Crossing and Bridging with Solanum peruvianum

[William S.]

William, I was reading an article the other day which indicated that S peruvianum can accept pollen from S pennellii. Might be worth exploring as a bridge cross.

Just saw this again and now I have both species in the garden but relatively far apart. Guess I know what I'll be doing on Saturday!

[William S.]

William, I was reading an article the other day which indicated that S peruvianum can accept pollen from S pennellii. Might be worth exploring as a bridge cross.

I think to best exploit this. I should plant a small patch of penellii and one Peruvianum in the center of it.

[Andrew Barney]

I had the chance to sit down and talk with Dr. Bedinger last fall and she indicated that S. peruvianum would be very difficult if not impossible to get crosses with. If it is as hard as she indicated, but perhaps not as impossible as she thinks then I think it could be done with some effort.

[William S.]

Though there is always the exciting possibility that we will get rare crosses, and those rare crosses will be impossible to get any offspring from!

[William S.]

Though honestly there are three avenues that I see right now for crossing in Solanum peruvianum.

1. Solanum arcanum and Solanum chilense bridging lines.

2. Solanum penellii bridge

3. Embryo rescue

I think I would be pursuing the embryo rescue a little more heavily if I didn't have a three year old and had more free time. Might be nice to have a little bit of a set up too in terms of indoor growing. It would be nice to make about 100 pollinations and then do a big tissue culture day. Its not insurmountable, its just larger scale than I am set up for at the moment.

Then there are of course some preexisting strains with some peruvianum in them, A. proving it can be done, and B giving us something to work with for peruvianum traits should we fail otherwise.

My first year working with the Arcanum bridging lines it seems a promising species for us northern growers. I grew it with our peruvianum and entirely expect some hybrids in the second year grow out. If I could get hybrids with the arcanum x domestic, and arcanum x peruvianum I would think the resulting hybrid swarm should allow some transfer of genetics.

For this potential penellii bridge- we already have penellii x domestic thanks to Andrew and penellii x habrochaites x domestic material due to subsequent crossing with the habrochaites crosses. If we got penellii x peruvianum than we have a existing hybrid swarm it could cross into.

Also someone hinted somewhere that pimpinillifolium might cross more readily with it than domestic... Andrew- you sent me a pimp type with exserted stigmas last year.

In my ~2 envelopes of seed from domestic exserted plants I dusted heavily with pollen I did dust with Arcanum as part of the mix. So that rare fertile 0.2 rate seed could be in there somewhere.  I think that I will put one domestic exserted in the Arcanum patch this year and one peruvianum in a purish penellii patch. Also Bumblebees- Wish I could grow out all my seeds- that rare hybrid could be in one of those envelopes

[Nicollas]

From TGC 38 and TGC 33

One way is to limit the peruvianum genepool to LA1708 and LA2172 which can be crossed with tomatoes (but cant act as a bridge to other accessions)

(i've not found how to insert attachments at a specific place in the message ?)

[William S.]

Hmm, I reread the article that led me to the arcanum accessions in the first place and it confirms that. The chilense accession is the really promising one in that article, and not just because it has 0.8 seeds per pollination vs. 0.2 for the arcanum, but because they succeeded in crossing it with peruvianum as well.

Unfortunately the chilense is much harder to grow and I haven't yet attempted it in 2020.

Fortunately the arcanum is interesting in its own right. Just not as a bridge.

That second page you posted. Crossing the F1's seems an interesting possibility which could lead to an arcanum based promiscuous tomato line or an introgression. Interesting.

[Andrew Barney]

I would think logically the ones shown to be closer to each other on this genetic family tree might have better chances at crossing. If that is true then I would expect Chilense to be one of the closer ones to cross to peruvianum. The next closest that we are working with is pennellii or habrochiates.

Maybe we should try with a habrochiates-pennellii hybrid?

I need to look up some of the other species again. I want to say S. neorickii crossed easily with domestic tomatoes. But I can't remember.

[William S.]

I think to best exploit this. I should plant a small patch of penellii and one Peruvianum in the center of it.

In a pot!

[Joseph Lofthouse]

I found an old notebook.

During the 2016 season I pollinated Solanum pennellii with pollen from Solanum corneliomullerii (which i have since merged with S peruvianum). The cross produced about 60 seeds. They were planted, and didn't germinate.

[William S.]

Oooh, aaah. That strongly suggests to me that if we had waited x # days from pollination surface sterilized and extracted the embryos and placed them in sterile media that germination would occur. Same as with Peruvianum as pollen parent and domestic as mother except even fussier  because tinier seed.

Let's hope the reciprocal cross fares better and doesn't require intervention.

[Andrew Barney]

i'm trying to remember, but i think that first year that i did the big pennellii hybrid growout i had only one peruvianum plant that produced fruit abundantly. From what i keep reading, because of self incompatibility this should not happen.

The four wild tomatoes and related nightshades of Chile are, with few exceptions, self-incompatible, and thus allogamous (obligate outcrossers). In the process of growing plants for seed regeneration at UC-Davis, we almost never observe spontaneous fruit set (i.e., without manual cross pollination)

It is possible i had one other plant that could have pollinated it. But i was also growing habrochiates and obviously one of the pennellii hybrids was right next to it. I figure this it is possible that my peruvianum saved seed are hybrids already. actually i now remember i had two peruvianum plants, but they were separated by quite some distance. Still, it makes me wonder why i haven't grown out those seeds yet. Sadly i didn't plant them this year opting instead for Joseph's larger fruited seeds. maybe next year. Either way im heavily invested in this project again. And it is really fun.

p.s. i just requested seed from grin for the peruvianum hybrids. I'm going to try and put one in with TGRC since they have different accessions.

EDIT: p.s. if you look at page one of this thread and table 2 it looks like peruvianum will sometimes cross with chilense and pennellii

[Andrew Barney]

I've requested officially seed from TGRC and GRIN for what are supposed to be Solanum peruvianum hybrids. They will probably have lots of sterility issues and will most likely need a healthy bee population that can cross with compatible S alleles from other wild tomato populations (or by hand). If i get plenty of seed i am planning on splitting it three ways. Some for William and some for Joseph. Hopefully like the pennellii germplasm, we can get peruvianum into this project fully and benefit from those genetics.

I'm thinking of dropping my watermelon breeding and most of my pea breeding next year to devote entirely to wild / domestic tomatoes.

For this year in terms of wilds i think i planted joseph's best wilds and fairy hollow together. I also planted joseph's improved peruvianum, S. galapagense and S. cheesmaniae interplanted, and my suspected pimpinellifolium x habrochiates cross. We will see what grows best and shakes out this year.

I'm leaning towards wanting the various hybrids and populations to be at least somewhat compatible with each other. Basically hoping that the species barriers break down and we achieve something closer to what they were originally long ago before they differentiated into different species. Not sure if that is possible or even fully possible, but i think it would be good for gene flow. In my mind it would be good if the lines became so blurred that it was hard to tell which species was which because they all melted into the same homegeneous but genetically diverse population. But that's just me. i like population genetics and messing with those kinds of things. I'm kinda a mad scientist when it comes to things like that.

The main accessions from TGRC are F5.
Mating System: Autogamous-SC
Sporophytic Chromosome Number: 24
Comments: Resistant to PLRV, TYTV, BCTV, and big bud disease. F5 S. lycopersicum x S. peruvianum derivative.
Categories: Disease resistant; Interspecific hybrid

The ones from GRIN range from no known information other than species cross info to some interesting comments such as these:

Pedigree: L. esculentum (Michigan State Forcing) X L. peruvianum (PI 128657)
Improvement status: Breeding material

Pedigree: L. esculentum x L. peruvianum
Improvement status: Uncertain improvement status
Some degenerate plants occur among BC1 and F2 of L.esculentum X L.minutum due to two or more lethal or semi-lethal genetic factors.

Pedigree: L. esculentum x L. peruvianum
Improvement status: Uncertain improvement status
Some degenerate plants occur among BC1 and F2 of L.esculentum X L.minutum due to two or more lethal or semi-lethal genetic factors. Self, seeds not hairy.

Pedigree: L. esculentum x L. peruvianum
Improvement status: Breeding material
Lines that segregate for the mosaic resistance carried by the male parent.

[Andrew Barney]

Published: October 1972

Breaking breeding barriers in Lycopersicon. 4. Breakdown of unilateral incompatibility between L. peruvianum (L.) Mill. and L. esculentum Mill.

    N. G. Hogenboom

Summary
A brief survey is given of the occurrence of unilateral incompatibility between populations. It is reported how the unilateral incompatibility between L. peruvianum and L. esculentum has been broken step wise by inbreeding with the aid of self-compatibility in L. peruvianum and selection in this self-compatible L. peruvianum material of absence of L. esculentum pollen tube inhibition, and how L. peruvianum material has been developed on which large-scale L. peruvianum x L. esculentum hybrid production is possible. It is concluded that the unilateral incompatibility between L. esculentum and L. peruvianum consists of a complex of separate processes.

[Nicollas]

Had you success with ordering tomato seeds from GRIN ? Unlike species managed by other sections, i've been refused seeds of tomatoes because it is only for breeders, researchers ...