水稻OsLecRK1基因介导的抗褐飞虱功能分析

褐飞虱Nilaparvata lugens St(a)l是对水稻最具破坏性的害虫之一,OsLecRK1是水稻Bph3基因簇中对褐飞虱抗性贡献最大的基因.本文对RHTd(含Bph3)等材料进行了褐飞虱抗性评价,克隆并构建了OsLecRK1过量表达突变体水稻,利用该突变体分析了OsLecRK1基因对褐飞虱若虫存活率、若虫发育历期等生物学参数的影响.结果 表明,含Bph3基因水稻RHTd对褐飞虱的抗性明显地强于含Bph1基因水稻Mudgo和bph2基因水稻ASD7,RHTd水稻的褐飞虱受害指数仅为Mudgo和ASD7水稻的53.5％和24.1％.过量表达OsLecRK1基因能显著地增加水稻对褐飞虱的驱避性和抗生性,褐飞虱雌成虫偏好于在野生型水稻上产卵;突变体水稻上的褐飞虱若虫存活率显著地降低,仅为野生型水稻上若虫存活率的75.2％ ～81.8％,且若虫发育历期显著地延长,羽化率和初羽化雌成虫体重均显著地降低;此外,褐飞虱在突变体水稻上取食分泌的蜜露量只有野生型上的40.3％ ～ 60.9％,褐飞虱单雌产卵量只为野生型51％ ～61.2％,卵孵化率只有野生型的52.2％～56.7％,均显著地减少.结果 表明,含Bph3基因水稻RHTd对褐飞虱的抗性明显地高于分别含Bph1、bph2的水稻Mudgo和ASD7;水稻Bph3基因座的OsLecRK1单个基因过量表达即可显著增加水稻对褐飞虱的抗性,OsLecRK1协同影响褐飞虱的多个生物学参数降低褐飞虱的适合度.

Functional analysis of rice OsLecRK1 in resistance to rice brown planthopper

Rice brown planthopper Nilaparvata lugens Stal is one of the most destructive pests to rice. OsLecRK1 is the most resistant gene among the four resistance genes of Bph3 locus. In this paper, the resistance of RHTd (containning Bph3) and other rice materials to brown planthopper were evaluated, and the effect of rice OsLecRK1 gene on nymph survival rate, nymphal development period and other biological parameters of brown planthopper was analyzed using OsLecRK1 overexpressing rice mutants. The results showed that the resistance of RHTd with Bph3 gene to BPH was significantly higher than that of Mudgo with Bph1 gene and ASD7 with bph2 gene. The damage index of brown planthopper of RHTd was only 53.5% and 24.1% of that in Mudgo and ASD7 respectively. Overexpression of OsLecRK1 gene in rice can significantly increase the repellency and antibiosis of rice to BPH. Female adults of BPH preferred to feed and lay eggs on wild-type rice compared to on mutants. The survival rate of BPH nymphs on mutant rice plants was significantly reduced, only 75.2%~81.8% of that on wild-type rice. The developmental period of nymphs was significantly prolonged, and the emergence rate and newly emerged BPH female adults were significantly decreased. In addition, the amount of honeydew secreted by BPH on mutant rice plants was only 40.3%~60.9% of these on the wild type, the number of eggs per BPH female adult was only 51.0%~61.2% of that on the wild type, and the hatchability of eggs was only 52.2%~56.7% of that on the wild type. It indicated that the resistance of rice RHTd containing Bph3 gene to BPH was significantly higher than that of Mudgo and ASD7 containing Bph1 and bph2 gene respectively, only overexpression OsLecRK1 of Bph3 locus could significantly increase rice resistance to BPH, and OsLecRK1 reduced the fitness of BPH by regulating multiple biological parameters of BPH.