Abstract：
Evolutionary relationships between the morphological and ecological traits of fungi are poorly understood. The appendages of chasmothecia, which are sexual reproductive organs of Erysiphaceae, are considered to play a crucial role in the overwintering strategies of these fungi on host plants. Previous studies suggested that both the host type and appendage morphology evolved at the same nodes and transitioned from complex appendages on deciduous hosts to simple appendages on herb/evergreen hosts. However, the evolutionary dependence between host type and appendage morphology remains unproven owing to the limited species data used in analyses. To elucidate the evolutionary relationship between host type and appendage morphology, we used phylogenetic comparative methods (PCMs) to investigate the state transition, ancestral state, evolutionary dependence, and contingent evolution within Erysipheae, the largest and most diverse tribe in Erysiphaceae. Our PCMs, based on a comprehensive data set of Erysipheae, revealed that the most ancestral states were deciduous host types and complex appendages. From these ancestral states, convergent evolution toward the herb/evergreen host types and simple appendages occurred multiple times at the same nodes. For the first time in Erysiphaceae, we detected an evolutionary dependence between host type and appendage morphology. This is one of the few examples in which evolutionary dependence between host phenology and morphological traits in plant-parasitic fungi was demonstrated using PCMs. Appendage simplification on herb/evergreen hosts and complications on deciduous hosts can be reasonably explained by the functional advantages of each appendage type in different overwintering strategies. These expected appendage functions can explain approximately 90% of host type and appendage morphology combinations observed in the analyzed taxa. However, our results also highlighted the occurrence of evolutionary shifts that deviate from the expected advantages of each appendage morphology. These seemingly irrational shifts might be interpretable from the flexibility of overwintering strategies and quantification of appendage functions.
摘要：
真菌的形态和生态特征之间的进化关系知之甚少。chasmothecia的附属物，它们是赤子科的性生殖器官，被认为在这些真菌对寄主植物的越冬策略中起着至关重要的作用。先前的研究表明，寄主类型和附属物形态都在相同的节点上进化，并从落叶寄主上的复杂附属物过渡到草本/常绿寄主上的简单附属物。然而,由于分析中使用的物种数据有限，宿主类型和附属物形态之间的进化依赖性仍未得到证实。为了阐明宿主类型和附肢形态之间的进化关系，我们使用系统发育比较方法(PCM)来研究状态转变，祖先国,进化依赖，和赤耳内部的偶然进化，木耳科中最大和最多样化的部落。我们的PCM,基于一组完整的Erysipheae数据，发现最祖先的状态是落叶寄主类型和复杂的附属物。从这些祖先国家，在同一节点多次向草药/常绿寄主类型和简单附属物的融合进化。第一次在Erysiphaceae，我们检测到宿主类型和附肢形态之间的进化依赖性。这是使用PCMs证明植物寄生真菌中寄主物候和形态性状之间进化依赖性的少数例子之一。草本/常绿寄主的附属物简化和落叶寄主的并发症可以通过不同越冬策略中每种附属物类型的功能优势来合理解释。这些预期的附肢功能可以解释在分析的分类单元中观察到的大约90％的宿主类型和附肢形态组合。然而,我们的结果还强调了进化变化的发生,这些变化偏离了每个附肢形态的预期优势.从越冬策略的灵活性和附属物功能的量化可以解释这些看似不合理的变化。
