Breeding micro woolly tomatoes

I grow some varieties of micro tomatoes, the plants themselves reach about 10cm (4 inch) tall.  I also grow another variety of tomato with woolly leaf and black fruit.  So I decided to try and cross them and aim for a micro tomato plant with woolly foliage and blue/black fruit.

For a few years I keep meaning to cross the two, and things keep preventing this or I am not successful in making this cross or all my seedlings die.  Last year I attempted to make this cross again.

One of these seedlings is clearly different than the others

I am not great at cross pollinating tomatoes, my hands are less steady and my eyesight is not as keen as it once was, plus I sometimes emasculate flowers that are a little too old and have already shed some pollen.  

I decided to use Micro Tom as the seed parent.  Any self-pollinated seedlings would be micro dwarf, any F1 plants will be regular sized and have non-woolly foliage.  It should be easy to see within days of the seeds germinating if my cross had worked.

The three seedlings below were collected from Micro Tom.  Two are micro dwarf, and one is clearly larger.  This one is a result of my cross.

Micro Tom x Woolly Blue tomato F1

Once they grew a little larger this cross, between a dwarf and a micro-dwarf, is one of my largest tomato seedlings.  Hybrid vigour means the F1 grows well.

F1 hybrid vigour

The F1 plants will all be large plants, none will be micro dwarf.  I need to save a lot of seed from this F1 plant and grow as many seedlings as I can as the F2 is where I will start to see segregation.

The F2 plants will be a mix of large plants and micro dwarf, each of them will have a mix of regular leaf and woolly leaf, each of them will have a mix of different coloured fruit.  

Given the genes the parent stock had, there is a 1 in 256 chance of getting the plant I want from the F2.

Growing 256 plants does not guarantee what I am after, so I need to plant many hundreds of seeds.  I will be able to cull anything that is not micro dwarf at cotyledon stage.  I should then be able to cull anything that is not woolly at the first true leaf stage.  This will leave me with a more manageable number of plants to grow out to see if there are any high anthocyanin.  

To be honest, I am keen to grow out and stabilise any micro woolly lines even if they are not high anthocyanin as I think that micro woolly tomatoes sound like fun.  There may be some interesting things to come out of this cross.

The seed parent was Micro Tom, the smallest tomato plant in the world.

Micro Tom tomato under 4cm tall

Micro Tom tomatoes

The pollen parent has woolly foliage and high anthocyanin fruit.  It also has a few other interesting genes at play, so there is a lot of potential for interesting woolly foliage micro tomatoes.

Black fruited tomato

I don't have much else to say about these just yet as it is just a seedling.  Hopefully it flowers and fruits in season and I can save seeds.  

Stabilising micro dwarf tomatoes is a bit faster than normal tomatoes because I can usually get 2 or sometimes 3 generations per year out of them, while I can often only get one generation per year of larger tomatoes.