plays an important role in the process of drought resistance as a drought signal molecular, so it's necessary to investigate the mechanism of ABA synthesis and it's signal transduction. Under PEG stress, both the ABA and CaM contents and the time of the largest values apperance were measured using the roots and leaves of 2-leaf-old winter wheat seedlings treated with ABA, part-roots stress and pre-treated with exterior TFP for 24 h respectively. ABA and CaM contents of roots and leaves were all increased at different extend by PEG, the time of the largest ABA apperance in root was prior to that of the leaves, but CaM was late. And the time of the largest ABA content were not late to that of CaM either in roots or in leaves. The ABA and CaM contents both roots and leaves were all enhanced by exterior TFP and ABA, and CaM contents appeared rise continually. Compared to PEG stress, the time of the largest ABA appearance was similar. When subjected to part-roots stress, the ABA content of roots which were subjected to stress didn't be affected, but it was increased in the roots of non-stressed seedlings, and the time of the largest value were lagged for 6 h and 18 h in both sressed-roots and non-stressed roots respectively; the CaM contents were all increased in both part of roots and leaves too. Compared to control, the times of the largest CaM and ABA values in leaves were all lagged for 12 h. CaM may not participate in the process of ABA synthesis of root under PEG stress. The ABA regulated the CaM level after synthesis under PEG stress.

Key words: Winter wheat, Root, Osmotic stress, Abscisic acid, CaM

CLC Number: 

• S512.01