Transgenic tobacco expressing dsRNA of the arginine kinase gene exhibits enhanced resistance against Helicoverpa armigera

摘要

Helicoverpa armigera Hubner (cotton bollworm) affects commercial value crops and can cause major economic losses. The wide application of insecticides and Bacillus thuringiensis cotton (Bt-cotton) has led to the enhanced resistance of cotton bollworm along with insecticide pollution that affects food production and the environment. Transgenic plants that produce double-stranded RNA (dsRNA) to target insect genes are being developed as a pest control strategy. In this study, we used Agrobacterium-mediated transformation to produce transgenic tobacco plants expressing dsRNA to silence the H. armigera arginine kinase (H alpha AK) gene. Arginine kinase is a phosphotransferase that plays a critical role in cellular energy metabolism in invertebrates. Two different H alpha AK fragments, AK1 (containing the conserved domain) and AK2, were selected based on our previous experiment. When H. armigera second instar larvae were fed transgenic plants expressing H alpha AK1 and H alpha AK2 dsRNA for 2 days, H alpha AK transcript levels were significantly reduced by 86% and 74%, respectively. In addition, the ingestion of transgenic plants significantly delayed larval growth and development. An antifeedant bioassay showed that transgenic plant leaves had a significant antifeedant effect on H. armigera larvae based on the ecological interaction between the transgenic plants and the cotton bollworm. These results demonstrate the potential of plant-mediated RNAi for pest control.