干旱胁迫对5种园林绿化植物生理生化的影响

Effects of drought stress on physiological and biochemical factors in five landscaping species

为给抗旱性较强的城市园林绿化植物的筛选提供依据,以5种园林绿化植物蛇莓、蛇莓萎陵菜、东北玉簪、紫萼玉簪和大萼铁线莲为试材,在持续干旱条件下,研究了园林绿化植物的渗透调节和抗氧化酶活性的响应特性。结果表明,持续15d干旱降低了土壤田间持水量,5种植物叶片水势和净光合速率随之下降。但是,蛇莓叶片水势和净光合速率降低的幅度比其它4种植物降低幅度小。干旱胁迫提高了叶片的丙二醛含量,细胞膜脂发生了过氧化。在持续15d干旱过程中,蛇莓和蛇莓萎陵菜叶片SOD活性增强。因此,蛇莓和蛇莓萎陵菜在干旱胁迫下能保持相对较高的光合速率,并利用酶促和非酶促系统清除氧自由基,表现出较强的抗旱能力。

In order to provide theoretical basis for screening of landscaping species with strong drought resistance, taking five landscaping species, Hosta. ensata F. Mackawa, Hosta ventricosa （Salisb.） Stearn, Potentilla centigrana, Duchesnea indica （Andr.） Focke and Clematis macropetala as test materials, osmotic adjustment and activities of antioxidant enzymes in leaves of the plants were studied. The results showed that field moisture capacity in soil was decreased, and water potential and net photosynthetic rate （Pn） were decreased after drought stress for 15 days. Water potential and net photosynthetic rate in leaves of D. indica （Andr.） Focke were declined slower than that of other four species. Malondialdehyde （MAD） contents in leaves of the five species were increased during drought stress for 15 days, which resulted in cell membrane-lipid peroxidation. Activities of SOD in leaves of D. indica （Andr.） Focke and P. centigrana were increased during drought stress for 15 days. In conclusion, D. indica （Andr.） Focke and P. centigrana showed stronger drought resistance, net photosynthetic rate in leaves of the two species maintained higher than that of the other three species under drought stress, and oxygen free radicals were cleaned by enzymatic system and non-enzymatic system.