Key Laboratory of Basic Pharmacology and Joint International Research Laboratory of Ethnomedicine of Ministry of Education, Zunyi Medical University, Zunyi 563003, China.
Bioresource Institute for Healthy Utilization, Zunyi Medical University, Zunyi, 563003, China.
Int J Mol Sci. 2020 Jan 2;21(1):316. doi: 10.3390/ijms21010316.
are tropical orchid plants that host diverse endophytic fungi. The role of these fungi is not currently well understood in plants. We morphologically and molecularly identified these fungal endophytes, and created an efficient system for evaluating the pathogenicity and symptoms of endophytic fungi on and though in vitro co-culturing. ReThe colony morphological traits of myco-endophytes (DMEs) were recorded for their identification. Molecular identification revealed the presence of Colletotrichum tropicicola, Fusarium keratoplasticum, Fusarium oxysporum, Fusarium solani, and Trichoderma longibrachiatum. The pathogenicity results revealed that T. longibrachiatum produced the least pathogenic effects against D. nobile protocorms. In seedlings, T. longibrachiatum showed the least pathogenic effects against D. officinale seedlings after seven days. C. tropicicola produced highly pathogenic effects against both Dendrobium seedlings. The results of histological examination of infected tissues revealed that F. keratoplasticum and T. longibrachiatum fulfill Koch's postulates for the existence of endophytes inside the living tissues. The DMEs are cross-transmitted inside the host plant cells, playing an important role in plant host development, resistance, and alkaloids stimulation.
这些热带兰花植物是多种内生真菌的宿主。目前，这些真菌在植物中的作用还不是很清楚。我们通过形态学和分子学鉴定了这些真菌内生菌，并通过体外共培养建立了一个评估内生真菌对铁皮石斛和金钗石斛致病性和症状的有效系统。我们记录了内生真菌（DME）的菌落形态特征，进行鉴定。分子鉴定表明存在炭疽菌、拟茎点霉、尖孢镰刀菌、腐皮镰刀菌和长枝木霉。致病性结果表明，长枝木霉对铁皮石斛原球茎的致病作用最小。在幼苗中，长枝木霉对金钗石斛幼苗的致病作用在七天后最小。炭疽菌对两种石斛幼苗都产生了高度的致病性作用。感染组织的组织学检查结果表明，拟茎点霉和长枝木霉满足内生菌在活组织内存在的科赫假设。内生真菌在宿主植物细胞内交叉传播，在植物宿主发育、抗性和生物碱刺激方面发挥着重要作用。
