Study suggests that most CBD-rich hemp plants are genetically 90 percent cannabis


Bethan Rose Jenkins, Cannabis News Writer/Editorial

Researchers from the University of Minnesota have published new findings pertaining to the genetics of CBD-rich plants. CBD (cannabidiol) is the primary non-psychoactive cannabinoid produced by cannabis and a variety of the Cannabis sativa plant species called “hemp”.

According to the study results, which were compiled in conjunction with hemp breeding company Sunrise Genetics, approximately 90 percent of a high-CBD plant’s genetics are derived from cannabis or “marijuana”, as opposed to hemp.

The entire study is featured in the recently-launched online academic journal New Phytologist.

Cannabis breeding techniques pose a risk for farmers, say researchers

Several different varieties of the cannabis plant were examined by the researchers, of whom were victorious in their attempts to assemble a complete genome from a new cannabis variety.

After breeding THC-rich cannabis plants with hemp varieties containing low traces of the psychoactive cannabinoid, the team discovered that they were able to develop completely new varieties laden with the medicinal compound CBD.

However, study co-author CJ Schwartz of Sunrise Genetics claims that this breeding technique “poses a challenge” for farmers.

“The genes that allow for the production of CBD are also a bit ‘leaky,’” Schwartz said. “This can result in about five percent of the product ending up as THC instead of 100 percent CBD.”

Cultivators who grow crops rich in the non-psychotropic cannabinoid CBD are more at risk of breaching the 0.3 percent THC limit; better known as a “hot” crop.

“These high-CBD plants are genetically [cannabis] for the most part and they can’t be expected to meet the legal definition of industrial hemp in every situation,” said study co-author George Weiblen, who is also a professor at the University of Minnesota.

“This means that CBD products – such as flowers, extracts and edibles – that are labeled ‘hemp’ could be incorrectly labeled and falsely branded. Fiber hemp and products made from hemp seeds, however, are drug-free.”

Study co-author developed cannabis genetics test alongside researchers last year

Just before 2020 came to an end, the cannabis industry was indulged with another incredible discovery. A few months back, study co-author Wieblen led a different group of researchers, who successfully managed to develop a genetics test capable of predicting whether or not a cannabis plant will produce an abundance of CBD or THC molecules.

Three different varieties of Cannabis sativa plants were analyzed for the study. Plant material was sourced from industrial hemp cultivators, as well as cannabis samples from the National Institute on Drug Abuse (NIDA) and native or feral “ditch weed”.

The genetic markers of cannabis were compared by researchers with the proportion of CBD to THC. Thanks to their findings, the team have stimulated a better overall understanding of the genetics of CBD and THC-dominant plants.

Consequently, this may assist the U.S. Department of Agriculture and state agriculture departments in determining specific varieties that could essentially steer farmers’ planting choices, not to mention the quality and consistency of hemp plants.

“We hope this new test can assist in new seed certification for the hemp industry,” Weiblen said. “For hemp to take off in Minnesota and elsewhere, there must be ways to assure growers they won’t have to destroy their crops at the end of the season.”

You can read the entire study in the American Journal of Botany.