Marasmius palmivorus is a marasmioid fungal species that exhibits parasitic behaviour, although most marasmioids are rarely parasitic. The fungus has been reported to cause fruit bunch rot disease of oil palm and coconut, but only a few studies on its pathogenic behaviour are available, particularly on oil palm. Hence, there is a need to assess the ability of the fungus to act as a pathogen and to study its molecular evolution and taxonomy. Nine isolates of M. palmivorus were successfully isolated from basidiocarps and diseased fruitlets of oil palm collected from oil palm plantations and were morphologically characterized on potato dextrose agar (PDA) followed by molecular identification based on nucleotide sequence alignments of internal transcribed spacer (ITS) regions of ribosomal RNA (rRNA) gene clusters with sequences from GenBank. Koch's Postulates confirmed that M. palmivorus could infect oil palm fruitlets with symptoms similar to those observed for bunch rot disease. Molecular phylogenetic studies using nucleotide sequences of ITS and the nuclear ribosomal large subunit (nLSU) showed that isolates sharing the same phenotypic characteristics of Marasmius palmivorus and Marasmiellus palmivorus are monophyletic and share a common ancestor. The fungus has also been shown to be more closely related to the genus Marasmius than Marasmiellus; therefore, we support retention of the taxon name of the pathogen causing bunch rot disease of oil palm as Marasmius palmivorus.

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导致油棕果串腐烂的Marasmioid真菌Marasmius palmivorus的系统发生和致病性评估

棕榈果马拉松（Marasmius palmivorus）是一种具有寄生特性的Marsmioid真菌，尽管大多数Marasmioids很少寄生。据报道，这种真菌会引起油棕和椰子的果实腐烂病，但有关其致病性的研究很少，特别是在油棕上。因此，需要评估真菌作为病原体的能力并研究其分子进化和分类学。九株分离的掌纹支原体成功地从油棕种植园的油棕果基和患病小果中分离得到，并在马铃薯葡萄糖琼脂（PDA）上进行形态学表征，然后基于核糖体RNA（rRNA）内部转录间隔区（ITS）区域的核苷酸序列比对进行分子鉴定基因与GenBank的序列聚在一起。Koch的假设证实，棕榈食分枝杆菌可感染油棕果，其症状与束腐病相似。使用ITS核苷酸序列和核糖体大亚基（nLSU）进行的分子系统发育研究表明，分离株具有相同的表型特征，如Marasmius palmivorus和Marasmiellus palmivorus。是单系的，有着共同的祖先。这种真菌也被证明是更密切相关的属皮比Marasmiellus ; 因此，我们支持保留引起油棕束腐烂病的病原体的分类名称为Marasmius palmivorus。