Fire and Applied Mycology Laboratory, Departments of Agroforestry Sciences and Vegetal Production and Natural Resources, Sustainable Forest Management Research Institute, University of Valladolid (Palencia), Avda. Madrid 44, 34071, Palencia, Spain.
Biodiversity Dynamics Research Group, Naturalis Biodiversity Center, Vondellaan 55, PO Box 9517, 2300 RA, Leiden, The Netherlands.
Microb Biotechnol. 2019 Nov;12(6):1188-1198. doi: 10.1111/1751-7915.13395. Epub 2019 Apr 15.
Cistus ladanifer scrublands, traditionally considered as unproductive, have nonetheless been observed to produce large quantities of king bolete (Boletus edulis) fruitbodies. These pyrophytic scrublands are prone to wildfires, which severely affect fungi, hence the need for fire prevention in producing C. ladanifer scrublands. In addition, B. edulis productions have severely decreased in the last years. A deeper understanding of the B. edulis life cycle and of biotic and abiotic factors influencing sporocarp formation is needed to implement management practices that facilitate B. edulis production. For example, some bacteria likely are involved in sporocarp production, representing a key part in the triple symbiosis (plant-fungus-bacteria). In this study, we used soil DNA metabarcoding in C. ladanifer scrublands to (i) assess the effect of site history and fire prevention treatment on bacterial richness and community composition; (ii) test if there was any correlation between various taxonomic groups of bacteria and mycelial biomass and sporocarp production of B. edulis; and to (iii) identify indicator bacteria associated with the most productive B. edulis sites. Our results show that site history drives bacterial richness and community composition, while fire prevention treatments have a weaker, but still detectable effect, particularly in the senescent plots. Sporocarp production correlated positively with genera in Verrucomicrobia. Several genera, e.g. Azospirillum and Gemmatimonas, were identified as indicators of the most productive sites, suggesting a potential biological role in B. edulis fructification. This study provides a better understanding of the triple symbiosis (plant-fungus-bacteria) involved in C. ladanifer-B. edulis systems.
乳香黄连木灌丛地，传统上被认为是没有生产力的，但人们观察到它们会产生大量的牛肝菌（Boletus edulis）子实体。这些易燃的灌丛地容易发生野火，这对真菌造成了严重的影响，因此需要在生产乳香黄连木灌丛地时进行防火。此外，近年来 B. edulis 的产量严重下降。为了实施有助于 B. edulis 生产的管理实践，需要更深入地了解 B. edulis 的生命周期以及影响子实体形成的生物和非生物因素。例如，一些细菌可能参与了子实体的产生，这是植物-真菌-细菌三重共生的关键部分。在这项研究中，我们使用乳香黄连木灌丛地的土壤 DNA 宏条形码技术来：（i）评估地点历史和防火处理对细菌丰富度和群落组成的影响；（ii）测试各种细菌分类群与牛肝菌菌丝体生物量和子实体产量之间是否存在相关性；（iii）确定与最具生产力的 B. edulis 地点相关的指示细菌。我们的研究结果表明，地点历史驱动了细菌的丰富度和群落组成，而防火处理虽然作用较弱，但仍可检测到，特别是在衰老的样地中。子实体产量与疣微菌门的属呈正相关。一些属，如固氮螺菌属和Gemmatimonas，被鉴定为最具生产力的地点的指示菌，这表明它们在 B. edulis 结实过程中可能具有潜在的生物学作用。这项研究提供了对涉及乳香黄连木-B. edulis 系统的三重共生（植物-真菌-细菌）的更好理解。
