Tuesday, May 19, 2015

New soybeans resistant to soybean rust, soybean cyst nematode, and more!

Most crops have some sort of insect or disease pressure which growers have to face year after year.  The most common way for a grower to combat yield loss to insects and disease is to use some sort of pesticide.  Breeders, however, try to make crops resistant to insects and disease, reducing the yield loss and cost of inputs.  Breeders will work on crops for years to ensure that not only does it have the traits that they want to put into the crop, but also will have everything that current popular varieties express (i.e., high nutrient content, predictable growth, high yield, etc.) and that they haven't added any undesirable traits.

soybean rust (Phakopsora pachyrhizi) by Daren Mueller, Iowa State University, Bugwood.org

Researchers have known for years that certain wild relatives of commercial soybean have genes which impart resistance to diseases.  However, they have been unsuccessful at cross-breeding the plants since 1979 and it was thought impossible for them to produce reproductive plants.  But by exposing the hybrid's aborted, immature seeds to a hormone treatment, the seeds matured and the plants were able to be grown and bred.  Many generations of crossing the hybrids with the 'Dwight' soybean cultivar until only the desirable disease resistance traits were retained from the wild parent.  The new lines are resistant to soybean rust, soybean cyst nematode, or phytophthera root rot and some even have higher yield or protein content too.  These new genes will be able to add many new traits to existing breeding programs.

Source Article: Plant breeder boosts soybean diversity, develops soybean rust-resistant plant