What is micropropagation?
Micropropagation is the set of methods used to rapidly propagate plants in sterile containers, typically in a lab setting. The term "tissue culture" is often used to reference micropropagation, however, they are not the same. Tissue Culture refers to the growth of a single tissue type, such as animal liver cells or red blood cells. In the case of the propagation of plants, the goal is to produce complete plants comprised of their various tissue types, not a single type.
How micropropagation differs from other methods of propagation:
Ultimately the principles in play in micropropagation are the same as those utilized by traditional methods. Certain portions of plants are able to regenerate into complete copies of the original plant. These portions are often referred to as "explants". Explants can be taken from mature, non-sterile plants, such as those currently growing in a greenhouse. They are then sterilized, and propagated via micropropagation. This approach results in a single clone. Nepenthes tissue is notoriously difficult to sterilize. As a result, we do not currently utilize this method.
Another approach is to utilize seeds. Seeds are often much easier to sterilize than unclean tissue taken from a mature plant, and can produce extensive genetic diversity. Imagine 100 seeds germinated in sterile culture. Each one then becomes a unique numbered clone of that species or hybrid. These individuals can then be cloned indefinitely, preserving genetic diversity. In sets of plants containing hundreds of different clones, a customer can purchase several plants and have a very low likelihood of receiving two plants of the same clone. Though they are not truly genetically unique individuals, the genetic diversity within a set like this rivals that of a batch of seed-grown plants.
Nepenthes often take 5 or more years to reach flowering size and then flower at unpredictable intervals. Pure species seed is therefore incredibly difficult to produce once, much less regularly in order to supply continuing demand for the item.
A while back we created a survey which asked various questions. One of the questions asked if our customers preferred species or hybrids. Species was the winner. Another question asked if our customers preferred more expensive "high-end" items, or less costly plants. Lower cost won out. In summary, we found our customers preferred pure species, but wanted them at a lower cost. Micropropagation offers the clearest route to that goal. Cuttings take years to produce and only result in a few clones of the original plant. Propagation of pure species via traditionally sown seed can take decades due to the time it takes for Nepenthes to grow to flowering size, and then take years more for the seeds to be grown out to a sellable size.
How it protects wild populations:
Micropropagation protects wild populations by producing large quantities of plants rapidly, therefore eliminating the market for wild-collected plants, which are often much more expensive, and rarely live long-term due to the stressed of being collected from the wild and then being shipped internationally. Traditional methods (cuttings or seeds sown traditionally) are far too slow to meet demand within a reasonable amount of time. From the time a new species is discovered, through micropropagation, sellable plants can be ready within 1-2 years in large quantities that are rapidly replaced once sold. Eliminating the financial incentive for poaching is the best means we have to disincentivize the taking of wild plants.
The role micropropagation plays in the future of PRE:
Over the past several years we have been amassing quite a large collection of plants for breeding. In the past year we've had more than 10 plants flower and have created many new hybrids as well as pure species seeds. The vast majority of these are sown in sterile culture, allowing us to create a sustainable source of genetically diverse clones. In most cases we are keeping the clones separately numbered, sometimes over 100 different numbered clones of the same item! Our breeding program and micropropagation lab are therefore closely intertwined. Our goal is to increasingly self-supply our inventory and we are working hard to make that happen!