ARS Scientists working to make wheat climate resilient
By Kay Shipman, FarmWeek
Agricultural Research Service (ARS) scientists found unanticipated, concerning wheat reactions to higher levels of carbon dioxide at the Mycotoxin Prevention and Applied Microbiology Research Unit in Peoria. However, advance awareness allows the search for solutions “to help feed people and keep food safe and healthy,” one of the lead researchers told FarmWeek.
William Hay, a plant physiologist, and Martha Vaughan, a supervisory molecular biologist, are leading experiments to evaluate wheat climate resilience at USDA’s National Center for Agricultural Utilization Research. Their goal is to preempt a worrisome response in wheat resistant to Fusarium head blight when grown in high carbon dioxide levels that are predicted for the end of the century.
In the lab’s growing chambers with high carbon dioxide levels, wheat varieties resistant to Fusarium head blight grew larger, increasing the risk of lodging, and dramatically increased amounts of starch and carbohydrate in the grain, decreasing grain protein and mineral levels. Results also suggest the loss of nutrients can raise the risk of mycotoxin contamination and threaten grain end-use quality. While the susceptible wheat varieties also grew taller in the growing chambers, they didn’t suffer the same impact on grain nutrient content.
“One of the key things that concerned us was one of the chief ways of protecting the crop against disease was selecting one these moderately resistant lines (to plant),” Hay said. “But now, you’re going to be losing some of that efficacy and nutrient content so it’s quite concerning. It was very unexpected. That was not a relationship that we had anticipated.”
In addition, the scientists tested the impact of higher carbon dioxide levels on 45 strains of Fusarium and found certain ones became more aggressive, Vaughan reported. The severity of blight and production of mycotoxins like deoxynivalenol, also known as vomitoxin, depends on the fungal strain and wheat variety attacked. With climate change, “there will be an evolution in pathogens as well,” Vaughan noted.
For now, wheat growers should continue selecting resistant varieties and apply fungicides at the right time to reduce the likelihood and severity of a Fusarium-head-blight outbreak, according to the two researchers. “With climate change, we can’t predict what will happen. Resistant lines may be less resistant, but they will still provide protection,” Vaughan said.
To help growers, a team of ARS researchers in Peoria has “identified bacteria and fungi microbes to combat the fusarium pathogen. We are hoping to get a patent out in two years,” Vaughan said.
At the same time, ARS scientists are working with wheat breeders from Minnesota, South Dakota and Vienna, Austria, to identify climate-resilient, Fusarium head-blight-resistant lines.
The Peoria team’s findings are helping to inform the wheat breeders’ efforts.
“Part of the reason we’re looking that far out (in the future) is because the length of time it takes to get a variety out and released can be up to a decade,” Hay said. “So, the more information we can get to wheat breeders ahead of time, the more they can make informed decisions on what varieties to look at and how they will perform in the future so they can make informed breeding decisions now.
“We are looking far into the future to tackle these problems before they become catastrophic for agriculture,” Hay said. “We have brilliant minds working on these problems, and we have enormous resources to try to find those (wheat) lines that will help to feed people and keep food safe and healthy.”
Vaughan agreed: “I am optimistic as well. I believe in the science, and we are collaborating with the best minds around the world.”