Evolutionary History of Defense Genes in the Genus Zea and Family Poaceae: Insight from DNA Sequence Data

植物保护自己免受食草动物和病原体侵害的机制已经在当代种群中得到了广泛的研究。相比之下，人们对植物防御的长期进化动力学知之甚少。这项研究将利用DNA序列中包含的信息来调查这些长期动态。包括驯化玉米在内的3种玉米防御基因的DNA序列多样性。并对不同属禾本科植物的防御基因差异进行分析。这些分析将为植物防御基因的进化史和当今多样性提供一个前所未有的图景。除了促进我们对植物进化的理解外，这项研究的结果可能对农业非常有价值。例如，对防御等位基因进行广泛取样可以确定对发展可持续虫害防治手段有用的遗传资源。这项研究可能会确定进化稳定的植物防御，从而可能提供对寄生虫的持久抗性。对种群间和种群内多样性的分析将为制定有效的遗传资源收集策略提供必要的数据，以便进行保护和作物改良。研究生和本科生将参与拟议的研究，并将有机会学习分子技术和分子进化分析。

The mechanisms by which plants defend themselves against herbivores and pathogens have been subject to extensive investigation in contemporary populations. In comparison, relatively little is known about the long-term evolutionary dynamics of plant defenses. This research will use the information contained in DNA sequences to investigate these long-term dynamics. DNA sequence diversity of defense genes in three Zea species, including the domesticate Z. mays ssp. mays (corn), and divergence of defense genes among different genera of grasses will be analyzed. These analyses will provide an unprecedented picture of the evolutionary history and present day diversity of plant defense genes.In addition to advancing our understanding of plant evolution, the results from this research may be very valuable to agriculture. For example, the extensive sampling of defense alleles may identify genetic resources useful for developing sustainable means of pest control. This research may identify plant defenses that are evolutionarily stable and, thus, may provide durable resistance against parasites. Analysis of inter- and intra-population diversity will provide data necessary for developing efficient strategies for collecting genetic resources for conservation and crop improvement. Graduate and undergraduate students will participate in the proposed research and will have opportunities to learn molecular techniques and molecular-evolutionary analyses.