Nav: Home

Corn with a cover of grass

April 26, 2017

The phrase "a double-edged sword" describes something that is beneficial in some ways but problematic in others. One example is removing maize stover (the husks, stems and leaves of corn plants) from fields. Maize stover is used to make cellulosic ethanol, a renewable biofuel. And renewable biofuels are beneficial to the environment. However, removing the stover can harm the environment because it can cause the soil to erode and lose nutrients.

Taking up this double-edged sword is Cynthia Bartel, a doctoral candidate at Iowa State University. She's finding a way to lessen the harm and increase the benefits of removing maize stover.

"While water and wind erosion are substantial problems for maize stover removal, soil quality preservation is an even greater constraint," she explained. Bartel needed to find a way to remove the stover but preserve the soil quality. So, she turned to previous research for ideas and found that cover or companion crops can improve soil quality. Bartel liked the idea of using cover crops, but was curious about a different type of cover crop.

Instead of annual cover crops, which must be replanted every year, Bartel continued research at Iowa State University (ISU) involving perennial groundcover, and specifically grasses. "We envision that perennial grass seed might need to be purchased and planted only every four to five years, which would greatly reduce expenses compared to annual covers." Using a perennial groundcover could be a win-win, including natural resources preservation in addition to reducing costs. However, Bartel needed to determine if perennial groundcover and maize are compatible. She also needed to determine if using a perennial groundcover crop is both environmentally and economically beneficial.

To explore these questions, the ISU team conducted a field study at two locations in Iowa. In some areas, they planted Kentucky bluegrass with the maize. In other areas, they planted creeping red fescue with the maize. The team closely monitored and analyzed the crops over two years. "The success of the system largely depends on using a compatible species," she explained. And compatibility depends on several factors.

A compatible grass would easily and reliably grow in the area where it is planted. But, it would go dormant in the summer during corn's growing season. The team discovered that the older grass varieties originally selected for the project failed to establish. In addition, the modern grass varieties stayed green too long. Not finding a perfect match on the first try didn't deter the researchers though. "We identified key challenges in varietal selection to ensure that further research efforts are focused effectively," Bartel explained.

In addition to compatibility, Bartel studied the grasses' impacts on the maize. She found that the maize crops did produce less grain in the first year. However, in the second year, the normal control maize and the maize with grass had similar yields. Plus, the grass didn't negatively impact the quality of the stover in the second year or the quantity of the stover in either year. "Ultimately, there may be some yield penalty for perennial grass establishment in exchange for the natural resources benefits," Bartel concluded. "But refining the system further, to ensure compatibility between the row crop and grass cover species, should largely minimize that penalty."

Bartel's field study began exploring one possible way to lessen the harm and increase the benefits of removing maize stover. Now future research can build on her work.

Read more about Bartel's work in Agronomy Journal.
-end-


American Society of Agronomy

Related Maize Articles:

Detailed new genome for maize shows the plant has deep resources for continued adaptation
A much more detailed reference genome for maize is published in Nature today.
Corn with a cover of grass
Corn raised for biofuel can result in eroded soils, as all materials are removed from the field.
Geography and culture may shape Latin American and Caribbean maize
Variations in Latin American and Caribbean maize populations may be linked to anthropological events such as migration and agriculture, according to a study published April 12, 2017 in the open-access journal PLOS ONE by Claudia Bedoya from the International Maize and Wheat Improvement Center (CIMMYT) and colleagues.
New plant research leads to discovery of a gene that increases seed yield in maize
Researchers from VIB-UGent have discovered a gene that significantly increases plant growth and seed yield in maize.
Maize study finds genes that help crops adapt to change
A new study analyzed close to 4,500 maize varieties to identify more than 1,000 genes driving large-scale adaptation to the environment.
More Maize News and Maize Current Events

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Teaching For Better Humans
More than test scores or good grades — what do kids need to prepare them for the future? This hour, guest host Manoush Zomorodi and TED speakers explore how to help children grow into better humans, in and out of the classroom. Guests include educators Olympia Della Flora and Liz Kleinrock, psychologist Thomas Curran, and writer Jacqueline Woodson.
Now Playing: Science for the People

#535 Superior
Apologies for the delay getting this week's episode out! A technical glitch slowed us down, but all is once again well. This week, we look at the often troubling intertwining of science and race: its long history, its ability to persist even during periods of disrepute, and the current forms it takes as it resurfaces, leveraging the internet and nationalism to buoy itself. We speak with Angela Saini, independent journalist and author of the new book "Superior: The Return of Race Science", about where race science went and how it's coming back.