Breeding with wild tomato species

[Andrew Barney]

https://phys.org/news/2020-09-analysis-wild-tomatoes-elucidates-genetic.html

This article was interesting today.

[Diane Whitehead]

plus the next article with a link at the bottom, and the next linked article at the bottom of that one.

The third one was on suggestions to promote parthenocarpy.

[Andrew Barney]

https://keen101.files.wordpress.com/2020/10/wide_hybridization_in_vegetable_breeding.pdf

[Diane Whitehead]

  Which project are you going to copy?  It seems the only ones that have gone on to successful use are the wide crosses of brassica.

I wonder if any of those tomato experiments were carried on so that seeds might be available now.

Will you be a good parent and guide the hybrids' characters by clever training?  I wonder what they really mean by that - perhaps it is a poor choice of terms by the translator.

[Garrett Schantz]

Some odd things happening with a single pimp x habro F1 plant. This is from a plant I collected outside from before. First image the top part of the leaf is in a heart shape. Second image seems like the top part fused with another leaf. Third image a leaf is coming from opposite from the others, couldn't get a good up close of it. Fourth image is the stem. White streak on it, two stems are shooting up and are somewhat fused. Can't recall snapping it or anything that would cause a 2nd shoot. I posted more images of seedlings on a Twitter that I created - this way I am not posting too many images here. It saves me the trouble of trying to find a image host - my images will be watermarked or eventually expire with one of those. Rather not take up all of the space here. @GarrettSchantz_ is the tag if anyone wants to look.
 Andrew - the article you posted is interesting. Hopefully the full study ends up somewhere eventually.

[Garrett Schantz]

Some fun updates, plants are starting to grow a lot faster, noticing more traits. The pimpinellifolium had a ton of suckers. Seems like the hybrid has this trait as well. The larger crosses are getting suckers on EACH branch. Some of them that have lost their cotyledons have suckers appearing in those areas as well. So the plants will probably be large, bushy and have multiple suckers. Some of the crosses got "leggy" due to poor lighting. Used a parent as a test and then moved on and further tested the crosses. I will probably allow some suckers to grow on some plants and then allow it to bush out towards the middle, topping it off afterwards. First image is the largest plant I have currently. Third image is the pimpinellifolium that I cut far down, only leaving about two leaves which I also removed after the suckers grew large enough. Fourth is the base of one of the plant's stem. Really deep purple, felt around at the base and the color there is just due to it becoming sort of "woody". With that I will also point out that these plants are really stiff/sturdy - both parents were somewhat stiff. They aren't fragile but still not a trait I really want. Some of the hybrids that were glossy earlier on are now becoming slightly fuzzy. Also haven't fertilized any of the hybrids yet. Happy with the growth on them. Being potted plants grown for F2 seed, I will need to fertilize them eventually. These will probably have large trusses.
 Fifth image is of 3 different chilense accessions that I acquired. Only planted around 2 seeds from each type, just to make sure germination was fine. Started a few peruvianum types for this purpose as well. One of the chilense had black seeds and regular looking seeds in the packet - they were larger than the other two other types I got from another source. Its the smallest in the image with no true leaves on it so far. Middle chilense is supposed to be a larger growing type. The chilense on the top is a smaller growing variant. Cotyledons are different on the small / large accessions. If they grow fine, I will probably attempt crosses between them. They are growing a bit close together but I would rather not upset the roots, this was a test anyway so if they don't grow too well it is fine with me. Probably going to treat it similar to a xerophyte type of plant / like a cactus. Unsure of how well the taproot will enjoy the pot I have them in.

[Andrew Barney]

Fourth is the base of one of the plant's stem. Really deep purple, felt around at the base and the color there is just due to it becoming sort of "woody". With that I will also point out that these plants are really stiff/sturdy - both parents were somewhat stiff. They aren't fragile but still not a trait I really want.

Yeah the wild ones are very woody. I think that may be why they do not root easily like domestic tomatoes.

 I've found that scarring joint nodes and letting them heal with scar tissue will create a spot where they can root if cut off the parent plant later. Otherwise cuttings never root and they will die.

[Garrett Schantz]

I might try scarring the joint nodes so that I can have F1 cuttings, thanks for the idea. Wild pimpinellifolium crossed with a habrochaites... At least the F2 will be grown outside and probably have red fruit and other fun traits. Assuming I will end getting some with green fruits that are pea sized. The plants I am growing now will probably have fruits identical to habrochaites due to being F1s. Seems like habrochaites has dominant leaf size and type. Both parents are still alive and flowering, so there is cold / light frost tolerance. Normally would have had at least one heavy frost by now. The pimpinellifolium is looking pretty bad though, cold weather slowed it down but the blight kept coming. Habrochaites was damaged by a light frost in September, leaves curled inwards and became sort of black. They recovered quickly. Believe I posted some images of the pimpinellifolium on here before. Leaf color reminded me of coastal types of plants like oyster leaf or sea kale - the color seemed to go away in the summer on newer leaves but I noticed it again in the fall. Branches started drooping as soon as I put them outside - assuming grow lights forced them to grow upwards to some extent. Leaves were pretty small as well. Branches folded inwards during the nights, noticed it the most on newer growth. Assuming this originated near a beach/coast or something but I have no info on it. Found some old photos for reference. The reason I'm getting so much F1 variation is probably because I screened out over 40ish fruits for odd leaves, which isn't very hard since the parent had almost no serration. I was using the parent on the habrochaites plants as a sort of trellis - they started doing it by themselves and I helped it along, the flowers were all close together afterwards which probably made cross pollination greater. So I probably got multiple crosses over and over again which gave me some very slight variations - mostly in leaf size. The photo showing the blue-ish leaves has habrochaites fruit and leaves in the background so that can be used to scale the leaves/plant as well. Smallest pimpinellifolium plant I have grown, seeds were smaller than Galapagos tomatoes I have grown as well. Sort of habrochaites sized. Solanum pimpinellifolium seems to be pretty wide-spread so there is a good bit of variation within the species which is nice.

[Joseph Lofthouse]

My experience is that F1 hybrids between red fruited domestic tomatoes and green fruited Solanum habrochaites produces light yellow fruits. I'd expect the F2 generation to segregate for red, green, yellow, pink, white, orange.

Are you using a self-incompatible Solanum habrochaites? If yes, I suspect that the variation among the F1 is because solanum habrochaites is heterogeneous because it's an obligatory out-crosser. 

[Garrett Schantz]

I bought a few Solanum habrochaites from different seed sources. Put around two of each habrochaitrs around the pimpinellifolium which was slightly exerted. Most of the habrochaites branched outwards, but one of them was bushy. The flowers dropped on the habrochaites when I first planted them, started fruiting when bees visited them. Assuming they were self-incompatible. Saved seed and screened them out for anything off type.The pimpinellifolium was pea sized and had red fruit. Couldn't really find any use for the fruit due to the size, so ended up getting a lot of seed to screen out. Will probably get light yellow fruits based on what you said.

[William S.]

Just a mini update on G6 and G7 of the promiscuous project which are also G3-G4 since backcrossing to Big Hill. So 75% domestic.

I definitely pulled a lot of bicolor plants out of thsee generations. Pictured is perhaps the best of these particularly size wise. Not so big as the XL line but bicolor for sure.

I suspect that 90% of these generations or better were displaying delayed fruit set. One plant in particular I thought maybe was a selfer. So my take is that most of them do have obligate outcrossing. Though I didn't do the rigorous evaluation of them for that that Joseph and the Idaho crew did this year.

However there may be evidence for selfing beyond that because some of the XL line are just too good to be true otherwise.

I think some of the penellii descended plants just didn't produce again.

Hmm.

One line of inquiry is the habrochaites cytoplasm lines and if its true that they should only accept pollen from obligate outcrossing plants... I think I'll be surrounding a few of those with these pretty bicolors next year.

Another thought is that less is more for started plants. Having them spaced far enough to evaluate on a plant by plant basis and maybe do some hefty culling would be great.

Though I definitely have enough seed now for a row or more of direct seeding too.

[William S.]

One interesting thing was that last year I grew 13 plants of W4 x BH. All 13 were wild type and I saved all the seed. This year I planted an awful lot of it. Some as transplants and some direct seeded. There were a few plants with minimal improvement but mostly it was all still wild type habrochaites. So given the vast success of the seed from the elites Joseph selected, I just kind of enjoyed the plants and didn't bother to collect any seed from them. Notably they did work direct seeded. I have a couple seed packets from nearby exserteds that could be contaminated by it. Though that's been true ~the last three years or so. It did work notably well direct seeded. I wouldn't be surprised to encounter some volunteers next year.

[Garrett Schantz]

Didn't get snow last night but today the habrochaites and peruvianum were pretty much wiped out - weather got into the 30F range last night and the ground was a bit moist from rain a day or so prior. Habrochaites newer growth survived - on all plants towards the bottom of the plant, didn't see anything new on the peruvianum. Assuming the upper leaves shielded the newer growth. Some nice long roots on one of the habrochaites which also happened to be the one with larger stems, grew more like a shrub than the other types I tried out this year. Managed to get some unripe fruit that started coming on during the start of fall. Hoping any viable seed will be better acclimated to the fall weather next year. Flowers were larger in the fall, and more flowers overall as well. Same with the peruvianum. Daylight sensitivity I suppose. Have a bunch of pimpinellifolium and habrochaites seed that I fermented mixed together. Going to use them as direct sowing tests next year. Could be more crosses in there as well I suppose. Crosses getting more leaves per stem than domestics/pimpinellifolium, fuzzy leaves etc - newest growth is looking like two different sets. Meaning I might get flowering branches soon as well. Some of them are looking more like my bush type, unsure of how well they will grow in pots.