ARS | Publication request: Integration of DNA markers with chromosome engineering for efficient introgression of resistance genes from wild grasses into wheat

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: February 16, 2012
Publication Date: April 1, 2012
Citation: Xu, S.S., Niu, Z., Klindworth, D.L., Chao, S., Friesen, T.L., Faris, J.D., Jin, Y., Cai, X., Harris, M.O. 2012. Integration of DNA markers with chromosome engineering for efficient introgression of resistance genes from wild grasses into wheat. Meeting Abstract. pg 15.

Technical Abstract: Wheat is one of the major food crops and its production is constantly threatened by numerous diseases and insects. Many wild grasses related to wheat possess potent resistance genes and represent a valuable genetic resource for wheat improvement, especially for disease and insect resistance. However, introgression of resistance genes from wild grasses into wheat has been a challenging task due to inherent difficulty and low efficiency in inducing and recovering homoeologous recombinants through classical chromosome engineering. An efficient procedure for alien gene introgression is essential for utilization of resistance genes from the wheat-grasses. In an effort to utilize wild species-derived resistance genes effective against Ug99 stem rust races, a serious threat to global wheat production, we developed a highly efficient scheme of chromosome engineering for introgression of resistance genes derived from wild grasses. In this procedure, we first developed a large backcross population of ph1b-induced homoeologous recombinants and then identified the recombinants carrying the gene of interest on small interstitial segments using robust DNA markers and high-throughput phenotyping and genotyping. By using this procedure, we developed wheat germplasm carrying four Ug99-resistant genes on minimal alien chromatin in a short period of time. We are currently applying this procedure to transfer more genes for resistance to stem rust, leaf rust and Hessian fly, from wild grasses into the wheat genome. This study demonstrated that integration of modern genomic and marker technology by classical chromosome engineering and breeding greatly improved the efficiency for transferring resistance genes from wild relatives into modern crops.