I’ve begun harvesting the ripe fruits from the Solanum habrochaites crosses. What I find very interesting is the overwhelming dominance of the habro genes: leaf form, overall plant habit, flower size, strongly exserted stigma and small yellowish green fruit. The only things obviously missing are the vague stripes and the downy hairs on the pure habro fruit. There is no other apparent representation of the tomato mother! I used four different tomatoes as mothers: College Challenger (medium sized red), Jaune Flammée (saladette sized orange), Matts Folly (red grape type cherry with gold stripes) and Pink Berkeley Tie-dye (pink beefsteak with multi-coloured stripes). The two in the picture are from the first two but all the F1 fruit look the same, regardless of tomato mother. The plants these came from were all grown together next to two tomatoes, Loxton Lass, an orange beefsteak and a small red-fruited tasty little tomato said to also have S. habrochaites in its background. Because the hybrid had such strongly exserted stigmas I’m hopeful that they will have crossed a) with each other and b) with the tomato neighbours.
Note that in the pic the label says F2. This label goes with the seeds inside the fruit.
This seems like a very familiar happening with early generation 50% Solanum habrochaites crosses- even 25% Solanum habrochaites. I’ve been very curious what the effect of using fancier tomatoes as first crosses and you may have just shown that in the early generations it may not mean much! Though I still think it could make a lot of difference down the road in terms of getting to fancier tomatoes faster because you only have to fight the habrochaites not the boring red domestic it was initially crossed with. I also wonder if certain traits I’ve seen in habrochaites could lead to neat new visible traits in their eventually palatable descendants. It is a long slog though breeding with habrochaites!
That’s disappointing. Sounds like it may be a good idea to make some backcrosses into tomatoes I like in order to speed things up a bit. In any case, I’ll keep growing the habro descendants in among tomatoes I like, selecting those habro descendants each generation with exserted stigmas to save seeds from. Even without a deliberate backcross, the population should move in the desired direction by growing and selecting this way, albeit slowly.
The results of my deliberate back cross to domestic last year are now growing, though with some minor difficulty, which I assume is fairly random overwatering damage. Have about two really nice-looking seedlings with true leaves and another few that aren’t as healthy. Have vastly more F2 plants and more F2 seed if needed. My F2 are technically 5/8 wild as I used an elite from Joseph’s promiscuous project. The back cross is technically 5/16th’s wild. I have some new crosses which are 1/2 wild but the deliberate F1’s have had a fairly low germination rate. I say it is a long slog largely because of my experience with Joseph’s original project. I have been growing it consistently in various iterations since 2018. The back cross Joseph made led to the elite generations, but not without a large population size. My new project is only two years into crosses though I have been growing the arthropod resistant Solanum habrochaites parent for three as I didn’t manage crosses the first year. This is the fourth year and I am growing the pure habrochaites, new F1’s with Big Hill, Mission Mountain Morning, and Promiscuous, the domestic backcross with Mission Mountain Morning, and the F2’s with Promiscuous. It is theoretically possible some habrochaites back crosses could be in the population as I have not been isolating and habrochaites is the best pollen producer in the population. The F2 is definitely segregating for small wild type seedlings and large domestic type.
I’m overwintering three habro plants and by sheer coincidence one tomato x habro F1 (Pink Berkeley Tie-dye). Last summer I tried using some pollen from one of the tomato x habro F1s on a habro flower but it didn’t take. Since I happen to have an F1 overwintering I thought I might as well try again. I now have two swelling fruits on one of the habro plants. Fingers crossed that they have viable seed. I’m now encouraged to do a few more using the other two habro plants as seed parents. I’ll be very happy should I have some seeds that are 3/4 habro 1/4 tomato with habro cytoplasm come spring.
Since I have the F1 I decided to grow a few tomatoes to cross with it so that come spring I will have some seeds which are 3/4 tomato 1/4 habro with tomato cytoplasm. The varieties I’m trying to grow are Cherokee Purple, Jade Beauty, Japanese Black Trifele and Wherekowhai. Three of them are potato leaf chosen deliberately to make successful crosses obvious early in the season.
Keeps me going over winter 
And:
The question that arises in my mind as being important is, if he crossed domestic X hab. to hab. as mother, was that resultant cross able to cross with domestic as father? (Or to one of Joseph’s wildings etc.) Presumably that’s the aim, right? So that we have a hab. female line in predominantly domestic tomatoes, right?
I think Joseph has this to the point where the hab cytoplasm line has colored fruit. Can’t remember if he said it tastes good yet.
Yes, that is my aim. I don’t know whether a habro line that is 1/4 tomato will accept tomato pollen. Next season, with any luck, I will have tomato lines that are 1/2 habro and 3/4 habro. I will be using these, as well as tomato, to cross back into the habro line(s). I should eventually get what I’m after.
I regret not making any deliberate 3/4 habrochaites crosses last year. There may be some natural ones but if so they are either still seeds or I haven’t distinquished them from the 1/2 habrochaites. I may make a point to make the cross this year. I may try it with both species as mothers and see if they both take.
Over the southern hemisphere winter I crossed a tomato/habrochaites hybrid with a full habro mother:
Solanum habrochaites x
(S. lycopersicum cv. Pink Berkeley Tie-dye x S. habrochaites)
I sowed the seeds of this cross last week and amazingly I have several tiny seedlings. If they survive I’ll have plants that are 3/4 S. habrochaites and 1/4 S. lycopersicum with S. habrochaites cytoplasm. So hopefully I’ll be able to build a landrace with diversity in cytoplasmic genetic material as well as nuclear.
I also hope to make some crosses with S. pennelli. I’m growing some S. cheesmaniae too. I don’t think they’re all that far removed from the domestic tomato so using it in a cross isn’t a priority.
Cool. I pollinated some of my (mostly) lyc x arcanum with arc. pollen and now have a 75% arc. growing, and some more seeds germinated. And I have some arc x (mostly) lyc x arcanum fruits growing. I figure with the latter, I can use them for:
- Crossing to lyc or some other lyc x wild hybrids, to make 37.5% arc plants
- Increase the SI alleles in the general arc cross population using both of the above
- Try getting the female line by first using pollen from 25% arc flowers, to being them down to 50%, and if that doesn’t work, try the 50% arc pollen, to get 62.5% and then next cycles bring them down to 31.25%, or less if using lesser percentage pollen, if less proves useful.
Yeah that’s straightforward enough. I made some hab x che and hab x gal crosses, seems pretty easy by the look of the seeds though haven’t germinated them yet. Same using pen instead of hab.
My Solanum habrochaites LA2329 crossing project just died down a couple weeks ago from frost for the winter. I didn’t get back any pure LA2329 seed this time and I still didn’t make any 75% crosses for sure. I may have gotten some pure LA2329 or bee made 75% crosses mixed into the seed I saved though as the 50% crosses are very wild looking. I grew both promiscuous x LA2329 F2 and promiscuous x LA2329 F1 and I couldn’t tell much difference except for some minor size segregation.
I only got back seed from one 1/4 LA2329 plant. I doubt it will be ideal, but it was yellow in the F1 so it should segregate interestingly next year.
I made some new 50% crosses. Notably with Exserted Tiger and Exserted Orange. I also made new 1/8 crosses and new 1/4 crosses. I think one new 1/4 cross was with a 1/4 galapagense.
I have been trying to somewhat preserve the exserted nature of my LA2329 project by choosing good domestic parents.
This season’s tomato crossing patch.
Rows L to R
Tomatoes to provide or receive pollen
Tom x habro F2 to provide or receive pollen
Habro x (tom x habro) to receive pollen
Same as row 1
Same as row 1 (not shown in pic)
In this bed I have also sown sorghum, corn, buckwheat, flax, cowpeas, beans, chia and melons. The corn and sorghum will provide a bit of shade as the summer advances.
The pallet fence provides some protection from our nasty westerly winds - hot and dry in summer and very cold in winter.