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Authors
- George Stack, Jacob Toth, Craig Carlson, Rebecca Wilk, Jamie Crawford, Ali Cala, Glenn Philippe, Joss Rose, Don Viands, Chris Smart, Larry Smart
- Mark Sisson, Wayne Lindsay, Mark Bridgen – Long Island Horticultural Research and Extension Center, Riverhead, NY
- Teresa Rusinek, Amy Hepworth, Peter Jentsch – Hudson Valley Research Lab and F.A.R.M., Highland, NY
Production of cannabinoids
Cannabidiol (CBD) is becoming very popular as a supplement for relief of seizures, pain, and anxiety. It is made in specialized leaf hairs on female floral tissue.
Choosing a cultivar for CBD production
There are no certified cultivars for CBD production and many of the currently available cultivars were derived from crosses between hemp and marijuana. It is critical to use a source of seed that is fully feminized (produced in a way that all the seeds are female), the population of plants from that seed lot is uniform, and the cultivar is stable for low THC production. Cuttings of selected female clones are also available, but it is not clear if production is better starting from seedling transplants or cutting transplants. We are demonstrating five cultivars in these trials: ‘Otto II’, ‘AC/DC’, ‘A2R4’, ‘T2’, and ‘TJ’s CBD’
Cultivars/lines in the 2019 HVRL and LIHREC demonstration trials
| Cultivar/Line | Company source | Cutting or Seed | % Germ | % Female |
| ‘AC/DC’ | Winterfox Farms, OR | Seed (Dioecious) | 97% | 49% |
| ‘Otto II’ | Winterfox Farms, OR | Seed (Dioecious) | 93% | 48% |
| ‘A2R4’ | Winterfox Farms, OR | Seed (Dioecious) | 68% | 52% |
| ‘T2’ | Boring Hemp, CO | Seed (Feminized) | 100% | ? |
| ‘TJ’s CBD’ | Stem Holdings, OR | Cuttings | N/A | N/A |
Locations and production methods
Plants were established from seeds or cuttings in 50-cell deep flats in early May in a greenhouse under 20 hour light. For dioecious lines (an equal mix of males and females), females were identified using DNA marker screening. Transplanting into raised beds with plastic mulch and drip irrigation was done on May 22 at LIHREC and June 3 at HVRL, with five plant plots of each cultivar in four replicated plots in a randomized design. Rows were spaced at 7 feet on center and plants spaced 4 feet within row for a planting density of 1,555 plants per acre. After transplant, the HVRL trial has been maintained using organic methods. LIHREC was fertilized with 150 pounds of elemental N-P-K broadcast pre-planting. Irrigation has been applied as needed.
Plant trait measurements
We are surveying several plant traits throughout the growing season including plant height, time to flowering, plant form and branching, pest and disease incidence, and floral development. There is significant variation for height, flowering time and form among the five cultivars. We have observed powdery mildew on some plants.
CBD and THC measurement and quality assessment
Female floral shoots will be sampled as plants approach harvest age to assess CBD and THC content. Cannabinoids will be quantified by HPLC to determine regulatory levels of THC, potential yields of CBD, and abundance of minor cannabinoids.