Studies On The Effects Of Endophytic Bacteria On The Mitigation Of Rice Seedlings Under Aluminum Stress

Aluminum ions in acidic soils can inhibit the growth of plants and affect the yield of crops.That the physiological toxicity of aluminum ions to crops alleviated is of great significance to increase the yield of crops.The endophytic fungus Gao Y1-1 was isolated from the leaves of Suaeda salsa.This endophytic fungus was used to infect the rice seedlings of Liaoxing 1.They were divided into infected group(E+)and non-infected group(E-),treated with different concentrations of albumin(0 ?M?40 ?M?80 ?M?120 ?M)at the same time.The plant height,root length,antioxidant enzyme activity and photosynthetic parameters were measured on the 9th day after Al3+ stress.The effects of Gao Y1-1 on the growth of rice seedlings were studied under Al3+ stress.The results were as follows:1.The plant height of rice seedling was higher than that of E-group.The dry weight and root dry weight of aboveground part were significantly higher than that of E-group.The root length was significantly lower than that of E-group,indicating that Gao Y1-1 of endophytic fungi could increase the biomass of rice seedlings.2.The contents of chlorophyll a,chlorophyll b and carotenoid in rice seedlings infected with Gao Y1-1 endophytic fungi were significantly higher than those in E-group,which indicated that Gao Y1-1 endophytic fungi could promote photosynthesis and accumulate organic matter after infecting rice seedlings.3.The activities of antioxidant enzymes such as POD and CAT in rice seedlings infected with endophytic fungi with Gao Y1-1 concentration were significantly higher than those in Egroup,but the production of reactive oxygen species O2-was significantly lower than that in Egroup,indicating that Gao Y1-1 endophytic fungi could enhance antioxidant enzyme activity in rice seedlings.Damage caused by aluminum stress reduced.4.The MDA content of rice seedlings infected with endophytic fungi with Gao Y1-1 was significantly lower than that of E-group,and the electrical conductivity was significantly lower than that of E-group,which indicated that Gao Y1-1 concentration of endophytic fungi contributed to the decrease of membrane lipid peroxidation under Al stress.The content of soluble sugar and soluble protein in rice seedlings infected with endophytic fungi with Gao Y1-1 was significantly higher than that in E-group.5.The activity of As A,GR and APX in rice seedlings infected with Gao Y1-1 endophytic fungi was significantly higher than that in E-group,but the content of GSSG in E-group was significantly lower than that in E-group.6.The content of sucrose and starch in rice seedlings infected with endophytic fungi with Gao Y1-1 was higher than that in E-group,which indicated that endophytic fungi with Gao Y1-1 could help rice seedlings accumulate more sugar.Invertase activity in the key enzymes of carbon cycle was significantly higher than that in E-group.The activity of SS and SPS was significantly lower than that of E-group.