CST Blog: Dwarf Tomato with Craig LeHoullier

Craig LeHoullier aka ‘North Carolina Tomato Man’ is the plant breeder behind the F3 teensy family dwarf tomato breeding population that we are trialling in the 2020 Citizen Seed Trial (CST). Craig is also the co-founder of the Dwarf Tomato Project and is responsible for 90 (and counting) tomato varieties, including Cherokee Purple.

We are excited for Craig to be sharing his plant breeding knowledge with us on Thursday June 18th from 12-1pm PST, 2020, for the Dwarf Tomato Breeding Webinar. The background of the Dwarf Tomato Project and will gain some insights into the breeding population seed that was provided for this year’s trial.

[The link to the webinar recording can now be found here]

Before delving into the webinar, here is some introductory information about the 2020 CST tomato breeding population;

Species: Solanum pimpinellifolium

Generation: Dehybridized F3

Family: Teensy

Breeder: Craig LeHoullier, Dwarf Tomato Project

The initial cross occurred between a Mexico Midget (P1) X Summertime Green (P2) by using the pollen from P1 and hand pollinating a deanthered flower of P2.

– Mexico Midget is an indeterminate pimp tiny cherry tomato and Summertime Green is a dwarfing plant with 1-pound green fruit.
– F1, the progeny of this cross yielded red round cherry tomatoes that were far larger than Mexico Midget and far smaller than Summertime Green (as expected).
– F2, when grown out, segregated in an expected manner into 75% indeterminate (none of which have been explored, since the project goals centre on plants with a dwarf habit), and 25% dwarf – initial selections for colour were clear skin and dark crimson flesh – like Cherokee Purple.
– F3, seeds were only saved from the dwarfing plants, when grown out we will expect to see 100% dwarfing plants which should now be stabilized but colour, size, shape and flavour will be highly varied.

Overall the teensy family has shown to be very prolific and have good flavour!!

For the purposes of the Citizen Seed Trial (a variety trial) we are critically observing the traits of this breeding population and are comparing it to the Soleil Orange Cherry Tomato. We are looking for traits that are desirable, in the case of the dwarf tomato project – Craig is selecting for dwarf plants with tiny and flavourful red fruit. Since, colour, size, shape and flavour are not stabilized yet for this breeding line, people could make different selections that suite their own needs. In addition we are observing and evaluating performance in germination, disease resistance, earliness, vigour, storage, yield and flavour! Participants are welcomed and encourage to save seed from this variety – please consider the population size, isolation distance, flowering times and life cycle in your seed saving plan. More information on tomato seed saving can be found here and here for a more comprehensive overview of breeding tomatoes for organic agriculture.