Cornell University researchers have found cannabinoids could form the basis of effective pesticides.
There’s been significant research into cannabinoids in relation to their medicinal and intoxicating effects when consumed by humans. But why do cannabis plants produce cannabinoids? Its been thought these compounds help to protect the plants from various critters looking for an easy meal.
New research backs this school of thought; with Cornell University research indicating higher cannabinoid concentrations in hemp leaves results in proportionately less damage from insect larvae.
“It has been speculated that they are defensive compounds, because they primarily accumulate in female flowers to protect seeds, which is a fairly common concept in plants,” said Professor Larry Smart from Cornell’s School of Integrative Plant Sciences, who was senior author of the study. “But no one has put together a comprehensive set of experimental results to show a direct relationship between the accumulation of these cannabinoids and their harmful effects on insects.
The study involved hemp plants with varying concentrations of cannabinoids. In the absence of cannabinoids the researchers saw heavy damage from cabbage looper larvae, but in the presence of cannabinoids, much less.
The image above shows a CBD (cannabidiol) dominant individual adjacent to an insect-ravaged “cannabinoid-free” plant. THC (tetrahydrocannabinol) as a pesticide was not tested during this study due to federal laws. THC is the cannabinoid that has an intoxicating effect on humans.
“The potential use of cannabinoids as a pesticide is an exciting area for future research, but there will certainly be regulatory barriers due to pharmacological activity of the compounds, and more studies are needed to understand what pests cannabinoids will be effective against, said Professor Smart.
Results of the research have been published in the journal Horticultural Research.
This isn’t the first study to indicate cannabinoids have potential as pesticides. A study published in 2019 found:
“The naturally occurring CBD in Cannabis primarily acts as a feeding deterrent against pests. Consequently, cannabidiol ingested effectively inhibits the larval growth and development, resulting in high mortality.”
But the presence of cannabinoids doesn’t mean these cannabis plants are impervious to all insect damage – there are plenty of hemp pests; some of which can wreak havoc on the crop.