Woolly micro tomato update

It is time for an update on my micro woolly tomato breeding project.  

For a bit of background, I crossed a micro tomato which only grows to about 10cm tall, with a woolly leaf tomato which reaches about 6 feet tall.  I used a micro tomato as the seed parent so it was simple to see if the cross worked really early. 

I grew the F1 in the year 2021, the F1 plant reached about 5 feet tall, was very productive, and the fruit looked intermediate between both parents.  

Micro woolly tomato breeding

I culled the F2, only keeping the smaller woolly leaf plants.  Then culled subsequent generations based largely on plant size, and to a lesser extent based on fruit colour and taste.  Last year I had a mishap and lost many of my seeds from this project, sadly things like that sometimes happen in breeding projects. 

This summer (2023-2024) I culled and was left with four candidates, I put the four candidates in one pot for ease of handling.  

While it is far better to have them in separate pots, or even in the soil, that was not an option this year.  

Woolly foliage tomatoes

The four remaining plants are between 5cm tall and 15cm tall, they all set flowers at their terminal bud, all are woolly, and all appear to be expressing anthocyanin in their leaves and stems.  

At this stage I don't know what base colour the fruit will be, or how they will taste. 

Unripe woolly tomato 

While several of the plants are larger than Micro Tom (pictured below), up to 15cm tall, or about 6 inches, is still probably considered to be a micro dwarf tomato.  These were partly shaded in the greenhouse and are likely taller than they would have been if grown under direct light.  There are a few generations until they will be stabilised, so even if they are not micro dwarf tomatoes that is ok at this stage.  

The smallest candidate is producing flower buds, and is only around 5cm, or about 2 inches, tall.  This may be a genetically tiny plant, or it may be stunted by growing so close to the pother plants.  I won't know until I grow out its seeds.  

Micro tomato plants are tiny

One of the things I like about micro tomatoes is they are so quick to mature that they can produce several generations each year.  My winters can be a bit long, so I sometimes lose a generation to frosts, but in a mild year I can grow a few generations and make some decent progress.

I was growing these plants in my greenhouse as I didn't start them until late in the season and they needed protection from the heat.  I have recently moved the pot outside into full sun.  Hopefully there is enough heat left in the season for them to set fruit and for me to collect seed.  

Woolly foliage, high anthocyanin 

Even if all goes well, this project is still a few generations away from completion.  Hopefully one or several of these four are what I am hoping for, then I can work on stabilising the lines.  

Fingers crossed in another few years I have a few stable lines of new micro tomatoes that taste good.  If not, I can do a little back crossing to lock in the traits I want, or I could start again.