模拟干旱胁迫对巴东木莲种子萌发和芽苗生长的影响

巴东木莲原生种群天然更新差,林下鲜见更新幼苗或幼树.为探究其种子萌发和芽苗在生长期对干旱胁迫的耐受性,该文以巴东木莲种子为材料,采用不同质量浓度的聚乙二醇(PEG-6000)模拟干旱胁迫,分析干旱胁迫对其种子萌发、芽苗生长及其相关的生理生化指标的影响.结果表明:(1)不同质量浓度的PEG溶液对巴东木莲种子萌发和芽苗生长...

Effects of simulated drought stress on seed germination and seedling growth of Manglietia patungensis

Native communities of Manglietia patungensis are difficult to regenerate naturally, and seedlings or saplings are rarely found under the forest. To explore the tolerance of seed germination and the growth period of bud seedlings under drought stress, we used the seeds of M. patungensis with different mass concentrations of polyethylene glycol(PEG-6000)to analyze the effects of drought stress on seed germination, sprout growth and related physiological and biochemical indexes under different simulate drought treatments. The results were as follows:(1)The concentration of PEG solution had a significant impact on seed germination and sprout growth of M. patungensis(P <0.05). The germination and survival rate gradually decreased with the increase of PEG mass concentration. When the PEG mass concentration was more than 301 g·L^-1, seed germination was inhibited, and the germination time was significantly delayed.(2)The chlorophyll content of M. patungensis buds decreased gradually with the increase of the degree of drought stress; the content of soluble protein and the activity of superoxide dismutase(SOD)enzyme increased and then decreased; While the contents of proline(Pro), malondialdehyde(MDA)and the activities of peroxide(POD)and ascorbate perixide(APX)enzyme increased. In summary, the water demand for seed germination and bud growth of M. patungensis is obvious. Although it can adapt to a certain degree of drought stress through osmotic adjustment and increase protective enzyme activity, it is necessary to prevent drought damage in the breeding process. The research provides a theoretical basis for seed reproduction and regeneration of M. patungensis, and contributes to the population expansion.