CAREER: Nectar chemistry and ecological and evolutionary tradeoffs in plant adaptation to microbes and pollinators

植物与各种生物体相互作用。花朵和蜜源植物产生的花蜜适合吸引蜜蜂或蜂鸟等有益生物。然而，细菌和真菌等微生物也栖息在花朵中，并会减少植物的繁殖。植物特性可以减少花蜜中的微生物生长，但这也可能减少传粉者的访问。该项目将调查由不同生物授粉的植物（例如鸟类与蜜蜂与苍蝇）是否在减少微生物生长的能力方面存在差异，以及花蜜化学是否与微生物生长有关。该项目将研究花蜜特性是否可以用来培育植物，使其对有害微生物更具抵抗力，而不会减少对传粉者的吸引力。对微生物的抗性在农业环境中是有益的，其中花卉病原体可以限制粮食生产，但作物仍然依赖于授粉。这项研究将把植物表型的变化与微生物丰度和物种组成以及微生物对植物-动物相互作用的影响联系起来。该项目将使用一个易于处理的系统：在花蜜中生长的微生物，它可以影响花卉游客和植物繁殖。测试的基本假设是，促进或减少微生物生长的植物性状，以及群落环境（例如，传粉者的存在）影响生态和进化结果。研究活动将使用1）共花植物物种群落和2）柳叶菜内的基因型进行。实验将描述微生物生长、花蜜化学的变化、微生物对植物繁殖和访花者行为的影响以及这些因素的相互作用。实验和分析将揭示花蜜化学的变化如何与花蜜中的微生物生长和物种组成相关，以及随后对植物-传粉者相互作用（包括植物繁殖）的影响。在柳叶菜基因型的实验将阐明微生物如何影响微进化的花性状在社区的背景下。这个项目将吸引来自一个大的本科班的学生参加以教师为动机的研究项目。学生们还将参加推广到当地社区的授粉友好种植园艺和景观。该项目将支持来自不同背景和代表性不足的学生参加与项目目标相关的独立项目。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

Plants interact with a variety of organisms. The flowers and the nectar plants produce are adapted to attract beneficial organisms like bees or hummingbirds. However, microbes like bacteria and fungi also inhabit flowers and can reduce plant reproduction. Plant traits can reduce microbial growth in nectar, but this may also reduce pollinator visitation. This project will investigate if plants that are pollinated by different organisms (e.g. birds vs bees vs flies) differ in their ability to reduce microbial growth and if nectar chemistry is associated with microbial growth. This project will examine if nectar traits can be used to breed plants to be more resistant to harmful microbes without reducing attraction to pollinators. Resistance to microbes is beneficial in agricultural contexts where floral pathogens can limit food production but crops still rely on pollination. This research will link variation in plant phenotype to microbial abundance and species composition, and microbial effects on plant-animal interactions. This project will use a tractable system: the microorganisms growing in floral nectar, which can influence floral visitors and plant reproduction. The underlying hypothesis tested is that plant traits that facilitate or reduce microbial growth, and the community context (e.g., presence of pollinators) influence ecological and evolutionary outcomes. The research activities will be performed using 1) a community of co-flowering plant species and 2) genotypes within Epilobium canum. Experiments will characterize variation in microbial growth, nectar chemistry, and microbial effects on plant reproduction and floral visitor behavior and the interactions of these factors. Experiments and analysis will reveal how variation in nectar chemistry is associated with microbial growth and species composition in nectar, and subsequent effects on plant-pollinator interactions including plant reproduction. Experiments across Epilobium genotypes will elucidate how microbes affect microevolution of floral traits in a community context. This project will engage students from a large undergraduate class to participate in practitioner-motivated research projects. Students will also participate in outreach to local communities on pollinator-friendly plantings for horticultural and landscaping. The project will support students recruited from diverse and underrepresented backgrounds to participate in independent projects related to project objectives.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.