Collaborative Research: The Evolution of Heterostylous Breeding Systems in Populations of Oxalis Alpina in the Sky Islands of the United States and Mexico

合作研究：美国和墨西哥天空群岛高山酢浆草种群异柱育种系统的进化

• 批准号: 0614208
• 负责人: Travis Glenn
• 金额: --
• 依托单位: University of Georgia Research Foundation Inc
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-10-01 至 2011-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0614208&HistoricalAwards=false
• 关键词: Collaborative; Research; Evolution; Heterostylous; Breeding

Breeding systems determine how individuals get together to reproduce, and influence the amount of genetic diversity in populations and the potential for speciation. Plants provide model systems for understanding factors promoting changes in breeding systems because of their variability in reproductive systems. In heterostyly, distinctive floral forms are associated with chemical incompatibilities that usually prevent mating between similar forms and promote crossing between forms (outcrossing). Oxalis alpina appears to be evolving a new breeding system, with loss of one floral morph in some populations. To test previous models indicating that changes in self-incompatibility are responsible for breeding system evolution, crosses will be carried out to determine whether changes in incompatibility are more common in populations where heterostyly is more highly modified. Outcrossing rates will be measured because greater self-compatibility could retard loss of morphs. The relative fitness of offspring from crosses within and between different morphs will be measured to understand the importance of inbreeding depression in this breeding system change. Research will focus on populations of Oxalis alpina occurring in mountain ranges extending through Mexico, Arizona, and New Mexico.This research provides insights into evolutionary factors that underlie modifications of plant breeding systems, and reproductive systems in general. The research fosters an international collaboration, with participation of faculty, graduate students, and undergraduates from U.S. and Mexican institutions. This project is being supported by the Office of International Science and Engineering.

繁殖系统决定个体如何聚集在一起繁殖，并影响种群中遗传多样性的数量和物种形成的潜力。植物由于其生殖系统的可变性，为理解促进育种系统变化的因素提供了模型系统。在异种花柱中，不同的花形式与化学不相容有关，这通常会阻止相似形式之间的交配，并促进形式之间的杂交（异交）。高山草似乎正在进化出一种新的繁殖系统，在一些种群中失去了一种花的形态。为了验证先前的模型，即自交不亲和性的变化是繁殖系统进化的原因，将进行杂交，以确定不亲和性的变化是否在异种异种修饰程度较高的种群中更常见。将测量异交率，因为更大的自相容性可以延缓形态的丧失。将测量不同变种内部和不同变种之间杂交后代的相对适合度，以了解近交抑制在这种育种系统变化中的重要性。研究将集中在发生在墨西哥、亚利桑那州和新墨西哥州的山脉上的高山草种群。这项研究提供了对植物育种系统和生殖系统修改背后的进化因素的见解。这项研究促进了国际合作，来自美国和墨西哥机构的教师、研究生和本科生都参与其中。该项目得到国际科学与工程办公室的支持。