Brassicaceous roots as an unexpected diversity hot-spot of helotialean endophytes
Brassicaceous roots as an unexpected diversity hot-spot of helotialean endophytes
复制标题
DOI：
10.1186/s43008-020-00036-w
复制
发表时间：
2020-08-11
期刊：
影响因子：
5.4
通讯作者：
Koukol, Ondrej
中科院分区：
文献类型：
--
作者：
Macia-Vicente, Jose G.;Piepenbring, Meike;Koukol, Ondrej
从西欧和南欧收集的芸苔科植物的根中分离出大量的真菌菌株，从而产生了意想不到的丰富的芸苔科植物集合。这些分离株使我们能够对这个helotialean属的根栖成员的生态、形态和系统发育特征提出一个新的和全面的观点。我们基于一个四基因数据集提供了所有分离株的系统发育定位，分析了它们与系统发育关系相关的表型性状，并通过与现有数据库的序列比较推断出物种的潜在分布范围。我们认为7个得到充分支持的系统发育谱系是科学上的新物种。另外6个谱系可能也代表了新物种，但由于缺乏诊断性形态特征而未被描述。我们的研究结果表明，目前所限定的卡多弗拉是一种泛谱系，包含了广泛的形态和生活方式。在新种中，只有两种(C. ferruginea和C.。缢虫属)形成伞柄和分生孢子，典型的cadophora，三种(C. echinata，C.；gamsiiandC。变孢霉)产生肿胀的菌丝片段链，可能具有完整分生孢子的功能，而一个物种（C. fascularis）产生完整的小孢子和分生孢子链。祖先状态重建分析表明，在adophora s.l at.中，从一个被认为是全胚的共同祖先进化出了几次亲性分生现象。尽管具有相对广泛的分布范围，但从序列数据的可用性估计，大多数cadophoralinex是罕见的，而鉴于其有限的分布，五个谱系可能代表地方性关系。我们的数据集，可能是最全面的可用的卡佐多拉，然而，显示了知识的差距，在这个属的系统发育关系，突出需要进一步调查。
A high number of fungal strains were isolated from roots ofBrassicaceaespecies collected across western and southern Europe, resulting in an unexpectedly rich collection ofCadophoraspecies. These isolates enable us to present a new and comprehensive view of the ecological, morphological, and phylogenetic traits of root-inhabiting members of this helotialean genus. We provide phylogenetic placement of all of our isolates based on a four-gene dataset, analyze their phenotypic traits in relation to their phylogenetic relationships, and infer the potential distribution ranges of the species by sequence comparisons with available databases. We consider seven well supported phylogenetic lineages as species new to science. Six further lineages probably also represent new species but remain undescribed due to the lack of diagnostic morphological characters. Our results show thatCadophora, as currently circumscribed, is paraphyletic and encompasses a broad spectrum of morphologies and lifestyles. Among the new species, only two (C. ferrugineaandC. constrictospora) form phialides and conidia typical ofCadophora, three species (C. echinata,C. gamsiiandC. variabilis) produce chains of swollen hyphal segments that may function as holoblastic conidia, and one species (C. fascicularis) produces chains of holoblastic ramoconidia and conidia. Ancestral state reconstruction analysis suggests that phialidic conidiogenesis evolved several times inCadophora s. lat.from a putatively holoblastic common ancestor. MostCadophoralineages are rare as estimated from the availability of sequence data, in spite of having relatively wide distribution ranges, whereas five lineages may represent endemic relationships given their restricted distributions. Our dataset, probably the most comprehensive available forCadophora, nevertheless shows knowledge gaps concerning the phylogenetic relationships within this genus and highlights a need for further investigation.