褐飞虱新型短翅群体对田间群体的替换能力及机理研究

Most pest control measures are based on population suppression strategy. As a recently proposed pest control strategy, population replacement strategy owns broad application prospect, however, it has only been reported in a few insect species such as fruit flies and mosquitoes. This application team has good research basis on the brown planthopper (BPH) Nilaparvata lugens, one of the major insect pests of rice, RNAi and CRISPR/Cas9 techniques, and has also obtained a batch of genes that may be involved in the wing differentiation of N. lugens. In this proposal, we will get 2-3 BPH target genes that are suitable for the gene-drive system, by using RNAi and CRISPR/Cas9 techniques; then obtain new-type short-winged BPH populations with a CRISPR/Cas9 gene drive system. Using the new-type short-winged populations as materials, their ecological fitness and mating competition with natural BPH populations from rice fields will be assessed. The population replacement ability of the new-type short-winged populations in cages with natural BPH populations will be studied, and its mechanism will be also analyzed. The aim of this proposal is trying to achieve population replacement of natural BPH populations by the new-type short-winged populations, thus laying the foundation of new pest control measures for BPH. This proposal pioneers population replacement study induced by a gene-drive system in agricultural insect pests. It is meaningful for development of new pest control measures and reduced loss caused by the pests.

大部分害虫防治方法基于种群抑制策略。而种群替换策略作为一种最近提出的策略，应用前景广阔，但仅在果蝇、蚊子等少数几种昆虫中有报道。本申请团队在水稻重要害虫褐飞虱、RNAi技术和CRISPR/Cas9技术等方面均有较好基础，且已获得一批可能调控褐飞虱翅型分化的候选基因。本项目拟在此基础上，利用RNAi和CRISPR/Cas9技术筛选获得适用于基因驱动系统的褐飞虱靶标基因2-3个，然后构建获得含CRISPR/Cas9基因驱动系统的褐飞虱新型短翅群体并评估其生态适应性，研究新型短翅群体与褐飞虱田间群体的交配竞争能力以及对田间群体的替换能力，并揭示其机理；期望利用这些新型短翅群体替换褐飞虱田间群体，从而阻断其迁飞，为褐飞虱防控新方法的研发奠定基础。本项目的创新点在于：率先在农业害虫中建立基因驱动系统来诱发害虫的群体替换。对研发害虫防控新方法，减轻害虫危害具有重要意义。

褐飞虱Nilaparvata lugens是水稻重要害虫，具有典型的翅二型现象（长翅型、短翅型）。种群替换策略作为一种最近提出的策略，重点是改变害虫的性状或能力，应用前景比较广阔，但仅在果蝇、蚊子等少数几种昆虫中有报道。本项目明确了褐飞虱的胚胎发育过程，通过转录组数据分析、RNAi和CRISPR/Cas9实验，发现了3个可用于褐飞虱新型短翅群体构建的靶基因：胰岛素受体基因1（NlInR1）、5-羟色胺受体基因5HT1A、鸟氨酸脱羧酶基因等。优化了褐飞虱的基因编辑系统，包括启动子vasa、U6a和β2-tubulin、可视化标记基因（半胱氨酸亚磺酸脱羧酶基因CSAD）、以及sgRNA的结构。基于分裂式驱动方法分别构建Cas9品系与gRNA品系，构建了靶向NlInR1的褐飞虱新型短翅群体，并评价新型短翅群体对褐飞虱田间种群的替换能力。以本项目为第一标注在PLoS Biology、Insect Biochemistry and Molecular Biology、Insect Science、International Journal of Biological Macromolecules、Journal of Integrative Agriculture等刊物上发表SCI论文9篇；以第二标注在Insect Science、Pest Management Science等刊物上发表SCI论文3篇；申请人均为通讯作者。2021年获得广东省科技进步奖二等奖（排名第2）。