Soybean Rust: Will Resistance Work?
The Asian soybean rust, Phakopsora pachyrhizi , was first found in the U.S. in Hawaii in 1994. After 1994, the pathogen was discovered in two countries in Africa and three countries in South America. The pathogen has been known to occur in Asia and Australia for over 50 years and many countries have reported drastic yield reductions in Asia. The rapid spread of P pachyrhizi and the potential for severe yield losses makes this the most destructive foliar disease of soybean. Soybean rust, if introduced into the U.S., could have a major impact on both total soybean production and production costs in the U.S. The focus of this presentation is on soybean rust resistance. I will review some historical aspects of the research on host resistance. This will include introducing and defining some terminology like specific resistance, races of the fungus, partial resistance, and yield stability. I will follow this historical perspective with what is known today in terms of current projects on host resistance research and what potential scenarios might occur for future research and the development of resistance. I also will briefly talk about the fungus in terms of its host range.