b'Downy mildew causes problems for spinach growers across the globe. University of Arkansas researchers are leading a multidisciplinary group of scientists working to increase spinachs resistance to the disease. Breeding Better SpinachIn a new USDA study, researchers are working to find disease resistance at the molecular level.Katie PrattUNIVERSITY OF ARKANSASscientists are researchingWith spinach costing around $5,000 an acre to plant, it can ways to increase disease resistance in a superfood that isbe economically devastating if growers have to terminate a growing in popularity in American diets.field due to diseases. The largest spinach-producing states are Full of vitamins and minerals, spinach consumption hasCalifornia, Arizona and Texas. The majority of American spinach increased dramatically in the U.S. in recent years due to itsseed production occurs in the Pacific Northwest.inclusion in ready-made salad mixes available at grocery stores.Shi is the lead researcher on a four-year, $3.57 million U.S. However, it is also susceptible to a slew of diseases includingDepartment of Agriculture grant to help increase disease resist-Fusarium wilt, white rust and downy mildew. It also faces rela- ance in spinach. He will lead a group of multidisciplinary research-tively new disease pressures from Anthracnose leaf spot anders from several states as they try to find molecular pathways Stemphylium leaf spot. within spinachs genome that may help the plant fight diseases. Downy mildew is a disease that affects spinach productionThis grant will build upon and validate findings from Shis worldwide, says Ainong Shi, University of Arkansas (U of A)previous USDA-funded project that sought to develop ways associate professor. Fusarium wilt is one of the most importantfor spinach to move from conventional breeding into molecu-diseases affecting seed production. lar breeding. In that project, Shi screened cultivars for disease Like most foods produced for human consumption, spinachresistance, developed a genetic map for spinach and discovered production has very little room for error. genetic variations within spinach cultivars.The quality standards are very high for spinach produc- In the first project, we found some genetic variations that tion, says Jim Correll, U of A distinguished professor at thewe can use as bookmarks to look for areas within the spinach Department of Entomology and Plant Pathology. If diseasegenome that might hold keys to disease resistance, Shi said. damages as little as 3% to 4% of a field, it will make the entireWe still have a lot more bookmarks to develop and genetic pro-crop unmarketable. cesses to understand.44/ SEEDWORLD.COMFEBRUARY 2024'