【作者】 王朵； 贺超； 孙翔； 左易灵； 张亚娟； 贺学礼；

【Author】 Duo Wang;Chao He;Xiang Sun;Yiling Zuo;Yajuan Zhang;Xueli He;School of Life Sciences,Hebei University;Institute of Medicinal Plant Development,Chinese Academy of Medical Sciences & Peking Union Medical College;

【机构】 河北大学生命科学学院； 中国医学科学院北京协和医学院药用植物研究所；

【摘要】 干旱和镉(Cd)污染是影响植物生长和产量的主要非生物胁迫因子,而通过接种有益内生真菌能够促进药用植物生长。为了评估暗色有隔内生真菌(dark septate endophytes,DSE)对各种非生物胁迫的耐受性,本研究通过固体平板培养和液体摇床培养探究了不同浓度PEG(0、9、18和27%)和Cd浓度(0、2、50和100 mg/L)下10种DSE[Microsphaeropsis cytisi(Mc)、Alternaria alstroemeriae(Aa)、Stagonosporopsis lini(Sl)、Neocamarosporium phragmitis(Np)、Paraphoma chlamydocopiosa(Pc)、Macrophina phaseolina(Mp’)、Papulaspora equi(Pe)、Alternaria tellustris(At)、Macrophomina pseudopholina(Mp)和Paraphoma radicina(Pr)]的生长性能。此外,研究了不同田间持水量(70%和40%)和Cd浓度(0、5、10和15 mg Cd/kg)下DSE(Np和At)对黄芪Astragalus membranaceus var.mongholicus生长的影响。结果表明,在PEG浓度为18%时,Aa、Np、Pc、Mp’和Mp菌落生长率有最大值,Aa、Np和At在100 mg Cd/L时仍保持生长活性。干旱与Cd胁迫固体培养结果表明,Np生长率明显优于其他菌株。液体培养时Np和Aa生物量最高,在18%与25 mg Cd/L浓度下,生物量最高为1.39g和1.23g,而At在18%与50 mg Cd/L浓度下,生物量最高为1.71g。Np菌株CAT和POD活性在27%与50 mg Cd/L和27%与25 mg Cd/L浓度下分别达到峰值。与对照组相比,分别增加了416.97%和573.12%。不同干旱和镉复合胁迫下,Aa、Np和At对SOD活性有积极影响,而这些菌株的谷胱甘肽(GSH)含量增加。结构方程模型分析表明,Aa对生物量有积极影响,对Cd含量有负面影响,而Np和At对Cd含量有积极。在40%田间持水量和40%田间持水量与5 mg Cd/kg土壤复合胁迫下,接种Np和At显著提高了黄芪根系生物量。这些数据为筛选优良抗旱耐镉DSE菌种和绿色药用植物栽培和生产提供科学支持。更多还原

【Abstract】 Drought and cadmium（Cd） pollution are the main abiotic stress factors affecting the growth and yield of plants, and the inoculation of beneficial endogenous fungi can promote the growth of medicinal plants. To evaluate the tolerance of dark septate endophytes（DSE） to various abiotic stresses, this study investigated the growth performance of 10 DSEs [Microsphaeropsis cytisi（Mc）, Alternaria alstroemeriae（Aa）, Stagonosporopsis lini（Sl）, Neocamarosporium phragmitis（Np）, Paraphoma chlamydocopiosa（Pc）, Macroph phaseolina（Mp’）, Papulaspora equi（Pe）, Alternaria tellustris（At）, Macrophomina pseudopholina（Mp）, and Paraphoma radicina（Pr）] at different concentrations of PEG（0, 9, 18, and 27%） and Cd（0, 2, 50, and 100 mg/L） via solid plate culture and liquid shaking culture. Additionally, the effect of DSE（Np and At） on the growth of Astragalus membranaceus var. mongholicus at different field water capacities（70% and 40%） and at different CdCl₂ concentrations（0, 5, 10, and 15 mg Cd/kg） in soil was investigated.The results demonstrated that the colony growth rates of Aa, Np, Pc, Mp’, and Mp were the first to reach the maximum diameter at a PEG concentration of 18%. Aa, Np, and At remained growthactive at 100 mg Cd/L. The results of the drought-combined-with-Cd-stress solid culture indicated that the growth rate of Np was significantly superior to that of the other strains. In the liquid culture condition, the biomasses of Np and Aa were the highest, with biomasses of 1.39 g and 1.23 g under the concentration of 18% + 25 mg Cd/L, and At had the highest biomass of 1.71 g at 18% + 50 mg Cd/L concentration, respectively. The CAT and POD activities of Np reached their peak levels at concentrations of 27% + 50 mg Cd/L and 27% + 25 mg Cd/L, respectively. Compared to the control,these levels indicated increases of 416.97% and 573.12%, respectively. Aa, Np, and At positively influenced SOD activity, and the glutathione（GSH） contents of these strains were increased under different combined stressors of drought and Cd. The structural-equation-modeling（SEM）analysis revealed that Aa positively influenced biomass and negatively affected Cd content, while Np and At positively influenced Cd content. Under the stress of 40% field-water capacity and the synergistic stress of 40% field-water capacity and 5 mg Cd/kg soil, Np and At significantly increased root weight of A. membranaceus var. mongholicus. These data provide scientific support for the screening of excellent drought-resistant and cadmium-tolerant DSE strains and the cultivation and production of green medicinal plants.更多还原