The James Hutton Institute, Craigiebuckler, Aberdeen AB15 8QH, United Kingdom.
Fungal Biol. 2012 Mar;116(3):354-62. doi: 10.1016/j.funbio.2011.12.002. Epub 2011 Dec 11.
Hypocreopsis rhododendri is a rare fungus that grows on woody stems in hyperoceanic climax scrub on the west coasts of Britain, Ireland, and France. Knowledge of the distribution and abundance of the fungus is based entirely on sporocarp records; it does not account for any occurrence as vegetative mycelia. To address this issue, a H. rhododendri-specific polymerase chain reaction (PCR) was developed and used to assay Corylus avellana (hazel) stems for the presence of H. rhododendri mycelia. The primers ITSHrF and ITSHrR were designed within the internal transcribed spacer 2 region, and their specificity to H. rhododendri was established by their failure to amplify DNA extracted from 14 other Hypocreaceae species. The sensitivity of the assay was demonstrated by amplifying DNA extracted from 4 mg C. avellana wood spiked with 0.0013 % H. rhododendri mycelium. Samples of wood and bark were then taken from around and directly underneath 11 H. rhododendri sporocarps and assayed for the presence of H. rhododendri. PCR products were obtained from a third of the surface bark samples, but only one faint product was obtained from 70 samples taken from beneath the outer bark. The results support the view that H. rhododendri does not form mycelia within stems. We suggest that H. rhododendri is not a saprotrophic fungus, but instead appears to be a parasitic on the wood decay fungus Hymenochaete corrugata, with which it always occurs. Evidence that tissue of H. corrugata is present within the sporocarps of H. rhododendri is discussed.
黄裙竹荪是一种罕见的真菌,生长在英国、爱尔兰和法国西海岸大洋性顶极灌丛的木质茎上。关于该真菌的分布和丰度的知识完全基于子实体的记录;它没有说明任何营养菌丝体的出现。为了解决这个问题,开发了一种黄裙竹荪特异性聚合酶链反应(PCR),并用于检测榛木(榛树)茎中是否存在黄裙竹荪菌丝体。引物 ITSHrF 和 ITSHrR 设计在内转录间隔区 2 区,通过它们不能扩增从 14 种其他拟青霉科物种中提取的 DNA,证明了它们对黄裙竹荪的特异性。该检测方法的灵敏度通过从 4 毫克榛木木材中扩增出 0.0013%黄裙竹荪菌丝体的 DNA 来证明。然后从 11 个黄裙竹荪子实体周围和直接下方采集木材和树皮样本,以检测黄裙竹荪的存在。从三分之一的树皮表面样本中获得了 PCR 产物,但从 70 个取自外树皮下方的样本中仅获得了一个微弱的产物。结果支持黄裙竹荪不在茎内形成营养菌丝体的观点。我们认为黄裙竹荪不是腐生真菌,而是似乎寄生在与其共生的木材腐朽真菌皱木耳上。讨论了皱木耳组织存在于黄裙竹荪子实体中的证据。