Generation of a promising universal RNAi vector system to control plant pests

Abstract

RNA interference has great potential value in plant pest control. We used existing plasmids and selected the conservative sequence of the chitinase (Chi) gene, which is highly homologous with many plant pests, to be the target sequence. The first step was to use conventional PCR technology to build the cloning vector pGr398 with two groups of isocaudomers. The target gene forward and reverse sequences were inserted into this carrier through the A-T connection. Then the cloning vector with the target fragment was connected to the vector pBI121 to obtain the RNAi vector. Finally, the two RNAi plant transformation vectors pGr320 (GFP) and pGr326 (Chi) were successfully constructed. These were used to verify the feasibility of the RNAi plant transformation vector system. Using this vector system, we imported two RNAi plant transformation vectors into Agrobacterium to obtain the transformation vector (G0 and G3). We successfully obtained transgenic tobacco lines using the Agrobacterium-mediated leaf disc method. By feeding tobacco to cotton bollworm larvae, we successfully reduced expression of the Chi gene in the larvae and achieved the RNAi effect to some extent, demonstrating the feasibility of our system. We successfully created a simple universal RNAi plant transformation vector system that can improve the construction efficiency of RNAi vectors and promote widespread use of RNAi technology in plants.