DOES MYCORRHIZAL SPECIFICITY AFFECT ORCHID DECLINE AND RARITY?
DOES MYCORRHIZAL SPECIFICITY AFFECT ORCHID DECLINE AND RARITY?
复制标题
DOI：
10.3732/ajb.1200117
复制
发表时间：
2012-10-01
影响因子：
3
通讯作者：
Jacquemyn, Hans
中科院分区：
文献类型：
--
作者：
Bailarote, Bruno Cachapa;Lievens, Bart;Jacquemyn, Hans
本研究的目的：兰花依赖于菌根真菌种子萌发，许多物种在其生命周期的后期阶段保持联系。由于兰花对真菌的严重依赖，有人认为菌根特异性的程度可能与兰花物种的稀有性和长期生存有关，特别是在高度退化或破碎的景观中。为了验证这一假设，我们比较了两个物种，在比利时和欧洲其他地区的下降显着不同的菌根群落。方法：菌根协会进行了调查，在5个人口的Anacamptis morio和Dactylorhiza fuchsii在比利时。ITS为基础的DNA阵列用于同时检测和鉴定的广泛的担子菌菌根真菌。菌根特异性，测量系统发育多样性，每个人口进行了评估，比较species.Key results：对于这两个物种，菌根的合作伙伴的系统发育相关的程度是低的，这两个物种都与大量的真菌谱系Tulasnellaceae家族的分支。与预期相反，明显具有抗衰退能力的物种与比衰退物种更少的真菌操作分类单位相关，并且种群间菌根群落的系统发育相关性在稳定的兰花中高于衰退的兰花。虽然我们的研究结果并没有对兰花持久性的原因提出详细的见解，他们确实表明兰花的稀有性和持久性与真菌多样性不一定相关，其他因素在决定兰花持久性方面可能更重要。
Premise of the study: Orchids rely on mycorrhizal fungi for seed germination, and many species maintain associations during later stages in their life cycle. Because of the critical dependence of orchids on fungi it has been suggested that the degree of mycorrhizal specificity may be associated with rarity and long-term survival of orchid species, especially in highly degraded or fragmented landscapes. To test this hypothesis, we compared mycorrhizal communities in two species that differed significantly in decline in Belgium and other parts of Europe.Methods: Mycorrhizal associations were investigated in five populations of Anacamptis morio and Dactylorhiza fuchsii in Belgium. ITS-based DNA arrays were used for simultaneous detection and identification of a wide range of basidiomycetous mycorrhizal fungi. Mycorrhizal specificity, measured as phylogenetic diversity, was assessed for each population and compared between species.Key results: For both species, the degree of phylogenetic relatedness of the mycorrhizal partners was low, and both species were associated with a large number of fungal lineages related to clades of the Tulasnellaceae family. Contrary to expectations, the species that was apparently resilient to decline was associated with fewer fungal operational taxonomical units than the declining species was, and the phylogenetic relatedness of mycorrhizal communities among populations was higher in the stable than in the declining orchid.Conclusions: Although our results do not present detailed insights into the causes of orchid persistence, they do suggest that orchid rarity and persistence are not necessarily related to fungal diversity and that other factors may be more important in determining orchid persistence.