Bulletin on Narcotics, Vol. XXX, No. 1
Jocelyn C. Turner, John K. Hemphill & Paul G. Mahlberg
Department of Biology, Indiana University, Bloomington, Indiana 47401
Keywords: Cannabis sativa, Cannabaceae, Cannabinoid, Individual Glands, Trichome
Glandular trichomes covering the plant surface have been implicated as the source at cannabinoids in Cannabis sativa L (DePasquale, 1974: Malingré et al., 1975). Hammond and Mahlberg (1973, 1977), in their scanning electron microscope study of these trichomes, described three gland types: the bulbous gland which possesses a very short stalk and a small head, the capitate-sessile gland which has a . large globular and multi-cellular head, and the capitate-stalked gland which consists of a large multi-cellular head, that terminates a stalk of variable height. Non-glandular trichomes are also present in abundance on the plant epidermis (Ledbetter and Krikorian, 1975). Fairbairn (1972) reported the presence of cannabinoids in both capitate-sessile and capitate-stalked glands and indicated that capitate-stalked glands were the major cannabinoid containing glands. DePasquale (1974), in an ultrastructural-study of the capitate-stalked glands, interpreted the secretory .Part of the gland to be a combination of the gland head and perhaps· apical stalk cells. Malingré et al. (1975) concluded that cannabinoids were present mainly in the epidermal glands and not in the mesophyll cells or non-glandular trichomes, although there was some indication of cannabinoid content in the leaf mid-rib.
The purpose of this investigation is to determine whether a correlation exists between glandular trichomes and cannabinoid content in cannabis. If specific glands are associated with cannabinoid content, a correlation should exist between the gland number present on a particular plant part and the cannabinoid content of that part. Furthermore, it should also be possible to establish a correlation between the numbers of each gland type and cannabinoid content.