Beginners guide to veg breeding genetics

[Hector1]

I read with great interest the posts here about various genes and your progress in selecting for certain attributes. My knowledge in lower than a snakes
kneecap but interested to learn. Any pointers to simple support?

[Galina]

It depends which vegetable you are interested in for starters. Different vegetables have different genes. Then the next thing is that there are dominant and recessive genes. The dominant being more pronounced in coming through to the following generations. Take human genes for example, brown eyes are dominant. If both parents have brown eyes, their child is unlikely to have blue eyes, because brown is dominant. We have been talking a lot about pea genes, because several people have been playing with crossing peas and creating new varieties. But bean genes are different and tomato or potato genes are different again, which we have not talked about so much.

A book that got me interested and is written relatively simply is 'Breed your own vegetable varieties' by Carol Deppe. I think it helps having the basics explained, following on from what we may or may not remember about Gregor Mendel and his experiments in science class.

[Galina]

If you are interested, there is a pretty big google preview of the book available and if you scroll down you get the chapter on seedsaving and breeding for 8 common vegetable varieties that has a lot of information. https://www.chelseagreen.com/product...ble-varieties/

[Hector1]

Thank you

[jayb]

What crops are you thinking of Hector?

[Hector1]

Choice influenced by space? The most space I have is for Tomatoes or Chillis. Wondering re the critical mass needed for a gene pool? I really fancy playing with taller and dwarf tomatoes or chillis, idea being people without gardens having on window ledges. I shared out Tiny Tim amongst schools and work colleagues and it was grand people getting so excited about growing that don’t usually If I had more room...beans or peas.
Non veg wise, I adore Primula Auricula.

[Galina]

Brad Gates on tomato breeding. https://www.youtube.com/watch?v=Lvz8...N_TaJuQcbNq6lw

[Jang]

Those with far more understanding of genetics than I have will say more I’m sure.
But as far as I understand it , if you’re worried about the gene pool from the point of view of weakening a strain, you don’t need to worry with either tomatoes or chillis as they don’t suffer from inbreeding depression. If it’s from the point of view of the benefit to the human race then it’s a different matter ...... 😏

With tomatoes it’s beautifully easy to keep a variety going as you can rely on them self-fertilising and simply save the seed. So you should be able to keep dwarf varieties going or cross them manually if you’d like to play. Chillis are more promiscuous and if you grow different varieties near each other they will cross unless you take steps to prevent them. You could perhaps grow a few different dwarf varieties one year and leave them to it.

Primula auriculas are lovely. Would you like to breed them?

[Hector1]

Jang, that is very helpful. I had no idea that lack of inbreeding depression with some plants.

Absolutely love Auriculas.

Galina, great link- thank you

[triffid]

Peas and French beans are natural inbreeders - they self-pollinate before the flower opens. If I recall correctly, lettuce is also an inbreeder. So are Cucurbits, but it's a little different as they have both male and female flowers. I'm sure I'm missing others. But there are a good few options for gardeners who don't have fields for massive populations.
Mum loves auriculas, too - the theatres are just so pretty! Admittedly I know absolutely nothing about breeding them, but if I had to guess, I'd wager they aren't suffering from inbreeding either. Just because I suspect there are a lot of hobby growers and auricula fanciers that keep the art alive on a small scale.

[jayb]

Choice influenced by space? The most space I have is for Tomatoes or Chillis. Wondering re the critical mass needed for a gene pool? I really fancy playing with taller and dwarf tomatoes or chillis, idea being people without gardens having on window ledges. I shared out Tiny Tim amongst schools and work colleagues and it was grand people getting so excited about growing that don’t usually If I had more room...beans or peas.
Non veg wise, I adore Primula Auricula.

With tomatoes or chillies you could grow just one F1 plant and then continue to successively grow one plant from the previous plants seeds until stable at say F7. Although this is dependent on each F generation being of a plant and fruit quality that you would want to take forward to the next. So yes if you have space grow more than one plant to select from.

If you made a cross between two similar sized stable dwarf type plants, then the F2's would be similar in size to the parents and you could select one or more to grow out and look for the traits you require, fruit size, colour etc.

But If you make your cross between an indeterminate small dwarf and say a large indeterminate beefsteak with the intention of a windowsill type with small beefsteaks, you would then need to sow enough F2 seeds in order to select plants that have inherited the dwarf gene. The Dwarf gene is recessive and will only be expressed in a 1/4 of the F2 seedlings , it is a good one to select for as it can be seen early on unlike fruit colour. Once you have 'captured' as such your recessive gene ie dwarf growing, its offspring will always be dwarf. You can then make further selections for traits you want.

[Hector1]

This is one of the reasons I love Auriculas. Poster says smells like Lemon Drizzle cake.
https://twitter.com/fluffy_lemonde/s...222703104?s=21