F1 seeds

I'd like to ask a related question: how could I propagate heritage tomatoes? I recently bought some seeds to plant this year. I have read that in order to propagate squashes the pollination is done with a paint brush and the flower petals wrapped with an elastic band to stop insects getting in; would my best bet be something similar with the tomatoes?

Thanks,

Matthew

 

Following on from my earlier question, how do these heritage varieties stay true? How could a new one be created? Am I right to deduce from what is written on this thread that if two varieties were crossed and the subsequent F1s bred over and over amongst themselves, in time the gene pool would be so restricted that throwbacks would be very unlikely and we would be left with a true-breed?

Matthew

 

MatthewJ wrote "Am I right to deduce from what is written on this thread that if two varieties were crossed and the subsequent F1s bred over and over amongst themselves, in time the gene pool would be so restricted that throwbacks would be very unlikely and we would be left with a true-breed?"

I think that's true Matthew. Always assuming that the original F1 seeds will breed. But its not a matter of continual breeding, which would leave the gene pool unchanged. Its selective breeding. Ie you only breed from the plants that show the characteristics that you want. If you do that for long enough you get a pure bred (in-bred) line. Its exactly the same as breeding dogs - you have to be very selective about the parents to get the offspring that you want. And with each generation the line gets purer.

The bit about the paintbrush implies selective breeding, and you keep insects out to stop them producing random crosses.

 

OK, thanks for that. So the heritage tomatoes that I plan to grow this year will be pure-bred (inbred), meaning that if I selectively breed plants of the same variety, the seeds that I save for next year should give me the same thing?

Matthew

 

Think so but as I said above if you grow more than one variety ......will they cross therefore not come true?

 

I assume that there is a risk of that. I think I will pollinate them myself and then try to tie the flowers shut, and hope that I was the first thing to get at the flowers. I wonder how the companies who sell the seeds do it? Do they go to such trouble, or just plant lots of the same variety together and assume that most will be pollinated by the right type of pollen?

 

Good for you Matthew, if you are going to try a bit of selective breeding. I have never done it, but always fancied having a go.

The Plantsman is right - when you grow things in your garden there is always the chance of cross breeding, if you have more than one variety of the same species. I suspect you need a chastity belt for your chosen flowers, both before and after manual pollination. Otherwise you may not be the first to get there. Have a Google on the subject - I am sure that there is loads of information out there.

Commercially, I think they don't bother. I have always understood that the packets of seeds that you buy in ordinary Garden Centres are open pollinated, because its so much cheaper. I asume they are just groups of the same plant grown together in a field, though I am sure they don't put different varieties of the same species next door to one another.

Real specialist growers are another matter. Some will hand pollinate - and you will pay for all that extra work in the price.

 

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hi!

I always save my own French Marigold seeds each year, and am never disappointed, strong plants and better coloured flowers each time!

But these are flowers and if they do not come true, it does not matter.

Vegetables are a different matter altogether, why waste most of a growing season growing dodgy seed and then it is nothing like what it is supposed to be!
F1 seed may be very expensive but normal varieties if bought from Lidls etc are dirt cheap and really do grow well!

Some years some plotholders let maybe carrots, parsnips cabbage or cauli's go to seed, then they are spread all over other plots the next season and they are nothing like their parent plants.
Self sown parsnips in particular grow about 6 feet tall with no root either, I know because I let some grow on the edge of my plot just to see as they were much more vigourous than the ones I had sown in rows!

If anyone wants to experiment fine, that's how we all learn, but don't waste time and effort with something that is likely to dissapoint in the long run.


Cheers

 

I've been looking into this a bit more. It seems that the general method of selective breeding for tomatoes is to use a piece of tulle mesh fabric to make a small bag that covers a young flower. Then to either shake the flower a little to force self-pollination, or remove the fabric for long enough to get a paintbrush in, and then cover again. Apparently the fabric lets in light and air, but not pollinators. So this seems to be the chastity belt from the analogy that PeterS used.

I've also read that tomatoes generally don't cross-pollinate naturally. Apparently not all pollinating insects can reach the stamen, and generally speaking tomatoes self-pollinate (maybe the wind can cause this too?). I suppose this would explain how the companies selling many, many varieties manage to prevent them from crossing. It would also explain how many of these heritage varieties have passed down the generations, in many cases for more than a hundred years, passed on by home gardeners.

 

Thought I'd give it a go this year with saved F1 Beefmaster seeds.The plants were almost identical,strong and healthy the fruits however were distinctly different.The fresh F1's were as always,large juicy and sweet where as the saved seed fruits were smaller ,'dry' and tasted very bitter to the point they were inedible to my palate so I won't be trying it again...

Saved F1 seed on the left...

 

Interesting experiment Loli . I presume a parallel result may happen if I save some F1 flower seeds ? Like Makkas post from 2010 its not worth waiting all season to see the poor result from saved F1 seeds. I never really understood how F1 seed is produced , must have a google later today.

 

Two parent lines are maintained to produce pure characteristics (lets say one is tall, the other is juicy). They are then crossed and the resulting F1 crop is (lets say!!) both Tall and Juicy. Guaranteed every single plant.

If you save seed from that (i.e. "F2") you get some Tall, some Juicy, and some that happen to be both.