The approach of a deadly crop disease may be hastened by the remnants of Hurricane Dennis, which is just grazing Iowa with its dissipating winds today. Forecasters say that wind could carry spores of the disease called soybean rust. Martijn van de Mortel is a post-graduate researcher at Iowa State University who just returned from studying soybean rust in Brazil. He says so far the disease hasn’t cost Iowa farmers much of their crop but that will change. Under severe conditions they could see 70 to 80-percent yield loss. With Iowa the biggest producer of soybeans, he says that’s important, “Could be very big numbers.” The crop disease was discovered a century ago in Japan and its advance to the western hemisphere was slow. Less than five years ago it was found in Central and South America. Weather helped the fungus to travel last fall, as he says tropical storms including Ivan transported some of the spores into the southeastern United States. Moretel brought back cell material from Brazilian soybean plants, including some that appear to resist the disease. He’ll use I-S-U’s “gene chip” technology to map the genetic matter of the bean plants and figure out how all their genes are “expressed” and what parts might fight the disease. He says they’re not just on-and-off switches, either, but more like “dimmer switches.” By analyzing the 30-thousand genes in each healthy or infected plant he hopes to determine which genes in each are turned on or off, a lot or a little. Few soybean plants can resist the rust fungus, but Mortel says he found some that have at least some defense mechanisms, and that’s where they’ll begin.