丛枝菌根真菌对盐胁迫下园林植物再力花 生长发育和光合特性的影响

Effects of Arbuscular Mycorrhizal Fungi on Growth and Photosynthetic Characteristics of Ornamental Plant Thalia dealbata under Salt Stress

为提高园林湿地水生植物的耐盐性,本试验以再力花为材料,研究接种丛枝菌根真菌(arbuscular mycorrhizal fungi,AMF)对NaCl胁迫下植株生长发育、根系活力、渗透调节物质、抗氧化酶活性及叶片光合特性的影响.结果表明,接菌+盐胁迫组(T1)再力花的盐害指数显著低于不接菌+盐胁迫组(N-CK),且T1组根系活力、株高、茎粗、地上地下干物质量均显著高于N-CK;与N-CK相比,施加AMF(T1)显著提高可溶性蛋白含量,降低可溶性糖和脯氨酸含量,同时还显著降低丙二醛含量,显著提高抗氧化酶(SOD、CAT、POD)活性;随盐胁迫时间延长,AMF处理(T1)叶片净光合速率、气孔导度、蒸腾速率及胞间CO_(2)浓度均呈现上升趋势,N-CK组则均呈下降趋势.综之,施加AMF可以有效缓解NaCl对再力花的渗透胁迫和氧化损伤作用,增强其对盐胁迫的抗性,从而促进植株生长和提高光合作用效率.

To improve the salt tolerance of aquatic plant in garden wetlands,the experiment was carried out with Thalia dealbata as material to study the effects of inoculation of arbuscular mycorrhizal fungi(AMF)on its plant growth and development,root activity,osmotic regulation substances,antioxidant enzyme activity and leaf photosynthetic characteristics under NaCl stress.The results showed that the salt damage index of T1 group(inoculating AMF under salt stress)was significantly lower compared with the N-CK group(non-inocu-lation of AMF under salt stress),while the root activity,plant height,stem diameter,aboveground and under-ground dry matter amount were significantly higher than those of the N-CK group.Compared with N-CK group,the inoculation of AMF significantly increased the content of soluble protein,reduced the content of soluble sugar and proline,and also significantly reduced the content of malondialdehyde,significantly increased the activities of antioxidant enzymes(SOD,CAT,POD).As the time increase of salt stress,the net photosynthet-ic rate(Pn),stomatal conductance(Gs),transpiration rate(Tr)and intercellular CO_(2) concentration(Ci)of the leaves treated with AMF showed upward trends,while those of N-CK group showed downward trends.Therefore,inoculation of AMF could effectively alleviate the osmotic stress and oxidative damage of NaCl to Thalia dealbata,enhance its resistance to salt stress,so as to promote the plant growth and increase the photo-synthetic efficiency.