The Seeds And Seedlings Of Four Provenances Of Ziziphus Jujuba Var. Spinosa Responsed To Drought Stress

By using PEG-6000 to simulate drought stress and doing the seed ger mination experiment for the four provenances of Zizyphus Jujuba seeds from Yantai,Shijiazhuang,Yinchuan and Turpan,the precent study was carried out to research the response to drought stress on seed germination and vigor of four provenances of Zizyphus Jujuba seeds; By controlling the potting water and doing the drought-resistance experiment for the four provenances of Zizyphus Jujuba seedlings,the study was carried out to research the response to drought stress on the root morphology,chlorophyll fluorescence and physio-Biochemicai of four provenances of Zizyphus Jujuba seeds, to explore the law of the four provenances of Zizyphus Jujuba seeds and seedlings to drought stress and the drought resistance mechanism. The main results are as follows: 1. The larger the PEG-6000 concentrations was,the more severely the seed ger mination and seedling vigor of Zizyphus Jujuba seeds. With the increase of PEG-6000 concentrations, the four provenances of Zizyphus Jujuba seeds ' ger mination rate, germination index, stress index, seedling vigor index,radicle length,fresh weight,radicle activity,radicle volume, radicle surface, average radicle diameter were drecreased and different provenances of Zizyphus Jujuba seeds had different response for that; When the PEG-6000 concentrations was 20%, the seeds could not germinate, but they could recover ger minate after rehydration and had no differences with the control group. 2. With the drought stress aggravated, the four provenances of Zizyphus Jujuba seedlings' root length, root volume,root surface, root diameter, root activity, root-top ratio were increased in early and drecreased in later, and different provenances of Zizyphus Jujuba seedlings had different response for that. 3. With the drought stress aggravated, the four provenances of Zizyphus Jujuba seedlings' Fo, q N were increased gradually, and Fm, Fv/Fm, Fv/Fo, Yield, q P, ETR were drecreased gradually, but different provenances of Zizyphus Jujuba seedlings had different response for that. 4. With the drought stress aggravated, the four provenances of Zizyphus Jujuba seedlings' activity of SOD,POD,CAT were increased in early and drecreased in later, and different provenances of Zizyphus Jujuba seedlings had different response for that.The Zizyphus Jujuba seedlings of Yantai of the activity of SOD, POD, CAT reach the maximum in moderate drought and the growth range is small.The Zizyphus Jujuba seedlings of Shijiazhuang, Yinchuan, Turpan of the activity of SOD, POD, CAT reach the maximum in severe drought and the growth range is big. 5. With the drought stress aggravated, the four provenances of Zizyphus Jujuba seedlings' content of As A were increased gradually,and different provenances of Zizyphus Jujuba seedlings had different response for that.The growing rate of Zizyphus Jujuba seedlings' content of As A increases in tur n from Yantai to Turpan. 6. With the drought stress aggravated, the four provenances of Zizyphus Jujuba seedlings' content of PRO and SS were increased gradually,the content of SP were increased in early and drecreased in later, and different provenances of Zizyphus Jujuba seedlings had different response for that. The growing rate of Zizyphus Jujuba seedlings' content of PRO, SS, SP increases in tur n from Yantai to Turpan. 7. With the drought stress aggravated, the four provenances of Zizyphus Jujuba seedlings' content of chlorophyll, chlorophyll-a, chlorophyll-b were increased gradually,the value of chlorophyll a / b were increased in early and drecreased in later, and different provenances of Zizyphus Jujuba seedlings had different response for that. The decrease rate of Zizyphus Jujuba seedlings' content of chlorophyll, chlorophyll-a, chlorophyll-b, the value of chlorophyll a / b decreases in tur n from Yantai to Turpan. 8. With the drought stress aggravated, the four provenances of Zizyphus Jujuba seedlings' activity of NR were increased gradually, and different provenances of Zizyphus Jujuba seedlings had different response for that. The growing rate of Zizyphus Jujuba seedlings' activity of NR increases in tur n from Yantai to Turpan. 9. With the drought stress aggravated, the four provenances of Zizyphus Jujuba seedlings' content of MDA and superoxide, the relative conductivity were increased gradually, and different provenances of Zizyphus Jujuba seedlings had different response for that. The growing rate of Zizyphus Jujuba seedlings' content of MDA and superoxide, the relative conductivity decreases in turn from Yantai to Turpan. 10. Using the projection pursuit model to evaluate the four provenances of Zizyphus Jujuba seeds ' seed ger mination rate,ger mination index and so on, we can lear n that stress index, radicle length,seedling vigor index more deeply response to drought stess, and four provenances of Zizyphus Jujuba seeds ' drought resistance was Yantai<Shijiazhuang<Yinchuan<Turpan. Using the comprehensive evaluation value of the four provenances of Zizyphus Jujuba seedlings' root length,root surface,and so on, we can lear n that the four provenances of Zizyphus Jujuba seedlings' drought resistance was Yantai < Shijiazhuang < Yinchuan <Turpan.So we can draw a conclusion that Zizyphus Jujuba seeds' drought resistance evaluation are agreement with Zizyphus Jujuba seedlings' drought resistance evaluation.