Plant Ecology and Nature Conservation Group, Wageningen University, Wageningen, The Netherlands.
PLoS One. 2022 Jul 18;17(7):e0269751. doi: 10.1371/journal.pone.0269751. eCollection 2022.
Ecological intensification has been proposed as an alternative paradigm for intensive agriculture to boost yield sustainably through utilizing ecosystem services. A prerequisite to achieving this is to understand the relations between multiple ecosystem services and production, while taking growth conditions such as nutrient availability into consideration. Here, we conducted a pot-field experiment to study the interactive effects of soil organic matter (SOM) content and arbuscular mycorrhizal fungi (AMF) inoculation on the production of raspberry (Rubus idaeus L.) under four levels of fertilizer application. Raspberry flower number, fruit number and yield only significantly increased with fertilizer inputs but were not impacted by SOM content or AMF inoculation. Fruit set and single berry weight were influenced by both SOM content and AMF inoculation, in complex three-way interactions with fertilizer application. Fruit set of AMF inoculated plants increased with fertilizer inputs in low SOM soils, but decreased with fertilizer inputs under high SOM soils, with the highest fruit set occurring at no fertilizer inputs. In low SOM soils, the relation between single berry weight and fertilizer application was more pronounced in inoculated plants than in non-inoculated plants, while in high SOM soils the relative benefits of AMF inoculation on single berry weight decreased with increasing fertilizer inputs. We attribute the lack of effects of AMF inoculation and SOM content on flower number, fruit number and yield mainly to potential tradeoffs between the experimental variables that all influence resource uptake by plant root systems. Our results suggest that potentially beneficial effects of AMF and SOM can be offset by each other, probably driven by the dynamic relations between AMF and the host plants. The findings reveal fundamental implications for managing AMF inoculation and SOM management simultaneously in real-world agricultural systems.
生态强化被提议作为一种集约化农业的替代范式，通过利用生态系统服务来可持续地提高产量。实现这一目标的前提是要理解多种生态系统服务与生产之间的关系，同时考虑到养分供应等生长条件。在这里，我们进行了一项盆栽-田间实验，研究了土壤有机质（SOM）含量和丛枝菌根真菌（AMF）接种对四种施肥水平下覆盆子（Rubus idaeus L.）生产的互作影响。覆盆子的花数、果数和产量仅随施肥量的增加而显著增加，而不受 SOM 含量或 AMF 接种的影响。结实率和单果重受到 SOM 含量和 AMF 接种的影响，并与施肥之间存在复杂的三向相互作用。在低 SOM 土壤中，接种 AMF 的植物的结实率随施肥量的增加而增加，但在高 SOM 土壤中随施肥量的增加而减少，在不施肥的情况下结实率最高。在低 SOM 土壤中，接种植物的单果重与施肥之间的关系比非接种植物更为显著，而在高 SOM 土壤中，AMF 接种对单果重的相对益处随施肥量的增加而减少。我们认为 AMF 接种和 SOM 含量对花数、果数和产量没有影响，主要是由于实验变量之间存在潜在的权衡，这些变量都会影响植物根系对资源的吸收。我们的研究结果表明，AMF 和 SOM 的潜在有益效应可能相互抵消，这可能是由 AMF 与宿主植物之间的动态关系驱动的。这些发现对同时管理 AMF 接种和 SOM 管理在现实农业系统中具有重要意义。
