At Iowa State University, Seed Physiology Ph.D. student Amina Moro is advancing research that could reshape how farmers balance productivity with environmental sustainability. Her work explores how corn responds to nearby perennial groundcover, an emerging system designed to protect soil year-round, offering new insights into how crops perceive and react to competition even before it begins.
Published in the Journal of Agronomy as Spatial Proximity to Perennial Groundcover Triggers Shade Avoidance Responses in Corn, Amina’s work focuses on how corn responds to nearby perennial groundcover (PGC), a system gaining attention for its ability to protect soil year-round.
“Perennial groundcover systems are very promising because they keep the soil covered year-round, improving soil health, reducing erosion, and enhancing sustainability,” Amina explains. “But farmers are hesitant to adopt them because of concerns about competition with corn, especially early in the season.”
Her research challenges a common assumption, that competition between plants begins only when they compete for water or nutrients. Instead, she found that competition may start much earlier, through light signals that plants use to detect nearby neighbors.
At the center of Amina’s study is a concept called shade avoidance response (SAR). In simple terms, plants can “sense” when other plants are nearby even before they are physically shaded.
“When corn detects changes in light quality, it interprets it as a sign that competition is approaching,” Amina says. “It responds by growing taller and reallocating energy toward vertical growth.”
While this might sound beneficial, it comes at a cost. Taller plants often develop thinner stems and reduced structural strength, which can lead to lodging and reduced efficiency later in the season.
One of the most significant findings from Amina’s study is that proximity, not just the presence of groundcover, determines how corn responds.
“We observed that corn begins to respond at very short distances,” she says. “At 6 centimeters, plants already initiated a shade avoidance response, but at 25 centimeters, they behaved as if there were no competition.”
Even more striking, when corn was in direct contact with groundcover, the stress reduced growth entirely.
This insight has important implications for how cropping systems are designed. Rather than eliminating groundcover, farmers may simply need to adjust spacing.
According to Amina’s advisor, Seed Physiology Professor Dr. Susana Goggi, this research addresses one of the most pressing challenges in modern agriculture: balancing soil health with crop productivity.
“The use of perennial groundcover is a game-changer,” Goggi explains. “It can reduce soil erosion, water runoff, and nutrient loss. But it also creates microclimatic changes that can affect crop growth.”
Amina’s work is helping identify the “sweet spot,” the ideal distance between crops and groundcover that preserves environmental benefits without sacrificing yield.
The practical applications of this research are clear. By maintaining a small buffer zone, around 25 centimeters, farmers can prevent early stress signals in corn while still benefiting from soil protection.
Amina’s findings also highlight the importance of hybrid selection. Some corn varieties are more sensitive to shade signals than others, meaning farmers can further optimize performance by choosing the right genetics.
“Farmers do not have to choose between improving soil health and maintaining yield,” Amina says. “With the right combination of spacing, hybrid selection, and management practices, it is possible to design systems where corn grows efficiently while the soil remains protected.”
Amina’s journey to this moment began thousands of miles away in Ghana. Originally arriving at Iowa State to pursue a master’s degree, her passion for research and rapid growth as a scientist led her to pursue a Ph.D. program. Today, she is part of a multidisciplinary research team exploring innovative cropping systems that could transform agriculture
For Dr. Goggi, mentoring Amina has been a rewarding experience.
“She quickly adapted to working in a multidisciplinary research team and became an essential member,” Goggi says. “She has grown into an independent thinker and a dedicated researcher. I am thrilled she now has her first peer-reviewed publication.”
From her first journey from Ghana to becoming a published scientist, Amina’s story is one of determination, curiosity, and impact.
As agriculture continues to shift toward more sustainable and climate-resilient systems, researchers like Amina Moro are helping lead the way, one discovery at a time.
