In a recent study at Cornell University, researchers have uncovered a potential agricultural breakthrough: cannabinoids found in hemp could serve as the basis for natural pesticides.
The study, led by Larry Smart, a plant breeder and professor at the School of Integrative Plant Science in the College of Agriculture and Life Sciences from Cornell AgriTech, highlights the defensive properties of cannabinoids against herbivores, opening new possibilities for sustainable pest control in agriculture.
The defensive role of cannabinoids
For decades, cannabinoids, including CBD and THC, have been studied primarily for their medical and psychoactive effects. Recent research at Cornell suggests that these compounds may play a crucial role as “defensive compounds” in plants, protecting them from ultraviolet rays, pathogens and herbivores.
Larry Smart notes, “They have been assumed to be defensive compounds because they accumulate primarily in female flowers to protect seeds, which is a fairly common concept in plants.”
Cornell’s hemp breeding program, launched in 2017, provided a platform for this groundbreaking discovery. Different hemp cultivars have been evaluated for their susceptibility to pests, with varieties lacking cannabinoids experiencing significant insect damage. Conversely, strains containing cannabinoids, such as CBDA and CBGA, suffered significantly less damage from pests such as the Japanese beetle.
Experimental and future perspectives
Controlled laboratory feeding studies isolated CBDA and CBGA, the precursor compounds of CBD and CBG, respectively. The researchers observed that as cannabinoid concentration increased, insect larvae showed reduced growth and lower survival rates.
George Stack, a postdoctoral researcher who participated in the study, explains the importance of these results: “The study gives us insight into how cannabinoids function in natural systems and can help us develop new hemp cultivars. compliant with THC that maintain these built-in natural defenses against herbivores.”
Although the potential use of cannabinoids as pesticides is exciting, there remain challenges. The study highlights the need for further research to identify the specific parasites against which cannabinoids are effective. Regulatory barriers, which arise from the pharmacological effects of these compounds, also pose obstacles to their widespread adoption in agriculture.
Future research will aim to explore the impact of cannabinoids on sap-sucking insects, such as aphids, and assess whether other cannabinoid-producing plant species share similar insecticidal properties. Researchers are particularly intrigued by the concept of convergent evolution, according to which the same adaptation appears independently in different species.
