Allevato Daniella M, Kiyota Eduardo, Mazzafera Paulo, Nixon Kevin C
Section of Plant Biology, School of Integrative Plant Science, Cornell University, Ithaca, NY, United States.
Departamento de Biologia Vegetal, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, Brazil.
Front Plant Sci. 2019 Mar 6;10:258. doi: 10.3389/fpls.2019.00258. eCollection 2019.
Studies examining the diversity of plant specialized metabolites suggest that biotic and abiotic pressures greatly influence the qualitative and quantitative diversity found in a species. Large geographic distributions expose a species to a great variety of environmental pressures, thus providing an enormous opportunity for expression of environmental plasticity. , a neotropical genus of Rutaceae, is rich in alkaloids, terpenoids, and coumarins, and is the only commercial source of the alkaloid pilocarpine for the treatment of glaucoma. Overharvesting of species in this genus for pilocarpine, has threatened natural populations of the species. The aim of this research was to understand how adaptation to environmental variation shapes the metabolome in multiple populations of the widespread species . LCMS data from alkaloid and phenolic extracts of leaf tissue were analyzed with environmental predictors using unimodal unconstrained and constrained ordination methods for an untargeted metabolomics analysis. PLS-DA was used to further confirm the chemoecotypes of each site. The most important variables contributing to the alkaloid variation between the sites: mean temperature of wettest quarter, as well as the soil content of phosphorus, magnesium, and base saturation (V%). The most important contributing to the phenolic variation between the sites: mean temperature of the wettest quarter, temperature seasonality, calcium and soil electrical conductivity. This research will have broad implications in a variety of areas including biocontrol for pests, environmental and ecological plant physiology, and strategies for species conservation maximizing phytochemical diversity.
对植物特殊代谢产物多样性的研究表明，生物和非生物压力对一个物种中发现的定性和定量多样性有很大影响。广阔的地理分布使一个物种面临各种各样的环境压力，从而为环境可塑性的表达提供了巨大机会。毛果芸香属是芸香科的一个新热带属，富含生物碱、萜类化合物和香豆素，是用于治疗青光眼的生物碱毛果芸香碱的唯一商业来源。该属物种因毛果芸香碱而被过度采收，已威胁到该物种的自然种群。本研究的目的是了解对环境变化的适应如何塑造广泛分布物种多个种群的代谢组。使用单峰无约束和约束排序方法，将来自叶片组织生物碱和酚类提取物的液相色谱-质谱数据与环境预测因子进行分析，以进行非靶向代谢组学分析。偏最小二乘判别分析（PLS-DA）用于进一步确认每个地点的化学生态型。导致各地点生物碱差异的最重要变量：最湿润季度的平均温度，以及土壤中的磷、镁含量和碱基饱和度（V%）。导致各地点酚类差异的最重要因素：最湿润季度的平均温度、温度季节性、钙和土壤电导率。这项研究将在包括害虫生物防治、环境和生态植物生理学以及最大化植物化学多样性的物种保护策略等多个领域产生广泛影响。
