SBIR Phase I: Control of Lesion Nematodes by Transgenic RNA Interference

这项小企业创新研究(SBIR)第一阶段的研究将产生对植物寄生线虫具有抗性的转基因作物，重点是病损线虫(Pratylichus)。植物寄生线虫在美国每年造成80亿美元的损失，是最难控制的植物病原体之一。转基因作物有很大的机会通过提高产量和降低投入成本为种植者提供经济利益，并取代有毒的杀线虫杀虫剂。该项目将使用RNA干扰(RNAi)通过沉默线虫基因来控制病损线虫。我们将测试特定双链RNA(DsRNAs)抑制基本寄生虫基因的有效性。DISTISTION建立了高效的植物毛状根转基因植物表达系统来筛选候选dsRNAs。防治其他植物寄生线虫取得了良好的效果，该系统也可用于病斑线虫的防治。目的I将包括从斯氏原虫中选择、克隆和测序可能在所有病损线虫中必不可少的基因靶标。在目标II中，将在毛状根系统中检测目标基因的RNAi效力。在第一阶段的结束时，预计将有几个显示病损线虫繁殖减少的目标基因被选择用于第二阶段的全植物转化。玉米可能是第一个引入转基因病损线虫抗性的作物，玉米是美国最大的种植面积和最有价值的作物之一。该项目的更广泛影响将是减少美国农业中广泛使用杀虫剂的需求，并对抗影响玉米生产的侵略性寄生虫。

This Small Business Innovation Reserach (SBIR) Phase I research will generate transgenic crops with resistance to plant parasitic nematodes with a focus on the lesion nematode (Pratylenchus). Plant parasitic nematodes annually cause damage of $8 billion in the U.S. and are among the most difficult plant pathogens to control. Transgenic crops have a significant opportunity to provide economic benefit to growers through improved yields and decreased input costs and to replace toxic nematicidal pesticides. This project will use RNA interference (RNAi) to control the lesion nematode by silencing nematode genes. We will test the efficacy of specific double-stranded RNAs (dsRNAs) to inhibit essential parasite genes. Divergence has established an efficient transgenic hairy root in planta expression system to screen candidate dsRNAs. Promising results controlling other plant parasitic nematodes have been achieved and the same system can be utilized for lesion nematode. Objective I will include the selection, cloning, and sequencing of gene targets from Pratylenchus scribneri that are likely to be essential in all lesion nematodes. In objective II, the RNAi potency of target genes will be assayed in the hairy root system. At the conclusion of Phase I, it is anticipated that several target genes demonstrating reduction in lesion nematode reproduction will be selected for Phase II whole plant transformation. A likely crop for the first introduction of transgenic lesion nematode resistance is corn, one of the largest acreage and most valuable crops in the U.S.The broader impact of this project will be to reduce the need for extensive use of pesticides in US agriculture and to counter an aggressive parasite that affects the production of corn.