Triploid Breeding: An Interview with Benjamin Lind, Co-founder & Chief Science Officer, Humboldt Seed Company

Since cannabis has become a state-legal commodity in much of America, cannabis breeding has developed into much more of a science. I recently had the opportunity to have Benjamin Lind, the Co-founder & Chief Science Officer for the Humboldt Seed Company, answer my questions about triploid cannabis.

Vivian McPeak: How widely is the triploid approach used in cannabis today, and how long has the triploid method been employed in cannabis breeding?

Benjamin Lind: We are at the tip of the spear in terms of the utilization of triploids in cannabis. Triploids started to be employed in the hemp industry a couple of years ago. This was the first step toward breeding triploids specifically for seed. We are just now seeing the triploid approach making its way into THC cannabis breeding. We became interested in investigating the possibilities further after discovering a naturally occurring triploid during one of our pheno hunts years ago. Not many people are doing it. A handful of legacy breeders are exploring the possibilities.

VM: What is the difference between diploids, triploids, and tetraploids in plant breeding?

BL: The number of chromosome pairs is what differentiates a diploid from a triploid, from a tetraploid. It takes a diploid and a tetraploid to make a triploid. This is a case of 2 plus 4 equals 3. The tetraploid is created from a diploid where there is interference during miosis. This can occur naturally, but is very rare and is accomplished in targeted breeding by using a natural chemical derived from the Autumn Crocus bulb (Colchicum autumnale). The miotic process is interrupted during the phase when the cell is supposed to split and you end up going from 2 to 4 pairs of chromosomes in the same cell.

If you already have a diploid you can make more diploids, or if you have a tetraploid you can make more tetraploids. Foundationally, it’s the same plant breeding procedure.

VM: How does cannabis produced by the triploid approach differ from the conventional breeding practices that most consumers are familiar with?

BL: Triploids grow faster and flower faster. They are vigorous and stretch more than non-triploid plants. As far as aesthetics go, the buds are gorgeous. Super frosty, large and dense. And the aromas are as good or better than their diploid counterparts. They are easy to grow and since they are around for less time there is less of a chance of things going wrong.

The smoking experience is not that different from other choice, high-quality flower, although we have seen a 3-5% increase in THC in the triploids we have bred. Triploids offer more of an agronomical advantage than a huge difference in the consumption experience. The increase in production is particularly valuable for extractors, potentially yielding a 10-15% increase in fresh frozen live rosin.

VM: Does the home or craft grower do anything different when growing cannabis from triploid seeds?

BL: When growing triploids, switch to flower cycle earlier than normal. You want to start flowering fertilizer a little earlier and make sure to account for the higher phosphorus intake. Another big consideration is space. They will stretch much faster and grow much taller, so you have to be ready for that.

VM: Do triploid-grown plants have any added pest-resistance properties?

BL: There is promising evidence that triploids have enhanced pest resistance. In our large-scale field trials we saw plants that appeared to withstand pest pressure better than non-triploid plants. There are phenotypes of other plants such as oranges where triploids are more disease resistant and we can guess that it might be the same for cannabis. To what extent durable pest resistance is present in all cannabis triploids will take time to figure out. We are excited to gather more data as we complete more field trials this year and hope to have a clearer picture of the pest resistance of triploids soon.

Triploid vs. Diploid wash test with Rosin Dial showing 10% increase in yield: