Effects of different concentrations of PEG simulated drought stress on seed germination of Chinese cabbage
In order to explore the effect of polyethylene glycol(PEG-6000)simulated drought stress on seed germination of Chinese cabbage,we analyzed the effects of 5%～25%PEG on seed germination and 5%～20%PEG on seedling growth,physiology and expression of drought resistance related genes.The results showed that the germination rate of Chinese cabbage seeds treated with 25%PEG was significantly lower than that of the control.The germination potential of Chinese cabbage seeds treated with 20%and 25%PEG was significantly lower than that of the control,and the germination start time and germination duration were significantly increased.The germination index of Chinese cabbage seeds decreased gradually with the increase of PEG concentration,and the germination index of Chinese cabbage seeds treated with 25%PEG was significantly lower than that of other treatments.The length of hypocotyls and radicles of Chinese cabbage sprouts increased first and then decreased with the increase of PEG concentration.The fresh weight and dry weight of sprouts decreased gradually with the increase of PEG concentration,and the fresh weight and dry weight of Chinese cabbage sprouts treated with 20%PEG were the lowest.The superoxide anion(O2-)content,proline(Pro)content,peroxidase(POD),superoxide dismutase(SOD)and catalase(CAT)activities of Chinese cabbage sprouts treated with 5%～20%PEG showed an upward trend;the relative expression of Delta-1-pyrroline-5-carboxylate Synthase(P5CS1)increased first and then decreased,and reached the maximum in 15%PEG treatment;the relative expression of Gretchen Hagen 3(GH3)showed a gradual downward trend,and 20%PEG stress was the lowest;The relative expression of stress-induced genes,basic leucine zipper(bZIP62)and Mitogen-activated Protein Kinase(MAPKKK18),showed an upward trend,and reached the highest under 20%PEG treatment.The results showed that Chinese cabbage could germinate normally under low concentration PEG stress,while high concentration PEG stress inhibited the germination.Chinese cabbage sprouts can respond to different degrees of drought stress by regulating their own growth,protecting enzyme system and drought stress related gene expression.The results provide a theoretical basis for the drought resistance mechanism of Chinese cabbage.
Chinese cabbageseedsdrought stressphysiologydrought resistance gene
NETL
NSTL
万方数据
