The Seed Ambassadors Project

Bringing Biodiversity Back

Cell Fusion Hybrid Seed is Creepy

Cell fusion CMS is truly anti-evolutionary and is contributing dramatically to the the loss of agricultural biodiversity in the seed industry, as the genes cannot be recovered from cell fusion CMS hybrids.

What is Cell Fusion? What is a Cytoplasmic Male Sterility (CMS) Hybrid?  Why is it Creepy?

Recently I have been asked by several farmers and seed savers to write up a little something about a technology few people know about that is becoming more and more prevalent in our food system. When I bring it up in passing everyone seems to want to know more and their first question is often, “Why have I never heard of this?”  After discussing it with many other organic farmers a question I always get is, “Is that illegal for organic farming?” I answer by saying “No, not yet at least.” And then predictably they say, “Well, it shouldn’t be allowed.”

Cell Fusion CMS Hybrd Seed

Chicory Flower

This technology has been called “cell fusion CMS” and it is used to create male-sterile breeding lines, which are then used to create many common F1 hybrid seed varieties. These hybrid varieties are found in many seed catalogs and including many hybrid cabbage, broccoli and interestingly Belgian endive among other crops.  The technology has been around for the last few decades and is sometimes called hybrid seed from protoplast fusion cytoplasmic male sterility (CMS). I  have nicknamed it “transgeneric cybrid seed.”  It is a kind of a biotech revision of a naturally occurring breeding technique that now straddles the border of genetic engineering. I said revision because some cytoplasmic male sterility can occur naturally – but cell fusion CMS does not occur naturally.

In organic agriculture, GMOs are of course expressly forbidden. I was confused whether this cell fusion CMS technology was GMO or not so I looked up the definition in the IFOAM Standards. IFOAM is the International Federation of Organic Agriculture Movements and they say:

“Genetic engineering is a set of techniques from molecular biology (such as recombinant DNA) by which the genetic material of plants, animals, microorganisms, cells and other biological units are altered in ways or with results that could not be obtained by methods of natural mating and reproduction or natural recombination. Techniques of genetic engineering include, but are not limited to: recombinant DNA, cell fusion, micro and macro injection, encapsulation.”

So by international organic certification standards cell fusion is considered GM, but not necessarily in the United States or in many other countries that disregard the IFOAM standards.  Maybe we all should just start calling it a GMO and have some actual parity in organic standards.  I will now try and explain how it works with as little jargon as possible.

 Let’s create a cytoplasmic hybrid cell… aka a cybrid

My favorite example is based on the the 1996 patent for making chicory hybrids with sunflower mytochondria. Many of the new hybrid Belgian endive (aka witloof chicory) varieties are the result of this type of technique. A cell of a Belgian endive (Cichorium intybus) and a cell of a sunflower (Helianthus annuus) are taken and the cell walls are dissolved away with an enzyme. The chicory cell has its cytoplasm including its mitochondria irradiated and destroyed and the sunflower cell has its nucleus irradiated away. These two broken cells are then fused together into a single cell with electric shock stimulus or a special chemical. What is left is a new plant cell that is transgeneric if not transgenic. The cell is then grown in the laboratory into a plant and is then crossed to another plant to make it more likely to survive outdoors. The chicory nucleus and sunflower mitochondria don’t quite like to be in one cell and create a plant that does not produce pollen and can be used to make hybrid seed. This is evolutionarily dubious and in the wild this situation would be evolutionary suicide.

Without this type of male sterility these seed companies would need to use hand pollination or spray pollen-killing chemicals (male gametocides) or find naturally occurring male sterility or self incompatibility. Many companies prefer cell fusion CMS for various reasons. However, it is probably impossible for a sunflower to cross with a chicory naturally and who knows what the risks of swapping cytoplasm pose to our health, the environment or to the foundation of our food system. The thing that bothers me most about this technology is not whether it is pseudo or actual GMO, but that it further concentrates control over our seed supply in the hands of a few companies whose goal is not to feed us, but to profit off of us.

And yes, seed of varieties produced using this technology are currently allowed on organic farms in the United States and in Europe. Why? Because if we want to eat organic broccoli it must be allowed. (Hear my sarcastic tone?) Honestly, there probably is not enough non-cybrid seed available to sow because most of the big broccoli breeding companies are producing exclusively cell fusion CMS hybrids.

In 2009 there was a meeting organized by The European Consortium for Organic Plant Breeding (ECO-PB) and they discussed what some people call cybrid seed. They produced a very interesting document that I have linked to below for further reading. It is some of the most thought provoking and well considered writing I have read in a long time. It shows that the Europeans have put much more thought into this than us Americans.

The document was titled: “Strategies for a future without cell fusion techniques in varieties applied in Organic Farming”
Some conclusions they reached were:
  • The scientific definition of GMO in Europe and the United States is different than the political definition, meaning Cell Fusion is scientifically a GMO, but is not regulated as a GMO.
  • Lack of labeling of cell fusion CMS hybrids makes it nearly impossible to know which varieties are cell fusion CMS hybrids and which ones are not.
  • Certified organic seed is generally acknowledged to be cell fusion CMS free, but it is not required to be so and may become predominantly cell fusion CMS in the future if nothing is done to prevent this.
  • Cell fusion CMS is truly anti-evolutionary and is contributing dramatically to the the loss of agricultural biodiversity in the seed industry, as the genes cannot be recovered from cell fusion CMS hybrids. To quote plant breeder Jan Velema:

    “Breeding should contribute to a durable and sustainable use of cultivated plants instead of exhausting diversity without leaving anything for our future.”

What Do We Do About It?

If it was up to me no cell fusion CMS seed would be allowed in organic agriculture. However, the more realistic compromise proposal that pops in my head would be to require that only open-pollinated and naturally produced hybrid seed can be certified organic. It is as simple as that. We wouldn’t need to change anything else at least in the short term.

Currently organic farmers can use non-organic seed if an organic substitute is not available. So the big farms that “need” to plant their transgeneric cybrids could continue to do so. Cell fusion CMS hybrid seed should be phased outover time as enough organic seed becomes available. Ideally, organic farms should be strictly sowing organic seed but that is not currently possible, due to current seed supply.  Maybe someday.

If cell fusion is truly classified as a GMO then there will be some interesting fallout. What if the Safe Seed Pledge included cell fusion CMS as well as GMOs? If the Safe Seed Pledge is supposed to guarantee to people that seed companies are not selling GMO’s then should those seed companies continue to sell cell fusion CMS hybrids? Unfortunately if this were to happen immediately then more than half of safe seed pledge signers would probably not be truthful, because so many seed companies are reselling these suspect seeds.

As an organic farmer, I currently buy exclusively open pollinated, non-hybrid seed to avoid cell fusion CMS and I have to be very careful where I get that seed from. If a farmer l

ike me wanted to avoid cell fusion CMS they should be able to buy certified organic seed and be confident that it is not cell fusion CMS. I buy certified Organic food because I can be sure it is not GMO. Seed should be no different.

To quote ECO-PB:
“Protoplast fusion is a breeding technique under the (EC and IFOAM) definition of genetic engineering. Therefore it must not be used in organic plant breeding and seed originated from it should not be allowed in organic farming.”


  1. I found this information valuable.

    Thank you,


  2. Am I clear that these plants could not contaminate other plants because they cannot produce pollen unlike GMOs that could ruin an organic by cross pollenating? One could avoid these by only buying OP seeds. But there’s no way to know what you are getting in the market since these are currently allowed in organic agriculture. The organic broccoli we’ve been eating may well be grown from cybrid as well as regular hybrids. This is scary. I will continue to buy organic to avoid pesticides. I am thankful to have seed growers like you who will not be selling these kinds of seeds.

    • Thanks for the comment Jodi, You are right that the cybrid seed is not a contamination risk. One of our questions to to the big seed engineers is, why do they not keep their GMO traits in the male sterile parents? This would limit the GMO contamination problem, but they don’t seem to care enough about it.

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