接种DSE下黄芪光合特征对高温胁迫的响应及因素分析  

Response of photosynthetic characteristics of Astragalus to high temperature stress and influencing factor analysis under DSE inoculation

作　　者：毕银丽 冯馨月[1] 柯增鸣 BI Yinli;FENG Xinyue;KE Zengming(Institute of Ecological Environment Restoration in Mine Areas of West China,Xi’an University of Science and Technology,Xi’an 710054,Shaanxi,China;State Key Laboratory of Coal Resources and Safe Mining,China University of Mining and Technology(Beijing),Beijing 100083,China)

机构地区：[1]西安科技大学西部矿山生态环境修复研究院,陕西西安710054 [2]中国矿业大学(北京)煤炭资源与安全开采国家重点实验室,北京100083

出　　处：《菌物学报》2023年第11期2294-2308,共15页Mycosystema

基　　金：国家重点研发计划(2022YFF1303303);国家自然科学基金面上项目(51974326)。

摘　　要：深色有隔内生真菌(dark septate endophyte,DSE)作为一类植物内生真菌,接菌后如何提高植物应对逆境的生长能力一直是研究热点。为探究接种DSE下黄芪光合特征对高温胁迫的响应及其影响因素,本试验设置接菌区(接种DSE)和对照区,以黄芪为供试对象,分别进行高温胁迫处理,胁迫温度为42℃,胁迫时间设置1、3、7和11d共4个梯度,每个梯度3个重复,测定土壤化学性质、根系指标、叶片形态及光合特征。结果表明:随着高温胁迫时间增加,接菌区与对照区黄芪叶片的面积、气孔张开密度、叶绿素含量与根尖数均呈下降趋势,降低范围分别为55.5%–66.3%、69.6%–81.0%、68.2%–81.2%和56.7%–59.8%。然而,接种DSE提高了黄芪叶片周长、面积、气孔张开密度、叶绿素含量、蒸腾速率及净光合速率(P<0.05),表明接种DSE显著降低了高温对黄芪光合特征指标的影响,提高了黄芪抗高温胁迫的能力。进一步采用主成分与结构方程模型分析发现,土壤速效磷、速效钾、根长、叶绿素a、气孔张开密度与净光合速率为显著的正向关系(P<0.05),说明接种DSE可以通过调节黄芪根系、叶片光合色素、气孔等指标来提高黄芪的光合速率。本研究重点探讨高温胁迫下接种DSE对黄芪光合特征的影响,在利用DSE促进植物生长、提高植物耐高温性及光合效率方面具有一定的创新性。研究结果可为DSE在高温逆境下资源利用提供科学依据。Dark septate endophyte(DSE)improving the growth ability of plants to cope with adversity has always been a research hotspot.In this study the response of photosynthetic characteristics of Astragalus to high temperature stress and its influencing factors under DSE inoculation(Alternaria sp.)were observed.Astragalus membranaceus was used as the test object and 42°C high temperature stress treatment was carried out.The stress duration of 1,3,7 and 11 days,and 3 replicates for each treatment were set up.The soil chemical properties,root indexes,leaf morphology and photosynthetic characteristics were determined.The results showed that with the increase of high temperature stress time,the leaf area,stomatal opening density,chlorophyll content and root tip number of inoculated and uninoculated Astragalus plants reduced by 55.5%–66.3%,69.6%–81.0%,68.2%–81.2%and 56.7%–59.8%,respectively.However,inoculation with DSE Alternaria sp.increased leaf circumference and area,stomatal opening density,chlorophyll content,transpiration rate and net photosynthetic rate(P<0.05)of the plants,indicating that inoculation with DSE significantly reduced the influence of high temperature on the photosynthetic characteristics of Astragalus membranaceus,and improved the ability of the Astragalus plants to resist high temperature stress.Further analysis of principal component and structural equation models showed that soil available phosphorus,available potassium,root length,chlorophyll a,stomatal opening density and net photosynthetic rate were significantly positive(P<0.05),indicating that inoculation with DSE could improve the photosynthetic rate of Astragalus by adjusting the root system,leaf photosynthetic pigment,stomata and other indicators.The research results provide a scientific basis for the resource utilization of DSE under high temperature adversity.

关 键 词：链格孢属 深色有隔内生真菌 高温胁迫 光合特征 黄芪 

分 类 号：S567.239[农业科学—中草药栽培]