光照和水分处理下坡柳幼苗的生理响应

Physiological Response of Dodonaea viscosa Seedlings Treated with Light and Water

摘要:

为探讨坡柳(Dodonaea viscosa)在珊瑚砂环境的适应能力，设置全光、遮阴、黑暗3个光照处理，并采用梯度控水法设置正常控水、中度胁迫、重度胁迫3个水分梯度，对坡柳幼苗在光照和水分双因素处理下抗逆生理指标的变化进行了研究。结果表明，干旱胁迫和光照控制及其交互作用均对坡柳幼苗的丙二醛(MDA)、可溶性蛋白(SP)和脯氨酸(Pro)含量、超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性有显著影响(P<0.05)；遮阴和黑暗处理的MDA含量维持在较低水平; 黑暗条件下SOD活性随胁迫程度增加而升高；全光和正常控水下POD活性最高；随光照强度减弱，CAT活性逐渐升高; 遮阴和水分重度胁迫下SP含量最高，遮阴和水分中度胁迫Pro含量最高。因此，光照和水分对坡柳幼苗生长具有交互作用, 在特殊生境生态修复实践中，给予坡柳幼苗适当遮阴的同时应保证适当水分有利于幼苗生长。

Abstract:

In order to explore the adaptability of Dodonaea viscosa in coral sand environment, three light treatments, such as full light (FL), shade (HL) and dark (NL), and three water gradients, including normal water control (WW), moderate stress (MS) and severe stress (SS) were set up. The changes in physiological indexes of stress resistance of D. viscosa seedlings under both light and water treatment were studied. The results showed that light, water and their interaction had significant effects on contents of malondialdehyde (MDA), proline (PRO) and soluble protein (SP), and the activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) (P<0.05). The MDA content remaintained at a low level in HL and NL. SOD activity increased with the increase of dark degree. POD activity is the highest under FL×WW condition. With the decrease of light intensity, CAT activity increased gradually. The content of SP was the highest under HL and SS, and the content of Pro was the highest under HL and MS. Therefore, light and water had an interactive effects on the growth of D. viscosa seedlings. In the practice of ecological restoration in special habitats, appropriate shade and water would be helpful to the growth of D. viscosa seedlings.