钙胁迫对黑骨藤种子萌发及幼苗生长的影响

Effects of Calcium Stress on Seed Germination and Seedling Growth of Periploca forrestii Schltr.

为了探讨CaCl_(2)胁迫对黑骨藤种子萌发和幼苗生长的影响,采用不同浓度梯度的CaCl_(2)溶液对黑骨藤种子和幼苗进行胁迫实验,分析不同浓度钙胁迫环境下的种子相关萌发指标和种子萌发后的幼苗生长指标,比较不同浓度钙胁迫环境下种子萌发特性的差异,以及钙胁迫对黑骨藤幼苗生长及生理指标变化的影响。结果表明,低浓度钙胁迫处理能促进黑骨藤种子的萌发,而高钙处理则抑制黑骨藤种子萌发,其发芽势、萌发率、发芽指数、逐日萌发率和生长指标随钙浓度的升高而下降,高钙环境对黑骨藤种子的萌发有抑制作用。随着钙胁迫浓度的增大,黑骨藤幼苗表观性状(侧枝数量、株高)生长逐渐受到抑制,其叶绿素含量随之降低,高浓度的钙胁迫会抑制黑骨藤幼苗的生长及叶片的光合作用;黑骨藤幼苗中可溶性糖含量随钙浓度的增加而呈逐渐升高的趋势,同时过氧化物酶、超氧化物歧化酶、谷丙转氨酶和谷草转氨酶活性随之逐渐升高,表明黑骨藤幼苗在钙胁迫环境下受到了渗透胁迫及黑骨藤幼苗在生长过程中主要依靠抗氧化酶系统来清除氧自由基,通过转氨作用进行代谢反应。综合分析表明,钙离子浓度过高会抑制黑骨藤种子的萌发和幼苗的生长,因此,在今后进行黑骨藤引种驯化过程中应适当控制钙离子浓度。

In order to investigate the effects of CaCl_(2)stress on seed germination and seedling growth of Periploca forrestii Schltr.,stress experiments were carried out on seeds and seedlings of Periploca forrestii Schltr.with different concentration gradients of CaCl_(2)solution,and seed-related germination indexes and seedling growth indexes after seed germination were analyzed under different concentrations of calcium stress.To compare the difference of seed germination characteristics under different concentrations of calcium stress,and the effects of calcium stress on the growth and physiological indexes of Periploca forrestii Schltr.seedlings.The results showed that low concentration calcium stress treatment could promote seed germination,while high calcium treatment inhibited seed germination.The germination potential,germination rate,germination index,daily germination rate and growth index decreased with the increase of calcium concentration.High calcium environment inhibited seed germination.With the increase of calcium stress concentration,the growth of the apparent traits(number of lateral branches,plant height)of the seedlings was gradually inhibited,and the chlorophyll content of the seedlings decreased.High concentration of calcium stress inhibited the growth of the seedlings and the photosynthesis of the leaves.The content of soluble sugar in the seedlings increased gradually with the increase of calcium concentration,while the activities of peroxidase,superoxide dismutase,glutamic-pyruvic transaminase and glutamic-oxalacetic transaminase increased gradually,indicating that the seedlings were subjected to osmotic stress under calcium stress,and the seedlings mainly depended on the antioxidant oxidase system to remove oxygen free radicals during the growth process.Metabolic reaction by transamination.The comprehensive analysis showed that high calcium concentration could inhibit seed germination and seedling growth of Periploca forrestii Schltr..Therefore,calcium concentration should be properly controlled in the future introduction and domestication process.