Yokoya Kazutomo, Jacob Alison S, Zettler Lawrence W, Kendon Jonathan P, Menon Manoj, Bell Jake, Rajaovelona Landy, Sarasan Viswambharan
Royal Botanic Gardens Kew, Richmond, Surrey TW9 3DS, UK.
Department of Biology, Illinois College, Jacksonville, IL 62650-2299, USA.
Microorganisms. 2021 Apr 10;9(4):792. doi: 10.3390/microorganisms9040792.
About 90% of species are endemic to the biodiversity hotspot of Madagascar. This terrestrial habitat-specific genus received little study for fungal diversity to support conservation. We evaluated the diversity of culturable fungi of 11 species and soil characteristics from six sites spanning a >40 km radius in and along the region's inselbergs. Peloton-forming fungi were grown in vitro from root/protocorm slices and positively identified using DNA sequencing. The fungal diversity was then correlated with soil pH, NON, P, and K. All species harbored either putative mycorrhizal associates in the complex or Hypocreales fungi. Operational Taxonomic Units (OTUs) were most prevalent in all soil types while OTUs were found in species inhabiting granite/rock outcrops in moist soil (seepage areas). Most species were present in soil with low NON and P levels with diversity of mycorrhizal fungi inversely correlated to NON levels. Of the different orchid life stages sampled, only one species () yielded putative mycorrhizal fungi from juvenile stages. As diversity of mycorrhizal fungi of spp. was negatively correlated with NON, and majority of the studied taxa were found in soils with low NON and P contents, reintroduction studies must include analysis of N and P in detail. For the first time, we showed that the assemblage of culturable fungi in the roots of habitat-specific species of (Orchidaceae) are intimately tied to specific soil characteristics.
约90%的物种是马达加斯加生物多样性热点地区的特有物种。这个特定于陆地栖息地的属在真菌多样性方面几乎没有得到研究以支持保护工作。我们评估了该地区inselbergs及其周边半径超过40公里的六个地点的11个物种的可培养真菌多样性和土壤特征。从根/原球茎切片中在体外培养形成菌丝球的真菌，并使用DNA测序进行阳性鉴定。然后将真菌多样性与土壤pH值、氮、磷和钾进行关联。所有物种在其根系复合体中都含有假定的菌根共生体或肉座菌目真菌。操作分类单元（OTUs）在所有土壤类型中最为普遍，而在潮湿土壤（渗流区）中栖息于花岗岩/岩石露头的物种中也发现了OTUs。大多数物种存在于低氮和低磷水平的土壤中，菌根真菌的多样性与氮水平呈负相关。在所采样的不同兰花生命阶段中，只有一个物种（）在幼年阶段产生了假定的菌根真菌。由于石豆兰属物种的菌根真菌多样性与氮呈负相关，并且在所研究的分类群中大多数发现于低氮和低磷含量的土壤中，重新引入研究必须详细分析氮和磷。我们首次表明，石豆兰属（兰科）特定栖息地物种根系中可培养真菌的组合与特定土壤特征密切相关。
