Zhang Bingqian, Li Xiaoguang, Li Guojie, Wang Qi-Ming, Wang Manman
Engineering Laboratory of Microbial Breeding and Preservation of Hebei Province, School of Life Sciences, Institute of Life Sciences and Green Development, Hebei University, Baoding, 071002, Hebei, China.
Science and Technology Division, Hebei University, Baoding, 071002, Hebei, China.
IMA Fungus. 2022 Sep 5;13(1):15. doi: 10.1186/s43008-022-00102-5.
Large numbers of marine glaciers in the Qinghai-Tibet Plateau are especially sensitive to changes of climate and surface conditions. They have suffered fast accumulation and melting and retreated quickly in recent years. In 2017, we surveyed the cold-adapted fungi in these unique habitats and obtained 1208 fungal strains. Based on preliminary analysis of ITS sequences, 41 isolates belonging to the genus Cadophora were detected. As one of the most frequently encountered genera, the Cadophora isolates were studied in detail. Two phylogenetic trees were constructed: one was based on the partial large subunit nrDNA (LSU) to infer taxonomic placement of our isolates and the other was based on multi-locus sequences of LSU, ITS, TUB and TEF-1α to investigate more exact phylogenetic relationships between Cadophora and allied genera. Combined with morphological characteristics, nine Cadophora species were determined, including seven new to science. Among the new species, only C. inflata produces holoblastic conidia and all the others express phialidic conidiogenesis. All isolates have optimum growth temperature at 20 °C or 25 °C. With more species involved, the currently circumscribed genus became obviously paraphyletic. All members are clustered into two main clades: one clade mainly includes most of the Cadophora species which have phialidic conidiogenesis and we refer to as 'Cadophora s. str.'; the remaining Cadophora species have multiform conidiogenesis and are clustered in the second clade, with members of other genera in Ploettnerulaceae interspersed among the subclades. The results show a high diversity of Cadophora from marine glaciers in the Qinghai-Tibet Plateau and most of them are novel species.
青藏高原的大量海洋冰川对气候和地表条件的变化尤为敏感。近年来，它们经历了快速的积累与消融，后退速度很快。2017年，我们对这些独特生境中的嗜冷真菌进行了调查，获得了1208株真菌菌株。基于ITS序列的初步分析，检测到41株属于卡多孢属的分离株。作为最常见的属之一，对卡多孢属分离株进行了详细研究。构建了两棵系统发育树：一棵基于部分大亚基nrDNA（LSU）来推断我们分离株的分类地位，另一棵基于LSU、ITS、TUB和TEF-1α的多位点序列来研究卡多孢属与相关属之间更精确的系统发育关系。结合形态特征，确定了9个卡多孢属物种，其中包括7个新物种。在新物种中，只有膨胀卡多孢产生全壁芽生孢子，其他所有物种均表现为瓶梗式产孢。所有分离株的最适生长温度为20℃或25℃。随着涉及的物种增多，目前界定的该属明显成为并系群。所有成员聚为两个主要分支：一个分支主要包括大多数具有瓶梗式产孢的卡多孢属物种，我们称之为“狭义卡多孢属”；其余的卡多孢属物种具有多种产孢方式，聚集在第二个分支中，普洛特纳菌科其他属的成员散布在亚分支之间。结果表明，青藏高原海洋冰川中的卡多孢属具有高度多样性，且大多数为新物种。
