Dehybridizing Carrots?

[Walk]

I just got a couple of boxes of beautiful carrots from a local farmer friend. They are Bolero (Heavy Nantes), a F1 hybrid from Johnny's, with more bulk than Scarlet Nantes and great for storage. I was wondering what I would get if I grew some of them out next spring for seed? Are carrots easy or difficult to stabilize as an O.P. from a hybrid?

[keen101 (Biolumo / Andrew B.)]

Well i'm not an expert and i'm sure others will chime in shortly on the subject, but here is what i know about it.

There have been a few threads about this subject in the past, the most notable one (or two) mention that something like 60-90% of commercial hybrid carrot seeds use a technique called Cytoplasmic Male Sterility genetics (CMS). For home gardeners and home plant breeders this presents a major problem as the seeds from these will produce plants that do not produce pollen and will need pollen from another carrot source to produce viable seeds. And even if you were able to do so, that means that CMS might remain in your overall population for several generations.

Now not all F1 hybrid carrots are CMS, but i would venture a guess and assume they are.

Joseph and others posted a neat thread on the subject on how to look at the flowers and tell and therefore you can periodically pull those out of your carrot population. I can try and see if i can use the search feature to find one of those threads. I know there are several people here that are activley breeding carrots and a much further along than i am so they know a lot more. But i think many of them would say to start with open pollinated carrots to begin with. Some of the carrots i like come from baker creek seeds, but i'm also on the lookout for carrots that do well in clay soil, so i think i may need to start looking into short stubby carrots. I think Templeton or one of the fellows from Australia are working on a neat short stubby colored carrot breeding project that looks neat.

Here are the ones i could find:

alanbishop.proboards.com/post/75887/thread

alanbishop.proboards.com/thread/5698?page=2#61235

[billw]

CMS will remain in your population forever, unless you eliminate all of the plants that have it. Therefore, if you don't want CMS, you should start by not choosing a male sterile variety for dehybridization. Unfortunately, most hybrid carrots are CMS. Maybe somebody here has already looked at Bolero. If not, I would plant a few of those carrots and check for the presence of normal anthers next year. If they have them, great. If not, then you are looking at a long and indirect path to stabilization.

[Joseph Lofthouse]

Bolero cannot be stabilized. Because it does not produce pollen. Therefore, it requires a pollen donor to make seed. So each generation, the pollen donor would be diluting the Bolero genes. By half the first generation. By 75% the second generation, etc... If the only pollen available is pollen from Queen Anne's Lace, then the carrot will revert to a wild state in the first generation.

In my own garden, I chose to only grow carrot varieties with healthy flowers that produce both seeds and pollen.

However, it would be perfectly possible for a home-scale gardener to produce stabilized hybrid carrot seed. The process would go about like this.

• Maintain two separate and stabilized open pollinated carrot varieties.
• Take a male-sterile carrot variety, and pollinate it with one of the open pollinated carrots for enough generations (5) that the original genetics are highly diluted.
• 
  Then, make the hybrid by pollinating the male-sterile variety with the other open pollinated variety.

[Walk]

Thanks everyone for your replies. It sounds like my best option is to eat these gifted carrots and stick to growing my O.P. standbys. Maybe the reason these carrots look so nice is that they're grown on deep loamy sand rather than our garden's clay. We usually have better luck with the Chantenay types here.

[ilex]

Yes, assume cms on hybrids. That's a dead end unless you are able to take the cell nucleus and put it in another cell.

There are plenty varieties and diversity to choose from, or select your own, without needing hybrids. You could have some hybrids in a landrace but you risk ending with too few pollen donors and ruining it. I would not do it.