P-199 - Engineering a super wheat with triple rust resistance

Wheat rust is one of the most serious diseases affecting wheat globally. Recent advances in genome sequencing and cloning technologies have enabled the cloning of several resistance genes against stem, stripe, and leaf rust from wheat and its wild relatives. Previous research involving transgenic wheat that overexpresses rust resistance genes highlighted the importance of generating lines that express multiple resistance genes for long-term, durable rust resistance. Therefore, we aimed to engineer a wheat line with triple rust resistance. We selected a stack of five genes for each type of rust (stem, leaf, and stripe) resistance based on their performance around the world, and cloned them into an in-planta expression vector using Golden Gate. We also utilized Cre-Lox recombinase technology, which allows for heat-shock-mediated post-transformation excision of the selectable marker and GRF-GIF morphogene segments from the wheat genome. We outline various strategies by following both untargeted and targeted approaches,  aiming to integrate each rust stack in close genetic proximity, thus ensuring their subsequent inheritance as a monogenic trait. Consequently, the final product can be used in breeding programs to transfer triple rust resistance into elite cultivars. Deploying triple rust-resistant wheat varieties will enhance economic and sustainable wheat production while also reducing the environmental harm caused by chemical use in agricultural practices.