Osorio J Alexander, De Beer Z Wilhelm, Wingfield Michael J, Roux Jolanda
Department of Microbiology and Plant Pathology, DST/NRF Centre of Excellence in Tree Health Biotechnology (CTHB), Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Private Bag X20, Pretoria, Gauteng, South Africa.
Department of Plant and Soil Sciences, DST/NRF Centre of Excellence in Tree Health Biotechnology (CTHB), Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Private Bag X20, Pretoria, Gauteng, South Africa.
Antonie Van Leeuwenhoek. 2016 Dec;109(12):1555-1571. doi: 10.1007/s10482-016-0757-7. Epub 2016 Aug 25.
Mangrove trees are continuously under stress due to environmental and/or anthropogenic pressures, which expose them to attack by pathogens, compromising their survival. Ophiostomatoid fungi cause sap stain and diseases of a wide spectrum of tree species globally. These fungi infect trees through natural, insect, animal and/or human made wounds. During routine surveys of mangrove trees in South Africa, wounds on branches and stems of Avicennia marina were regularly monitored for the presence of ophiostomatoid fungi at ten study sites in the country. The stems of four mangrove species, A. marina, Bruguiera gymnorrhiza, Rhizophora mucronata and Barringtonia racemosa were also wounded and evaluated for the appearance of these fungi. Ophiostomatoid fungi were obtained from the mangrove associate B. racemosa, but not from any of the true mangroves. Analyses of DNA sequence data for the internal transcribed spacer, β-tubulin, calmodulin and translation elongation factor gene regions revealed that the fungi isolated from the wounds on B. racemosa belong to three species in the Ophiostomataceae, including a new taxon described here as Ophiostoma palustre sp. nov. These results suggest that the mangrove associate B. racemosa is more prone to colonization by ophiostomatoid fungi than the true mangroves.
由于环境和/或人为压力，红树林不断受到胁迫，这使它们容易受到病原体的攻击，从而危及它们的生存。长喙壳类真菌会导致全球范围内多种树木出现流脂病和病害。这些真菌通过自然、昆虫、动物和/或人为造成的伤口感染树木。在南非对红树林进行的常规调查中，在该国的十个研究地点定期监测白骨壤树枝和树干上的伤口，以检查是否存在长喙壳类真菌。还对四种红树植物，即白骨壤、木榄、红海榄和棋盘脚树的树干进行了创伤处理，并评估这些真菌的出现情况。从红树伴生植物棋盘脚树中分离到了长喙壳类真菌，但在任何真正的红树林中都未分离到。对内部转录间隔区、β-微管蛋白、钙调蛋白和翻译延伸因子基因区域的DNA序列数据进行分析后发现，从棋盘脚树伤口分离出的真菌属于长喙壳科的三个物种，包括这里描述的一个新分类群，即沼泽长喙壳菌（Ophiostoma palustre sp. nov.）。这些结果表明，红树伴生植物棋盘脚树比真正的红树林更容易被长喙壳类真菌定殖。
