Developing a system that integrates cash crops with a cover crop needed to be planted just once every five to 15 years is a tall order. But it’s one researchers at Iowa State University suggest can be realized. They’re working on a project titled Regenerating America’s Working Landscapes to Enhance Natural Resources and Public Goods through Perennial Groundcover.
“We want to develop groundcover systems where a perennial cover crop is planted once and then persists for multiple years alongside annual crops,” said Raj Raman, a professor of agricultural and biosystems engineering at Iowa State University. “The cover crops would be alive during the six months to nine months when fields are often bare between harvest and planting, yet would pose little or no competition to the cash crops.
“If we’re successful, we believe this could encourage more widespread adoption of cover crops to reduce the unintended consequences of conventional-cropping systems in a way that’s convenient and low-cost for farmers.”
Perennial groundcover would protect and enhance soil, reduce nutrient export into water and enhance carbon-sequestration potential. There could be some weed- or insect-suppression effects, leading to reduced need for herbicides or insecticides, Raman said.
There might also be other advantages. For example there were anecdotal reports in 2020 that corn growing in perennial test plots withstood stronger winds than corn in adjacent, conventional plots. Researchers hypothesized that the corn’s reduced “lodging” in the plots could be due to improved soil health that led the corn to develop stronger roots.
Experiments led by Kenneth Moore and Shui-zhang Fei set the stage. Moore, a professor in agriculture and life sciences, and Fei, a professor of grass genetics and breeding in horticulture, have tested more than 30 perennial species for compatibility. They found that some perennials grew and provided ecosystem benefits without sacrificing crop yields – but only under ideal circumstances.
The research group’s primary goal now is to find perennials that will work reliably in the varied conditions farmers face in multiple years.
- Will the cover crop candidate survive through multiple seasons yet go dormant in time for corn or soybean planting?
- If the perennial doesn’t go dormant at the right time, what will it take to suppress so it won’t compete with primary crops during the growing season?
- If the perennial works in field conditions in Iowa, what about drier climates in Nebraska or Kansas, or colder temperatures in Wisconsin?
The team is conducting field research and computer modeling, backed by a five-year, $10 million grant from the U.S. Department of Agriculture’s National Institute of Food and Agriculture.
About a dozen other Iowa State faculty, staff and graduate students are working on the new project along with counterparts at universities in Kansas, Kentucky, Missouri and Wisconsin. Other research and commercialization partners come from The Land Institute and Corteva Agriscience.
The team expects to narrow the list of perennial species worth studying. Main candidates currently include varieties of Kentucky bluegrass and a species called Poa bulbosa, which goes dormant based on day length.
Source: agupdate.com
Photo Credit: gettyimages-mvburling
Categories: Iowa, Crops, Corn, Soybeans