REU: Genetic Variability in Bryophyte Populations

REU：苔藓植物种群的遗传变异

• 批准号: 8909200
• 负责人: Robin Kimmerer
• 金额: $ 1.6万
• 依托单位: Centre College of Kentucky
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-08-01 至 1990-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8909200&HistoricalAwards=false
• 关键词: REU; Genetic; Variability; Bryophyte; Populations

The evolutionary significance of sex is a central problem in evolutionary ecology. There has been a proliferation of models which predict the relative benefits of sexual vs. asexual reproduction but few empirical tests exist. The goal of this research is to provide just such a test, using the forest bryophyte, Tetraphis pellucida. Bryophytes are ideal systems in which to test hypotheses concerning the effectiveness of sexual or asexual reproduction in different environments since they exhibit a high degree of habitat specificity and wide array of reproductive modes. It has been demonstrated that levels of genetic variability in some asexual species are equivalent to those of sexual species. Asexual reproduction does not necessarily yield reduced genetic variability, especially in those organisms in which the germ line is not isolated from somatic mutation. The traditional view that sex enhances fitness through the creation of genetic diversity may be inappropriate in bryophytes. The long-term goal of this research is to examine the possibility that somatic non-germ cell mutation, as a source of genetic variability, may equal or exceed that of sexual recombination in mosses. Certain background information is required prior to such an investigation. This Research Planning Grant would permit Dr. Kimmerer to complete preliminary studies and to develop methods which would support the long-term goal. The activities proposed here constitute essential preparation for a major research effort.

性别的进化意义是进化生态学中的核心问题。 模型已经扩散，可以预测性与无性繁殖的相对益处，但很少存在经验检验。 这项研究的目的是使用森林苔藓植物Tetraphis pellucida仅提供这样的测试。 苔藓植物是在不同环境中对性或无性繁殖有效性进行测试的理想系统，因为它们表现出高度的栖息地特异性和广泛的生殖模式。 已经证明，某些无性物种的遗传变异水平等于性物种。 无性繁殖不一定会降低遗传变异性，尤其是在那些未从体细胞突变中分离出生殖系的生物。 传统的观点是，通过创造遗传多样性来增强健身性可能是不合适的苔藓植物。 这项研究的长期目标是检查体细胞非脂肪细胞突变作为遗传变异性的来源，可能等于或超过苔藓中性重组的可能性。 在进行此类调查之前，需要某些背景信息。 这项研究计划赠款将允许Kimmerer博士完成初步研究并开发支持长期目标的方法。 这里提出的活动构成了重大研究工作的基本准备。