Cannabis Tissue Culture, a Transformative Technology

cannagenome

Over the past decade, the scale and sophistication of the Cannabis Industry in the United States has developed dramatically.  This aggressive transition from isolated small level cultivators to full-scale industrial horticulture has bought about a new set of problems for both government regulators and the cannabis business community.  These problems have become new opportunities for innovative companies looking to push the limits of what is possible with cannabis cultivation.  One of the most significant, changes coming to the cannabis industry is the application and use of Plant Tissue Culture Technologies.

What exactly is Plant Tissue Culture?  The term, is usually defined as the controlled aseptic culturing of whole plants, plant cells, tissues, organs and protoplasts. Aseptic meaning, free from contaminates like insects and other external microorganisms. The procedure for introducing plant cells into culture is relatively simple.

A small section of the plant called the explant, is cleaned and placed in to a sterilized vessel containing a media substrate of agar, sugars and growth regulating chemicals.  In the case of Cannabis, micro nodes are taken from the original stock plant and placed in sterilized test tubes to grow.  After 10-14 days the node has developed into a juvenile cannabis plantlet, with no roots.  Given the proper conditions and fresh growth media, a plantlet can be indefinitely divided into other explants for new cultures.  These new cultures can then be moved into a cannabis depository for storage, placed into bioreactors, used for experimental trials or transferred into rooting media & acclimated for cultivation in the greenhouse environment.   The process of tissue culturing is generally described in four distinct stages.

  • Stage #1 Establishment of Aseptic Culture
  • Stage #2 Multiplication
  • Stage #3 In-vitro Rooting
  • Stage #4 Acclimation

Tissue culture was first used on a larger scale by the orchid industry in the early 1950’s.  The technology proved to be useful for propagating orchids with seed stock that is difficult to germinate.  Today, Plant Tissue Culture technologies are used to preserve endangered species like the Ghost Orchid (Dendrophylax lindenii).  Work done by Dr. Michael Kane & Dr. Hoang Nguyen at the University of Florida[i] is using tissue culture to grow Ghost Orchids in the lab.  Once fully grown the orchids are reintroduced back to their native habitat in the Florida Panther National Wildlife Refuge.

The culturing of plant cells in-vitro is the first step in a number of specialized agri-industrial and biotechnological processes.  Living cultures can be use for micro-propagation, haploid production, somatic embryo-genesis, synthetic seed production callus cell production, protoplast isolation and much more.  The early stages of plant cryopreservation uses tissue cultured cells & special sugars to store the living cells at -190ºC.  Micro-propagation uses tissue-cultured cells grown in bioreactors to produce large numbers of identical plant shoots for starter plants.  Specialized plant cells like anther, callus and polyploidy cells can be produced and isolated using Plant Tissue Culture.   It is simply a matter of time until these types of high-level agri-technologies are applied to the cannabis industry.

Only in the past few years have cultivators and VCs taken cannabis tissue culture seriously.  As real demand increases for cannabis and cannabis related products, cultivators of all sizes will need large quantities of clean, healthy, true to type starter plants.  Intellectual property based around cannabis phenotype development and developed plant traits will rely heavily on tissue culture and cryopreservation as methods of possession of phenotypes.  One of the safest ways for medically significant cannabis phenotypes to be transported and exchanged is as tissue culture in sealed vessels.   Both government regulators and cannabis industry professionals need to be educated about the benefits of this technology so it can continue to develop.

Modern commercial agriculture relies heavily on tissue culture related technologies for commercial production and development. Banana, sugarcane, rice, orchids, corn, soy, ferns and cotton have successfully used tissue culture technologies to make significant crop improvements in recent years. It seems clear that there are considerable opportunities to apply sophisticated tissue culture technologies to the cannabis market.

Micropropagation:

Of all the applications of tissue culture technology, tissue culture based micropropagation presents the greatest opportunity to the commercial cannabis industry. The ability to produce a “True to Type”, pest and disease free starter plants will undoubtedly be crucial to optimization of large-scale cultivation projects. Additionally, all growers, regardless of size, will benefit from the improved plant vigor and crop uniformity commonly seen in starter plants derived from tissue culture. We only need to look to the numerous large-scale micropropagation laboratories around the globe, providing millions of plants for the commercial ornamental and agricultural markets, to see the benefits of tissue culture micropropagation.

During the early years of crop-specific tissue culture micropropagation, the necessary expenses of skilled staff, lab facilities, and electricity, drove the per unit cost significantly higher than more traditional methods of production. This made micropropagation viable only for a limited number of high value crops and endangered plants species. With the introduction of LED lighting and improved quality control software systems, production costs have now become competitive.

As recreational cannabis is adopted in the United States, demand for cannabis starter plants will undoubtedly grow in a dramatic fashion. Between the needs of an increasing number of large-scale cultivars and the growth of straight to consumer starter plant retail sales, fulfillment solutions will be needed. Tissue culture based micropropagation is one of the few methods capable of producing starter plants in quantities to meet this demand.

Crop Improvement:

Tissue culture technologies are often key in large-scale crop improvement programs. Advanced techniques for the culture of protoplasts, anthers, microspores, ovules and embryos have been used to create new genetic variation in plant phenotypes responsible for some of the most significant commercial crop improvements. The implementation of these technologies will power the development of “Elite” cannabis genetics that have specific traits as well as the ability to thrive in a variety of environments. Additional benefits can be realized through the use of single cell and meristem-based tissue culture technology for the eradication of pathogens. The introduction of pathogen-free starter plants, both in the case of food and ornamental crops, has been shown to produce considerable yield improvements for large-scale cultivars. Additionally, the diagnosis and treatment of plant disease can be done while the plants are still in tissue culture thereby reducing the use of anti fungal, and antibacterial chemicals when compared to treatment in a greenhouse or field.

Phenotype Storage:

As the cannabis industry shifts its focus on phenotype-based Intellectual Property rights and branding opportunities, there will be a real need for long and short-term phenotype storage. For entities claiming legal possession of a particular cannabis phenotype, it will be key to maintain the original living plant sample. With the increase of sophisticated cannabis marketing campaigns and the development of commercial trends, access to Elite phenotypes and cannabis genetic information will be necessary for both large-scale cultivation and further trait development. Storage solutions will also be needed for studies that involve the medical benefits of Cannabis since genetically identical phenotypes must be available for study replication and future research.

cryo-meristematic

Current methods for the preservation of original cannabis phenotypes involves maintaining multiple mother plants of a particular strain at different grow locations. This approach is simply not sustainable for large-scale commercial applications. Not only does it carry a high risk of loss of genetic information, the maintenance of multiple mother plant locations is far more expensive as compared to the use of tissue culture.

Many plants have shown an ability to be stored in tissue culture at low temperature for long periods of time without cell damage. Once returned to normal temperature, cultures can be used for plant production without issue. It is for this reason that tissue culture is currently being relied upon for the cryogenic preservation of the world’s endangered plant species as well as the short-term storage of commercial plant phenotype stock.

Cannabis Bioengineering:

Even with the cannabis industry still in its infancy, there are already companies planning on developing transgenic cannabis products. Tissue culture techniques, in combination with highly specialized molecular techniques, have been successfully used to incorporate specific desired traits through gene transfer. Cannabis, like all the high value food and medicinal plants, will continue to be of special interest to the biotech industry. While it will likely be many years, if not decades, before we see transgenic products entering the cannabis consumables market, the potential realization of transgenic cannabis products for the non-consumable & hemp markets is on the horizon.

As the need for tissue culture becomes clear to cannabis cultivators, and more cannabis tissue culture labs open for business, a new high-level sector of the cannabis industry is emerging. New business models based around tissue culture and customized technologies specifically for cannabis cultivation will foster this next stage of development.

Article Credit: New Cannabis Ventures