Crops: Easy Transfer of Disease-Resistance Genes

A global alliance of researchers has pioneered a new method to rapidly recruit disease-resistance genes from wild plants for transfer into domestic crops. The technique promises to revolutionize the development of disease-resistant varieties for the global food supply. The technique called AgRenSeq was developed by scientists at the John Innes Centre in Britain working with colleagues in Australia and the US. It was published today in Nature Biotechnology. The result speeds up the fight against pathogens that threaten global food crops, including wheat, soyabean, maize, rice and potato, which form the vast bulk of cereals in the human diet. Professor Harbans Bariana from the Sydney Institute of Agriculture and the School of Life and Environmental Sciences is a global expert in cereal rust genetics and a co-author of the paper. He said: "This technology will underpin fast-tracked discovery and characterization of new sources of disease resistance in plants." The current research builds on previous collaborative work done by Professor Bariana with the CSIRO and John Innes Centre. It used two wheat genes cloned by this international team as controls and Professor Bariana conducted the phenotype assessments for the study. AgRenSeq lets researchers search a library of resistance genes discovered in wild relatives of modern crops so they can rapidly identify sequences associated with disease fighting capability. From there researchers can use laboratory techniques to clone the genes and introduce them into elite varieties of domestic crops to protect them against pathogens and pests such as rusts, powdery mildew and Hessian fly. Dr Brande Wulff, a crop genetics project leader at the John Innes Centre and a lead author of the study, said: "We have found a way to scan the genome of a wild relative of a crop plant and pick out the resistance genes we need: and we can do it in record time. This used to be a process that took 10 or 15 years and was like searching for a needle in a haystack. "We have perfected the method so that we can clone these genes in a matter of months and for just thousands of dollars instead of millions." The research reveals that AgRenSeq has been successfully trialed in a wild relative of wheat -- with researchers identifying and cloning four resistance genes for the devastating stem rust pathogen in the space of months. This process would easily take a decade using conventional means.

Source: Agriculture and Food News, ScienceDaily. www.sciencedaily.com