Phylogeny of Triticeae

谷物族是一群草，包括三个最重要的农作物属：小麦（Triticum）、大麦（Hordeum）和黑麦（Secale）。这些属中的每一个都被广泛研究过。该部落还包括34个其他属，其中一些属是主要的牧草，其中许多属具有可以引入谷类牧草的遗传特征（例如耐盐、耐旱）。这些非作物属不太为人所知。通过植物育种进行的基因转移在涉及近亲植物时最为成功。因此，对小麦、大麦和黑麦在系统发育上如何相互关联以及与部落其他成员之间的关系建立严格的模型将是有用的。关于谷类部落的花和叶结构有大量可用的数据集，但这些数据在系统发育上是模糊的，并且没有足够的特征来可靠地测量相关性。这项研究将超越花和叶的数据，探索这些植物的DNA变异。初步数据表明，叶绿体DNA序列或这些序列的样本可以比较部落成员，并将提供一个物种与主要作物最密切相关的估计。此外，由于DNA甚至可以从非常年轻的植物中提取，它将提供一种早期的方法来识别只有在开花时才能识别的植物。亲缘关系的估计和DNA标记将为植物育种提供重要的工具。一个额外的好处将是了解植物DNA的一般结构以及它在不同植物群体中如何变化。

The cereal tribe is a group of grasses that includes three of the most important genera of crop plants: Triticum (wheat), Hordeum (barley), and Secale (rye). Each of these genera has been extensively studied. The tribe also includes 34 other genera, some of which are major forage grasses and many of which have genetic characteristics that would be desirable to introduce into the cereal grasses (e.g. salt tolerance, drought tolerance). These non-crop genera are much less well-known. The transfer of genes through plant breeding is most successful when it involves closely related plants. Therefore, it would be useful to have rigorous models of how wheat, barley, and rye are phylogenetically related to each other and to other members of the tribe. There is a substantial data set available on floral and leaf structure for the cereal tribe, but these data are phylogenetically ambiguous, and there are insufficient characteristics to measure relatedness with confidence. This study will go beyond the floral and leaf data to explore variation with the DNA of these plants. Preliminary data suggest that the chloroplast DNA sequences, or samples of those sequences, can be compared for the members of the tribe and will provide an estimate of which species are most closely related to the major crops. Also, because DNA can be extracted from even very young plants, it will provide an early way to identify plants that could only otherwise be identified at flowering. Both the estimates of relatedness and the DNA markers will provide important tools for plant breeders. An added benefit will be information on the structure of plant DNA in general and how it varies in different plant groups.