By Jamie Martin
Researchers have made a new discovery showing that rice plants can naturally trap and kill fall armyworm caterpillars, one of the most damaging agricultural pests.
The study was conducted by scientists from the Arkansas Agricultural Experiment Station, led by Devi Balakrishnan with guidance from Rupesh Kariyat. Their research, published in Ecological Processes, explains how rice plants use their own structures to protect themselves.
During the flowering stage, rice spikelets are open to allow pollination. At this stage, they produce a light scent that attracts caterpillars. When the insects move toward the floret, they become trapped by tiny hair-like structures called trichomes.
“This was not in the plan,” said Balakrishnan, Ph.D., in the department of entomology and plant pathology for the Arkansas Agricultural Experiment Station, the research arm of the University of Arkansas Division of Agriculture. “I was doing another experiment on rice with fall armyworms and started noticing these caterpillars were inside the spikelet, and they were dead.”
As the spikelet slowly closes, the caterpillars are unable to escape and eventually die. The study found that nearly 50% of young caterpillars were caught and killed in this way within 48 hours.
The researchers also observed that caterpillars showed more interest in flowering spikelets compared to older plant stages. This suggests that the scent plays a key role in attracting pests.
This natural trapping system acts as a defense mechanism, helping rice plants protect their grains from insect damage. The discovery provides new insight into plant-insect interactions.
Scientists believe this process can be used to develop safer pest control methods. For example, enhancing the scent released by rice plants could attract more pests into these traps, reducing reliance on chemical pesticides.
“The running joke in our lab is that no matter what you’re studying — even protein kinases — at some point you’ll be counting trichomes,” said Rupesh Kariyat, an associate professor of crop entomology, served as Devi Balakrishnan's adviser for the study. “This just reminded us that sometimes the most interesting science starts when something doesn’t go according to plan.”
With fall armyworm spreading globally and becoming resistant to insecticides, this finding is especially important for farmers. It offers a sustainable and environmentally friendly option to protect crops.
Overall, the research highlights how natural plant defenses can support future farming practices and improve crop protection strategies.
Photo Credit: istock-pkujiahe
Categories: National