Collaborative Research: Seed defense syndromes of tropical forest trees: emergent properties of seed dormancy, defense and microbial interactions

在过去的35年里，一种强有力的植物防御理论已经发展起来，以解释为什么植物物种在其营养组织的毒性和物理韧性方面存在差异。这一理论的应用拓宽了我们对植物-食草动物相互作用的理解，对植物生态学和进化产生了新的见解。这个项目现在将把这个理论扩展到土壤中种子对真菌的防御。种子只有有限的能力来调整资源获取和分配，以跟踪变化的环境或对抗个别威胁。因此，攻击并能杀死种子的真菌应该对一系列特征或种子防御综合征产生强烈的选择。该项目将量化18种树种种子的化学和物理防御，这些树种在巴拿马低地热带森林中表现出广泛的种子特性和发芽行为。实验将确定种子存活的时间过程，扩散到土壤后不同时间的防御效果，以及特定防御与其他防御相关联形成种子防御性状综合征的方式。该研究将为了解种子休眠的生态和进化重要性提供新的视角，并为确定一系列生态重要植物的种子防御综合征迈出了第一步。该项目将为本科生、研究生和博士后提供热带生态学、分子生物学和真菌生物学方面独特的跨学科培训，并将支持来自美国和拉丁美洲的学生进行研究和出版。研究方案和数据集将发布在一个双语的项目网站上，结果将通过亚利桑那大学真菌学植物标本室的公共宣传计划传播。

Over the past 35 years, a robust theory of plant defenses has been developed to explain why plant species vary in the toxicity and physical toughness of their vegetative tissues. Application of this theory has broadened our understanding of plant-herbivore interactions, yielding new insights into plant ecology and evolution. This project will now extend the theory to cover defenses of seeds against fungi in the soil. Seeds have only a limited capacity to adjust resource acquisition and allocation to track a changing environment or to combat individual threats. Fungi that attack and can kill seeds should therefore create strong selection on suites of characteristics, or seed defense syndromes. This project will quantify the chemical and physical defenses of seeds of 18 tree species that exhibit a broad range of seed traits and germination behavior in lowland tropical forest in Panama. Experiments will determine the time course of seed survival, the efficacy of defenses at different times following dispersal onto the soil, and the ways in which particular defenses correlate with others to form syndromes of seed defensive traits. The study will offer a new perspective on the ecological and evolutionary importance of seed dormancy and a first step towards formalizing seed defense syndromes for an array of ecologically important plants. The project will provide unique, cross-disciplinary training in tropical ecology, molecular biology, and fungal biology at the undergraduate, graduate, and post-doctoral levels and will support research and publication by students from the United States and Latin America. Research protocols and data sets will be posted on a bilingual, project website, and results will be disseminated through the public outreach programs of the Mycological Herbarium of the University of Arizona.