The Genetic Basis of Morphological Differences Between Two Species of Setaria (Poaceae)

小米是亚洲一些地区人们消费的一种小谷物，因此对第三世界的农业具有潜在的价值。这个项目研究了谷子的基因组，以确定它与其近缘玉米的相似性，并确定它与野草的相似性。通过研究谷子与其野生祖先绿谷子杂交的后代，将绘制出基因组图谱。英国诺里奇约翰·英尼斯中心(JIC)的科学家已经完成了一个这样的杂交；他们使用小米和大米的基因来确定小米基因组的结构。利用他们的植物材料，确定了谷子基因组的几个区域，这些区域控制着种头的大小和形状，这影响着谷粒的产量。本项目的具体目标是：1.在JIC的植株中定位来自玉米的基因。这将允许根据图谱位置确定哪些玉米基因也在谷子中发挥功能。2.将发育重要基因放在JIC图谱上，以确定它们是否定位到任何已知影响种子头结构的区域。如果他们映射到同一地区，这并不能证明他们控制着种头发育，但如果他们映射到其他地方，那么他们可以被排除在候选之外。3.在这两种谷子之间进行另一个杂交，以创造第二个更大的植物集合，以重复实验。4.开始从我们的植物和JIC植物中培育近等基因系，以验证作图研究的结果。区别绿谷子和小米的特征对于草本植物来说并不罕见。它们主要是近缘部分的大小和数量的数量变化，这种变化区分了大多数草种。因此，这项研究将有助于了解谷子中的基因，也将提供一瞥植物多样性的遗传基础。

Foxtail millet is a minor grain consumed by people in some parts of Asia, and is thus of potential value to Third-World agriculture. This project studies the genome of foxtail millet to determine how similar it is to its relative corn, and also to determine similarities to wild grasses. A genome map will be developed by studying the offspring of crosses between foxtail millet and its wild ancestor, green millet. One such cross hasalready been done by scientists at the John Innes Centre (JIC) in Norwich, England; they have used genes from millet and from rice to determine the structure of the millet genome. Using their plant material, several regions of the millet genome were identified that control the size and shape of the seed head, which influences the amount of grain produced. The specific goals in this project are to: 1. Locate genes from corn in the plants from the JIC. This will allow determination of which corn genes also function in millet, based on map position. 2. Place developmentally important genes on the JIC map to determine if they map to any of the regions known to affect the structure of the seed head. If they map to the same region, it will not prove that they control seed head development, but if they map elsewhere, then they can be excluded as candidates. 3. Make another cross between the two millet species to create a second, larger set of plants, to replicate the experiment. 4. Begin development of near-isogenic lines from our plants and the JIC plants, to verify the results of the mapping studies. The characterstics that distinguish green millet and foxtail millet are not unusual for grass species. They are mostly quantitative changes in the relatives sizes and numbers of parts, the sorts of changes that distinguish most species of grasses. This study will thus help understand the genes in foxtail millet, but will also provide a glimpse of the genetic basis of plant diversity.