Take good care of my fungi - The role of mycetangia in facilitating fungal spore transmission in fungus-farming bark and ambrosia beetles

照顾好我的真菌 - 菌囊在促进真菌种植树皮和豚草甲虫中真菌孢子传播中的作用

• 批准号: 520486374
• 负责人: Dr. Maximilian Lehenberger
• 金额: --
• 依托单位: Abteilung Biochemie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/520486374?language=en
• 关键词: Take; good; care; my; fungi

The origin of a strict obligate mutualism between ambrosia and bark beetles and their species-specific filamentous fungi was one of the milestones in the evolution of these beetles. These two insect groups currently encompass more than 3,500 species worldwide infesting various types of trees and causing major economic damage to forests and plantations around the globe. The mutualistic fungi play multiple essential roles in the lives of ambrosia and bark beetles, for example, as a source of nutrition within an otherwise nutrient-poor environment and as detoxifiers of tree chemical defenses. Therefore, the protection and transport of these fungal symbionts, is of crucial importance for the survival of their beetle hosts, especially during diapause and dispersal flight. All ambrosia beetles and some bark beetles possess mycetangia, specialized structures for the transmission of mutualistic fungi from one nest or gallery to a new one. For decades, mycetangia have been known to harbor only specific mutualist fungi and no other microbes. However, we know little about what is responsible for this selectivity and whether mycetangia also provide nutrition and regulate the growth of their fungal cargo. This project aims to employ chemical, microbiological and ultrastructural methods to try to answer some of the oldest questions in ambrosia and bark beetle mycetangia research. We will examine the impact of mycetangia on the growth of transmitted fungi by providing essential nutrients. Although mycetangia were described to harbor only mutualistic fungi, our preliminary evidence suggests the presence of bacteria that may fix nitrogen. Such bacteria could significantly increase the low nitrogen content of wood and bark substrates, and thus improve beetle fitness. Finally, we will search for antimicrobial compounds that could be responsible for the long-described selectivity of mycetangia allowing the mutualistic fungus to outcompete ubiquitous antagonistic microbes. By establishing new functions for mycetangia, our work will provide fresh insights into the factors driving the success of ambrosia and bark beetles. Such knowledge could eventually be applied to limit the extensive damage caused by these insects to forests and tree plantations throughout the world.

豚草和小蠹与其种特异性丝状真菌之间严格的专性互惠共生关系的起源是这些甲虫进化的里程碑之一。这两类昆虫目前在全世界有3 500多个物种，它们侵扰各种树木，对地球仪各地的森林和种植园造成重大经济损失。互利共生真菌在豚草和小蠹的生活中扮演着多种重要角色，例如，在营养不良的环境中作为营养来源，以及作为树木化学防御的解毒剂。因此，这些真菌共生体的保护和运输，对于甲虫宿主的生存至关重要，特别是在滞育和扩散飞行期间。所有的豚草甲虫和一些树皮甲虫都有菌囊，这是一种专门的结构，用于将互利共生的真菌从一个巢穴或廊道传播到一个新的巢穴或廊道。几十年来，已知菌囊只含有特定的互利真菌，而没有其他微生物。然而，我们对这种选择性的原因以及真菌囊是否也提供营养并调节其真菌货物的生长知之甚少。该项目旨在采用化学，微生物和超微结构的方法，试图回答一些最古老的问题，在豚草和树皮甲虫菌囊的研究。我们将通过提供必需的营养物质来研究菌囊对传播真菌生长的影响。虽然菌囊被描述为只窝藏互利共生的真菌，我们的初步证据表明，可能固定氮的细菌的存在。这种细菌可以显著提高木材和树皮基质的低氮含量，从而提高甲虫适合度。最后，我们将寻找抗菌化合物，可能是负责长期描述的选择性mycetangia允许互惠真菌竞争无处不在的拮抗微生物。通过为菌囊菌建立新的功能，我们的工作将为驱动豚草和树皮甲虫成功的因素提供新的见解。这些知识最终可以应用于限制这些昆虫对世界各地的森林和树木种植园造成的广泛损害。