By Krisy Gashler, Courtesy of The Cornell Chronicle
As the hemp industry grows, producers face the challenge of cultivating a crop that has received comparatively little scientific study, and that can become unusable – and illegal – if it develops too much of the psychoactive chemical THC.
In a new study, Cornell researchers have determined that a hemp plant’s propensity to “go hot” – become too high in THC – is determined by genetics, not as a stress response to growing conditions, contrary to popular belief.
“Often that issue of going hot has been blamed on environment,” said Larry Smart, Ph.D., senior author of the study and professor in the horticulture section of the School of Integrative Plant Science.
“[People thought] there was something about how the farmer grew the plant, something about the soil, the weather got too hot, his field was droughted, something went wrong with the growing conditions,” Smart said. “But evidence from this paper is that fields go hot because of genetics, not because of environmental conditions.”
The study, “Development and Validation of Genetic Markers for Sex and Cannabinoid Chemotype in Cannabis Sativa L” was published Jan. 10, 2020, in Global Change Biology-Bioenergy.
Read the full article here.\

Horticulture professor Larry Smart, Ph.D., who leads Cornell University’s hemp research program, examines industrial hemp plants growing in a greenhouse laboratory at Cornell AgriTech in Geneva, NY.