Lin Lei-Chen, Ye Yu-Sin, Lin Wan-Rou
Department of Forestry and Natural Resources, National Chiayi University, Chiayi, 60004, Taiwan.
Bioresource Collection and Research Center (BCRC), Food Industry Research and Development Institute (FIRDI), No. 331, Shih-Pin Road, Hsinchu, 30062, Taiwan.
Braz J Microbiol. 2019 Jan;50(1):185-193. doi: 10.1007/s42770-018-0011-8. Epub 2018 Dec 3.
Ericoid mycorrhiza can improve the competitiveness of their host plants at the ecosystem level. The ability of ericoid mycorrhizal fungi to thrive under harsh environmental conditions suggests that they are capable of decomposing plant organic matter. This study aims to characterize 2 strains of root-cultivable endophytic fungi, RooDK1 and RooDK6, from Rhododendron ovatum Planch using colony and hyphal morphology, molecular analysis, observations of mycorrhiza, and investigations of adaptation to different sources of organic matter. Nitrogen utilization was also investigated by assessing protease production and growth on different nitrogen sources. Morphological studies indicated that both species are ericoid mycorrhizal fungi; our molecular studies confirmed RooDK1 as Oidiodendron maius and classified RooDK6 as Pezicula ericae. We observed that only RooDK1 can assist in host plant survival by degrading organic matter. This species also secretes protease and has the highest nitrate reductase activity of these 2 endophytes. Thus, RooDK1 has a greater ability to help the host plants thrive in a harsh habitat.
石楠状菌根可在生态系统层面提高其寄主植物的竞争力。石楠状菌根真菌在恶劣环境条件下茁壮生长的能力表明它们能够分解植物有机质。本研究旨在利用菌落和菌丝形态、分子分析、菌根观察以及对不同有机质来源适应性的研究，对来自卵叶杜鹃的2株可在根部培养的内生真菌RooDK1和RooDK6进行特性描述。还通过评估蛋白酶产生情况以及在不同氮源上的生长来研究氮利用情况。形态学研究表明这两个物种均为石楠状菌根真菌；我们的分子研究证实RooDK1为大孢奥氏霉，并将RooDK6归类为石楠盘菌。我们观察到只有RooDK1能够通过降解有机质来协助寄主植物存活。该物种还分泌蛋白酶，并且在这2种内生真菌中具有最高的硝酸还原酶活性。因此，RooDK1在帮助寄主植物在恶劣生境中茁壮成长方面具有更强的能力。
