Optimizing RNA interference for insect pest control

RNAi is an advanced specific post-transcriptional gene silencing method; its discovery in the nematode Caenorhabditis elegans resulted in the Nobel Prize in Physiology and Medicine in 2006, illustrating its wide scientific impact. During the first RNAi decade, scientists also recognized its potential for useful applications, including crop protection. Especially the fact that RNAi may specifically target certain pest insects without causing toxicity for non-target organisms is highly attractive. Although some promising results demonstrating the use of RNAi in crop protection have already been realized, important challenges, such as the variable efficiency in different insects, should be addressed before RNAi can be employed as a control strategy against a broad range of pest insects. Possible causal factors of variability are degradation of dsRNA in the insect body and the efficiency of dsRNA delivery and uptake systems. This project has 3 main objectives: 1) to develop new dsRNA delivery methods to overcome limitations that are observed today in RNAi by feeding; 2) to investigate factors that play a role in RNAi efficiency and so to maximize toxic effects; 3) to investigate RNAi specificity as well as to define conditions for dsRNA design that are necessary for strong insect selectivity. More knowledge on these topics and especially a more efficient delivery of dsRNA will lead to new or improved techniques of RNAi-based pest control.