Phylogeny and Dispersal in the Grass-Feeding Delphacid Planthoppers (Insecta: Hemiptera: Delphacidae)

飞虱科（Delphacidae），通常称为稻飞虱，是一种相对较大且分布广泛的植物饲养昆虫。 稻飞虱的经济重要性是有据可查的。 该科包括至少55种以经济植物为食的物种，包括世界十大主要粮食作物中的五种的主要害虫，如水稻，甘蔗，玉米，芋头和谷物。 稻飞虱作为害虫的重要性，特别是在水稻上，推动了对其控制的研究。 植物损害是由各种植物疾病的直接喂养和传播引起的，这些疾病每年能够给全世界的农业产业造成数百万美元的损失。 一些稻飞虱群体往往是专门的食草动物（包括谷类作物草），而其他群体则以莎草，灯心草和双子叶植物为食。 根据环境的线索，食草稻飞虱物种的幼虫发育成短翅或长翅的形式。 短翅型在有利的条件下产生更多的后代，而长翅型在条件不利时能够分散到新的环境中。 尽管稻飞虱在科学和经济上的重要性已经得到了很好的证实，但稻飞虱种群之间的进化关系基本上是未知的，这实际上限制了对这些昆虫的生物学研究。 本研究的目的是重建，使用解剖比较和DNA分析相结合的证据，在飞虱家庭Delphacidae基于这些昆虫的全球样本的进化关系。 通过在地理分布和宿主植物关联的背景下确定和解释稻飞虱的进化历史，研究人员将检验他们的假设，即宿主植物向草的转移是进化成功的原因（即，通过该研究产生的对稻飞虱进化的理解对于控制已知的稻飞虱作物害虫以及对于控制新的稻飞虱害虫的未来爆发将是特别重要的。 这项工作还将提供一个框架，用于整合对单个稻飞虱物种进行的大量科学研究。 研究人员还将开发互联网可访问的密钥，以帮助识别稻飞虱物种;这些密钥对研究这些昆虫的科学家以及受这些昆虫影响的农业环境中的工人都具有相当大的价值。 此外，通过这项研究进行的尖端进化分析将作为对其他植物和动物群体进行类似研究的模型。

The insect family Delphacidae, commonly called planthoppers, is a relatively large and widely distributed group of plant-feeding insects. The economic importance of planthoppers is well documented. The family includes at least 55 species that feed on economic plants and includes major pests of five of the top ten major world food crops, such as rice, sugarcane, maize, taro, and cereals. The importance of planthoppers as pests, particularly on rice, has driven research on their control. Plant damage results both from direct feeding and transmission of various plant diseases capable of causing millions of dollars of damage annually to the worldwide agricultural industry. Some planthopper groups tend to be specialist grass feeders (including cereal crop grasses), whereas other groups feed on sedges, rushes, and dicots. Based on environmental cues, nymphs of grass-feeding planthopper species develop into either short-winged or long-winged forms. Short-winged forms produce more offspring under favorable conditions, while long-winged forms are able to disperse into new environments when conditions are unfavorable. Despite the well-established scientific and economic importance of planthoppers, evolutionary relationships among planthopper groups are essentially unknown, effectively limiting biological studies on these insects. The purpose of this research is to reconstruct, using a combination of evidence taken from anatomical comparison and DNA analysis, the evolutionary relationships within the planthopper family Delphacidae based on a worldwide sample of these insects. By determining and interpreting planthopper evolutionary history in the contexts of geographic distribution and host plant association, the researchers will test their hypothesis that host plant shifts to grasses are responsible for the evolutionary success (i.e., greater diversity and range) of advanced planthoppers.The understanding of planthopper evolution generated by this research will be of particular importance to the control of known planthopper crop pests, as well as for the control of future outbreaks of novel planthopper pests. This work will also provide a framework for integrating the considerable number of scientific studies that have been conducted on individual planthopper species. The researchers will also develop Internet accessible keys to aid in the identification of planthopper species; these keys will be of considerable value to both scientists studying these insects, as well as workers in agriculture environments affected by these insects. Additionally, the cutting-edge evolutionary analyses carried out through this research will serve as a model for similar studies on other plant and animal groups.