Dachuan Yin, Jinyu Qi
College of Forestry, Shenyang Agricultural University, ShenYang, People's Republic of China.
PeerJ. 2021 Apr 16;9:e11115. doi: 10.7717/peerj.11115. eCollection 2021.
Ectomycorrhizal fungi (ECMF) can develop the resistance of host plants to heavy metal stress. However, little is known about the response of ECMF to heavy metal exposure. In this study, the growth and physiological indices of under Cd and Cu stress were studied. The growth of on PDA medium under Cd and Cu stress was observed using scanning electron microscopy (SEM). After the addition of Cd and Cu to the medium, the mycelium started twisting, breaking, sticking together, and even dissolving. In the control group, a good and luxuriant mycelium growth of along with the numerous clamp connections was observed. The mycelial biomass decreased with increasing concentrations of heavy metals in a liquid medium. The catalase (CAT), peroxidase (POD), superoxide dismutase (SOD), and ascorbate peroxidase (APX) activities were also investigated, and the results showed that the Cd and Cu treatments caused a significant increase in the antioxidant enzyme activities. The contents of soluble protein, soluble sugar, and free proline in were investigated, and it was found that the contents initially increased and then decreased with the increasing concentrations of Cd and Cu. However, the content of malondialdehyde (MDA) increased with the increasing concentrations of Cd and Cu. In conclusion, the present study provides a theoretical basis for the better utilization of Ectomycorrhizal fungal resources for the remediation of soil contaminated with heavy metal.
外生菌根真菌（ECMF）可以增强宿主植物对重金属胁迫的抗性。然而，关于外生菌根真菌对重金属暴露的反应知之甚少。在本研究中，研究了在镉（Cd）和铜（Cu）胁迫下外生菌根真菌的生长和生理指标。使用扫描电子显微镜（SEM）观察了在Cd和Cu胁迫下外生菌根真菌在马铃薯葡萄糖琼脂（PDA）培养基上的生长情况。向培养基中添加Cd和Cu后，菌丝体开始扭曲、断裂、粘连，甚至溶解。在对照组中，观察到外生菌根真菌的菌丝体生长良好且繁茂，并有大量的锁状联合。在液体培养基中，菌丝体生物量随着重金属浓度的增加而降低。还研究了过氧化氢酶（CAT）、过氧化物酶（POD）、超氧化物歧化酶（SOD）和抗坏血酸过氧化物酶（APX）的活性，结果表明，Cd和Cu处理导致抗氧化酶活性显著增加。对外生菌根真菌中可溶性蛋白、可溶性糖和游离脯氨酸的含量进行了研究，发现其含量随着Cd和Cu浓度的增加先升高后降低。然而，丙二醛（MDA）的含量随着Cd和Cu浓度的增加而增加。总之，本研究为更好地利用外生菌根真菌资源修复重金属污染土壤提供了理论依据。
