Morphological, Genetic, and Secondary Metabolomic Analysis of Mutant Cannabis

Hops (Humulus lupulus) and Cannabis sativa L., both belonging to the Cannabaceae family, share a botanical relationship and a history of human use. Hops, known for their aromatic properties, are essential in beer brewing, whereas Cannabis sativa L. is valued for its medicinal, recreational, and industrial applications due to its varied chemical composition. Despite historical attempts at cross-breeding and grafting between hops and Cannabis, successful hybridization has not been documented, primarily due to genetic and biological constraints. This study investigates four off- spring from the grafting of Cannabis sativa L. onto Humulus japonicus, reputed within Cannabis breeding circles for their distinctive phenotypic traits. Our examination covers their morphological, phytochemical, and genetic aspects. While these plants exhibit unique morphological and growth characteristics compared to their parent species, genetic analyses reveal a purely Cannabis genome, conclusively negating any hybridization. We hypothesize that the grafting of these two dissimilar species may induce a mutagenic stress response, resulting in the unique phenotypic characteristics of the offspring. These findings highlight the unique outcomes of grafting between these two species, pointing to the potential for creating novel Cannabis varieties through unconventional breeding techniques.