Moreira Xoaquín, Abdala-Roberts Luis, Zas Rafael, Sampedro Luis
Misión Biológica de Galicia (MBG-CSIC), Apdo. 28, 36080, Pontevedra, Galicia, Spain.
Departamento de Ecología Tropical, Campus de Ciencias Biológicas y Agropecuarias, Universidad Autónoma de Yucatán, Apartado Postal 4-116, Itzimná, 97000, Mérida, Yucatán, México.
Planta. 2025 Aug 28;262(4):91. doi: 10.1007/s00425-025-04813-y.
Nutrient availability, namely soil phosphorus, modulates trade-offs between constitutive and induced defences in maritime pine, with high phosphorus weakening these trade-offs and shaping plant allocation to different defensive strategies. Abiotic factors modulate trade-offs between plant functions, but their influence on trade-offs between constitutive and induced defences remains poorly understood. We tested for such trade-offs in maritime pine (Pinus pinaster) and examined whether soil phosphorus availability affected these defensive correlations. We conducted a greenhouse experiment with six-month-old pine seedlings from 33 half-sib families, exposing half of the plants from each family to either low or high soil phosphorus availability, one of the main limiting factors for pine development in the study region. Within each fertilization group, we applied jasmonic acid to induce defences in half of the plants per family. Defensive traits measured included resin production and phenolic compound levels. As predicted, we found significant negative correlations between constitutive and induced defences for both defensive traits under low phosphorus availability. However, these correlations were absent under high phosphorus conditions, indicating that overabundance of this nutrient weakened defensive allocation constraints. These findings highlight the role of nutrient availability in shaping plant defence allocation constraints, potentially shaping the correlated evolution of plant defensive strategies.
养分有效性，即土壤磷含量，调节着海岸松组成型防御和诱导型防御之间的权衡，高磷会削弱这些权衡，并影响植物对不同防御策略的分配。非生物因素调节着植物功能之间的权衡，但其对组成型防御和诱导型防御之间权衡的影响仍知之甚少。我们在海岸松（Pinus pinaster）中测试了这种权衡，并研究了土壤磷有效性是否会影响这些防御相关性。我们用来自33个半同胞家系的六个月大的松树幼苗进行了一项温室实验，将每个家系的一半植株暴露于低或高土壤磷有效性环境中，磷是研究区域松树生长的主要限制因素之一。在每个施肥组中，我们对每个家系的一半植株施用茉莉酸以诱导防御。所测量的防御性状包括树脂产量和酚类化合物水平。正如预期的那样，我们发现在低磷有效性条件下，两种防御性状的组成型防御和诱导型防御之间存在显著的负相关。然而，在高磷条件下这些相关性不存在了，这表明这种养分的过量会削弱防御分配限制。这些发现突出了养分有效性在塑造植物防御分配限制方面的作用，可能会影响植物防御策略的协同进化。
