Abstract: This study was aimed to investigate the effects of endophytic fungi on Photosynthetic performance and physiological characteristics of Hordeum bogdanii under alkali stress.Hordeum bogdanii with endophytic fungi (E+) and without endophytic fungi (E-) were used as experimental materials,and the Hordeum bogdanii plants were treated with a mixed alkali solution of 0,50,100,150,200 mmol·L^-1 for 21 days to analyze the changes of photosynthetic characteristics and physicochemical indexes.The results showed that with the increase of alkali concentration,net photosynthetic rate,stomatal conductance,transpiration rate,intercellular CO₂ concentration,chlorophyll a,b,carotenoid content,and antioxidant enzyme activity all showed a decreasing trend,while osmotic adjustment substances,leaf relative conductivity,and MDA content showed an increasing trend.At the same time,the net photosynthetic rate,stomatal conductance,transpiration rate,intercellular CO₂ concentration,chlorophyll a,b,carotenoids,proline,soluble sugar,and soluble protein content,and antioxidant enzyme activity of E+ were significantly higher than E-,MDA content and leaf relative conductivity were significantly lower than E-.It is concluded that endophytic fungi can significantly improve photosynthesis and physiological tolerance of Hordeum bogdanii plants under alkali stress,this Hordeum bogdanii endophytic fungus has a potential role in developing new strain alkali-tolerant.

Key words: Endophytic fungi, Hordeum bogdanii, Alkali stress, Physiological characteristics, Photosynthetic performance

摘要： 为了探究碱胁迫下内生真菌对布顿大麦(Hordeum bogdanii)光合性能和生理特性的影响。以带内生真菌(E+)和不带内生真菌(E-)布顿大麦为试验材料，用0，50，100，150，200 mmol·L^-1的混合碱溶液处理布顿大麦植株21天，分析其光合特征和理化指标的变化。结果表明：随着碱浓度的增加净光合速率、气孔导度、蒸腾速率、胞间CO₂浓度、叶绿素a，b、类胡萝卜素含量、抗氧化酶活性均呈现出降低趋势；渗透调节物质、叶片相对电导率、丙二醛含量呈现升高趋势。同时，E+的净光合速率、气孔导度、蒸腾速率、胞间CO₂浓度、叶绿素a，b、类胡萝卜素、脯氨酸、可溶性糖和可溶性蛋白含量，以及抗氧化酶活性显著高于E-，丙二醛含量、叶片相对电导率显著低于E-。得出内生真菌可显著改善布顿大麦植株在碱胁迫条件下的光合作用和生理耐受能力，此布顿大麦内生真菌具有开发耐碱新品系的潜在作用。

关键词: 内生真菌, 布顿大麦, 碱胁迫, 生理特性, 光合性能