\Genetics of differences in host range of a generalist and specialist herbivore

9981671黄金动物物种符合沿着一个连续体，从通才，利用广泛的食物和栖息地，专家，有非常具体的要求。一些以植物为食的昆虫可以成功地食用数百种不同植物物种的叶子，但这些昆虫中的大多数专门针对一种或几种植物物种。相比之下，大多数毁灭性的作物害虫是通才。其中一种是Heliothis virescens，是一种主要的棉花害虫，但也以西红柿，大豆，烟草和其他非农业植物为食。Heliothis subflexa与H. virescens，但是一个极端的专家，只吃一些品种的酸浆（中国灯笼植物）。这两种昆虫可以杂交，后代可以与专家回交。遗传分离的回交后代在特化程度上不同。一种分子基因定位技术，扩增片段长度多态性，将被用来确定哪些基因在这些杂交后代使他们能够消费的通才物种食用植物。从遗传图谱研究中获得的信息将用于研究基因如何相互作用，以确定一个物种的生态位，并可以提供降低害虫遗传潜力的工具。

9981671GouldAnimal species fit along a continuum from generalists, which utilize a broad array of foods and habitats, to specialists, which have very specific requirements. Some plant-feeding insects can successfully consume leaves from hundreds of diverse plant species, but most of these insects specialize on one to a few plant species. In contrast, the majority of devastating crop pests are generalists. One of these, Heliothis virescens, is a major cotton pest but also feeds on tomatoes, soybean, tobacco and other non-agricultural plants. Heliothis subflexa is closely related to H. virescens but is an extreme specialists, only feeding on some species of Physalis (Chinese lantern plant). These two insect species can be hybridized and the offspring backcrossed to the specialist. The genetically segregating backcross offspring vary in degree of specialization. A molecular gene mapping technique, Amplified Fragment Length Polymorphism, will be used to determine which genes in these hybrid offspring enable them to consume the generalist species food plants. Information gained from this genetic mapping research will be used to examine how genes interact in determining the ecological niche of a species, and could provide tools for decreasing the genetic potency of pests.