碱蓬内生真菌对镉胁迫水稻幼苗生长及生理生化指标的影响

Effects of Endophyte Isolated from Suaeda salsa on Growth and Physiological and Biochemical Indexes of Rice Seedlings

为探明碱蓬内生真菌EF11-01菌株对重金属镉胁迫水稻幼苗生长及生理生化指标的影响,分别采用干重法、紫外分光光度法、氯化硝基四氮唑蓝法和愈创木酚法等测定其对镉胁迫水稻幼苗苗高、根长、地上部分干重和地下干重、叶绿素含量、超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)等抗氧化酶活性的影响。结果表明:在镉胁迫条件下,水稻幼苗的生长受到抑制,其抑制作用随镉胁迫浓度的增大而增强;EF11-01菌发酵液处理的水稻幼苗苗高、根长、地上部分干重和地下干重均比未加菌处理的增大;水稻幼苗叶绿素含量及抗氧化酶活性均高于未加菌的处理。碱蓬内生真菌EF11-01可以提高水稻对镉胁迫的抗性,促进生长,提高叶绿素含量,增强抗氧化防御能力。

To study the effects of endophyte fungus EF11-01isolated from S.salsa on rice seedling exposed to cadmium stress, plant growth parameters, chlorophyll content and antioxidant enzymes activities （SOD,POD and CAT）were determined by dry weight,ultraviolet spectrophotometry,nitroblue tetrazolium and guaiacol method.Results showed that under cadmium （Cd）stress,growth of non-infected EF11-01 rice seedling was significantly inhibited. It occurred in a dose-dependent manner, namely inhibition action increased with the increase of the Cd concentrations.Endophyte-infected seedlings had greater shoot length,root length,above-ground and below-ground dry weight compared to non-infected EF11-01 seedlings.Chlorophyll content and antioxidant enzymes activities （SOD,POD and CAT）were significantly higher in the endophyte infected rice seedlings than that of endophyte non-infected.These results suggested that endophytic fungus EF11-01 improved rice seedling growth under moderate Cd stress,which were reflected by more dry weight,Chlorophyll content and higher antioxidant enzyme activities.