A pipeline of resistance genes to Phytophthora infestans from wild Solanum species and their accelerated isolation using Illumina sequencing methods

马铃薯晚疫病是由马铃薯晚疫病菌（Phytophthora infestans，Pi）引起的世界性重要病害之一。英国农民每年喷洒10-15次来控制枯萎病，在发展中国家，晚疫病也会大大降低马铃薯产量。在2007年潮湿的夏天，欧洲的枯萎病压力如此严重，以至于对枯萎病控制化学品的需求超过了供应。马铃薯育种极其缓慢且效率低下-最受欢迎的英国品种（Maris Piper）已经超过30年-因此控制马铃薯枯萎病的最佳方法是从野生马铃薯亲戚中分离出多种抗P. infestans（Rpi）基因，并将这些Rpi基因引入受欢迎的品种。目前尚不清楚最持久的策略是否包括在同一品种中堆叠多个Rpi基因，或种植具有不同Rpi基因的同一品种的混合物，或每年使用不同的Rpi基因。任一策略都需要分离多个Rpi基因。Rpi基因的分离涉及在枯萎病抗性和枯萎病敏感植物之间进行杂交，并对下一代中抗性和敏感性的分离进行评分。使用新的测序方法，我们将能够通过与已知抗性基因的序列相似性来鉴定总是与抗性相关的候选抗性基因。将这些候选基因转化（使用农杆菌）到枯萎病敏感马铃薯品种Desiree中，并测试转化植物的枯萎病抗性。我们在欧盟和BBSRC的前期工作中分离到了两个Rpi基因Rpi-mcq 1和Rpi-oka 1.1。为了充分探索这种方法，我们将分离多个额外的Rpi基因。我们正在绘制更多来自其他茄属物种的Rpi基因，为未来的Rpi基因分离和部署创造一个管道，目标是为马铃薯作物提供持久的枯萎病抗性。我们的工作将揭示Rpi基因是如何进化的，也使我们能够识别这些Rpi基因识别并赋予反应性的病原体分子。我们计划在此项目期间进行抗枯萎病转基因马铃薯的小规模田间试验。

Late blight of potato caused by Phytophthora infestans (Pi) is one of the world's most important crop diseases. UK farmers spray 10-15 times per year for blight control, and in developing countries, late blight also dramatically reduces potato yields. In the wet summer of 2007, blight pressure in Europe was so severe that demand for blight control chemicals exceeded supply. Potato breeding is extremely slow and inefficient- the most popular UK variety (Maris Piper) is over 30 years old- so the best way to control potato blight is to isolate multiple Resistance to P. infestans (Rpi) genes from wild potato relatives and introduce these Rpi genes into popular varieties. It is not clear if the most durable strategy will involve stacking multiple Rpi genes in the same variety, or planting mixtures of the same variety with different Rpi genes, or using different Rpi genes each year. Either strategy requires the isolation of multiple Rpi genes. Isolation of Rpi genes involves making crosses between blight resistant and blight sensitive plants, and scoring the segregation of resistance and sensitivity in the next generation. Using new sequencing methods, we will be able to identify candidate resistance genes that are always associated with resistance by their sequence similarity to known resistance genes. These candidate genes will be transformed (using Agrobacterium) into blight sensitive potato variety Desiree, and transformed plants tested for blight resistance. We have isolated two Rpi genes, Rpi-mcq1 and Rpi-oka1.1 in previous work funded by EU and by BBSRC. To fully explore this approach, we will isolate multiple additional Rpi genes. We are mapping more Rpi genes from additional Solanum species, creating a pipeline for future Rpi gene isolation and deployment, with the goal of providing durable blight resistance to the potato crop. Our work will shed light on how Rpi genes evolve, and also enable us to identify the pathogen molecules that these Rpi genes recognize and confer responsiveness to. We plan to carry out small scale field trials of GM blight resistant potatoes during the course of this project.