Throughout history, plant diseases have had devastating impacts on human lifestyle leading to starvation and immigration. Thanks to the work of plant breeders, many diseases, like stem rust in wheat, which once devastated South Dakota’s wheat growers, is controlled today, says Bob Fanning, SDSU Extension Plant Pathology Field Specialist.
“Of all the characteristics wheat producers consider when selecting which wheat variety to plant, stem rust resistance is the one today’s wheat producers don’t worry much about. The reason is simple; virtually all public and private wheat breeding programs place a high priority on stem rust resistance, and they don’t release varieties without a minimum level of resistance to the devastating disease,” Fanning said.
He adds that although today’s gene pool of high-yielding wheat germplasm resistant to stem rust is quite large, this wasn’t always the case.
Edgar McFadden ?
For a brief period of time in the late 1800s Dakota Territory, wheat acreage increased from just over 100,000 acres to well over 1 million acres.
“In 1897, at its peak, it has been stated that two-thirds of the world’s wheat was shipped from present-day Eureka. Wagons bearing the crop rolled in from as far as 75 miles away,” Fanning said.
Stem rust quickly put a stop to wheat’s rapid growth in South Dakota, says Fanning.
“In 1904 an epidemic of stem rust reduced South Dakota’s wheat production by 50 percent. For the next several decades, planted wheat acres were high, but rusts and scab plagued wheat farmers, nearly wiping out the crop in 1920,” he said. “Wheat farmers across the world were experiencing similar challenges, causing poverty and hunger.”
It was during this time that Fanning says, Edgar McFadden was coming of age. Born in 1891 near Webster, McFadden was 20 years of age, when he watched the 1911 wheat crop reduced from 40 bushel an acre potential to 5 bushels an acre because of stem rust.
“At the same time, he noticed that the rust hadn’t bothered a patch of ‘Yaroslav emmer,’ an ancient grain crop,’” Fanning said. “When he enrolled in the Dakota Agricultural College, now South Dakota State University, that fall, he wondered if ‘emmer’ crossed with wheat would provide rust resistance in the progeny.”
In short, Fanning says McFadden successfully crossed “emmer” and the spring wheat variety, “Marquis,” to eventually produce the variety, “Hope,” which was resistant to both stem and leaf rusts.
“Magazines of the 1940’s reported that perhaps 25 million people across the world escaped death by starvation due to bread derived from McFadden’s rust resistant wheat, “Hope,’” said Fanning.
Many of today’s wheat varieties have Hope as a great-grandparent.