Expoloring the Intensity and Consequences ofPhenological Assortative Mating in Plant Populations.

长期以来，人们一直认为，开花时间的变化会诱导植物进行分类交配：早开花的植物主要与其他早熟的植物交配，而晚开花的植物往往与其他晚开花的植物交配。理论预测，与随机交配相比，当“喜欢与喜欢”交配时，后代包含更多具有极端基因组合的个体。这可以促进植物对组合性状的选择反应。但分类也可能增加分类性状和其他性状之间的遗传协方差。如果是这样，对组合性状的选择可以加速或减速，这取决于对相关性状的选择方向。这将是对分类交配及其对植物遗传变异的影响的第一次全面研究。田间和温室实验将提供关于交配模式如何调节对选择的反应的强化信息。拟议的工作将加强植物改良的标准育种方法。它在转基因作物的生物安全分析中也有应用。了解开花时间对作物-杂草杂交率的影响是确定特定作物品种在转基因可能从种植中逃脱并进入杂草物种的地区是否不安全的关键因素。

It has been long supposed that variation in flowering time induces assortative mating in plants: Early bloomers mate predominantly with other early plants, while late bloomers tend to mate with other late plants. Theory predicts that when 'like mates with like,' the offspring generation contains more individuals with extreme gene combinations, compared to random mating. This can facilitate plant response to selection on the assorting trait. But assortment may also increase the genetic covariance between the assorting trait and other traits. If so, selection on the assorting trait can be either accelerated or decelerated, depending on the direction of selection on the correlated trait. This will be the first comprehensive study of assortative mating and its impacts on plant genetic variation. Field and greenhouse experiments will provide reinforcing information on the ways that mating patterns can modulate the response to selection.The proposed work will enhance standard breeding methods for plant improvement. It also has applications in bio-safety analysis for genetically engineered crops. Understanding the contribution of flowering time to crop-weed hybridization rates is a key factor in determining whether particular crop varieties will be unsafe in areas where the modified gene can potentially 'escape' from cultivation and into weed species.