Collaborative Research: DNA "Fingerprinting" to Estimate Male and Female Fitness in Heliopsis helianthoides (Asteraceae)

大多数开花植物通过产生花粉或种子，既有雄花又有雌花。理论表明，雌性生殖的成功通常受到可用于种子生产的资源的限制。植物的雄性功能受到植物散布花粉的能力的限制。这导致了一种预测，即花对传粉者的吸引力对种子生产的影响相对有限，但对花粉的传播有很大影响，因此植物是否适合作为雄性植物。尽管预测了雄性适合度对花卉吸引进化的重要性，但父系繁殖成功在自然种群中的分布一直非常难以衡量。DNA“指纹”可以用来在植物种群中明确地确定父子关系，因此可以用来估计父系繁殖成功。将开发一种方法来测量草原植物向日葵的父系和母系适合度，这项合作研究包括密集的现场和实验室部分。这三个目标是：1)记录高变位基因座在向日葵中的变异；2)确定这些座位的遗传方式；3)使用已知百分比的苗木来确定这些高变位基因座是否可以用来在向日葵野生种群中分配父权。这项工作将提供必要的基本数据，以应用DNA“指纹”技术来评估目前关于花结构进化的假说。

Most flowering plants function as both male and females, through the production of either pollen or seeds. Theory suggests that female reproductive success is usually limited by resources available for seed production. The male function in plants is limited by the ability of the plant to disperse pollen. This leads to the prediction that the attractiveness of flowers to pollinators has relatively limited effect on the production of seed, but a large effect on the dispersal of pollen, and hence the fitness of the plant as a male. Despite this predicted importance of male fitness to the evolution of floral attraction, the distribution of paternal reproductive success in natural populations has been exceedingly difficult to measure. DNA "fingerprinting" can be used to determine paternity unambiguously in plant populations, and therefore to estimate paternal reproductive success. Methods will be developed to measure paternal and maternal fitness in the prairie plant Heliopsis helianthoides in a collaborative study that has both intensive field and laboratory components. The three objectives are: 1) to document variation among H. helianthoides for hypervariable loci; 2) to determine the mode of inheritance for these loci; 3) to use seedlings of known percentage to determine if the hypervariable loci can be used to assign paternity in a wild population of H. helianthoides. This work will contribute the basic data necessary to apply the technique of DNA "fingerprinting" to the evaluation of current hypotheses on the evolution of floral structures.