Vicente Cláudia S L, Soares Miguel, Faria Jorge M S, Espada Margarida, Mota Manuel, Nóbrega Filomena, Ramos Ana P, Inácio Maria L
MED - Mediterranean Institute for Agriculture, Environment and Development & CHANGE - Global Change and Sustainability Institute, Institute for Advanced Studies and Research, Universidade de Évora - Pólo da Mitra, Évora, Portugal.
Instituto Nacional de Investigação Agrária e Veterinária (INIAV, I.P.), Quinta do Marquês, Oeiras, Portugal.
Front Plant Sci. 2022 Jun 14;13:908308. doi: 10.3389/fpls.2022.908308. eCollection 2022.
Considered one of the most devastating plant-parasitic nematodes worldwide, (commonly known as pinewood nematode, PWN) is the causal agent of the pine wilt disease in the Eurasian coniferous forests. This migratory parasitic nematode is carried by an insect vector ( spp.) into the host tree ( species), where it can feed on parenchymal cells and reproduce massively, resulting in the tree wilting. In declining trees, PWN populations are strongly dependent on fungal communities colonizing the host (predominantly ophiostomatoid fungi known to cause sapwood blue-staining, the blue-stain fungi), which not only influence their development and life cycle but also the number of individuals carried by the insect vector into a new host. Our main aim is to understand if PWN-associated mycobiota plays a key role in the development of PWD, in interaction with the PWN and the insect vector, and to what extent it can be targeted to disrupt the disease cycle. For this purpose, we characterized the fungal communities of trees infected and non-infected with PWN in three collection sites in Continental Portugal with different PWD temporal incidences. Our results showed that non-infected mycoflora is more diverse (in terms of abundance and fungal richness) than PWN-infected pine trees in the most recent PWD foci, as opposed to the fungal communities of long-term PWD history sites. Then, due to their ecological importance for PWN survival, representatives of the main ophiostomatoid fungi isolated (, and ) were characterized for their adaptative response to temperature, competition in-between taxa, and as food source for PWN. Under the conditions studied, isolates showed promising results for PWN control. They could outcompete the other species, especially , and significantly reduce the development of PWN populations when compared to (routinely used for PWN lab culturing), suggesting this to be a natural antagonist not only for the other blue-stain species but also for the PWN.
（通常被称为松材线虫，PWN）被认为是全球最具毁灭性的植物寄生线虫之一，是欧亚针叶林松材线虫病的病原体。这种迁移性寄生线虫由昆虫媒介（ 属物种）携带进入寄主树（ 属物种），在那里它可以取食薄壁细胞并大量繁殖，导致树木枯萎。在衰退的树木中，松材线虫种群强烈依赖定殖在寄主上的真菌群落（主要是已知会导致边材蓝变的长喙壳类真菌，即蓝变真菌），这些真菌不仅影响它们的发育和生命周期，还影响昆虫媒介携带到新寄主中的个体数量。我们的主要目标是了解与松材线虫相关的真菌群落是否在松材线虫病的发展中与松材线虫和昆虫媒介相互作用时发挥关键作用，以及在多大程度上可以针对它来破坏疾病循环。为此，我们对葡萄牙大陆三个具有不同松材线虫病发病时间的采集地点中感染和未感染松材线虫的树木的真菌群落进行了表征。我们的结果表明，在最新的松材线虫病疫点，未感染松材线虫的树木的真菌区系（在丰度和真菌丰富度方面）比感染松材线虫的松树更为多样，这与长期存在松材线虫病历史的地点的真菌群落情况相反。然后，由于它们对松材线虫生存具有生态重要性，对分离出的主要长喙壳类真菌（ 、 和 ）的代表菌株进行了温度适应性反应、类群间竞争以及作为松材线虫食物来源的特性研究。在所研究的条件下， 菌株在控制松材线虫方面显示出有前景的结果。它们能够胜过其他物种，尤其是 ，并且与 （通常用于松材线虫实验室培养）相比，能显著减少松材线虫种群的发展，这表明它不仅是其他蓝变物种的天然拮抗剂，也是松材线虫的天然拮抗剂。
