My wild tomato breeding project
 

As luck has it now I have seed on the way for

Lycopersicon glandulosum

Lycopersicon cheesmanii

and seed for two crosses

Lycopersicon esculentum x peruvianum

Lycopersicon hirsutum x esculentum

So should be able to make some interesting crosses next year.

I will be using the wild types as the male in all crosses.

Let me know of any crosses you might think are interesting here is a list of the seeds i have that I might could cross with the above types

Minnie's Pinstripe
Bonny Best
Purple Hillbilly
Cherokee Purple
Amish Potato Leaf
Depp's Pink Firefly
Sparks Yellow
Cowlick's Brandywine
Chocolate Stripes
Fred Limbaugh Potato Top
Cuostralee
Brandywine, Sudduth's Strain
Black Cherry
Current
Early Glee
Grosse Cotelee
Hellfrucht
Matina
Zogola

Here is some info one each wild type as far as desirable traits

L. cheesmanii

This species is found exclusively in the Galapagos Islands.
L.cheesmanii has provided several benifits to the common tomato. The first is the incorporation of a single recessive gene that codes for jointless pedicels. This is oftened used as a genetic marker. L.cheesmanii also can be used for its high vitamin C, pro vitamin A and higher soluble solids contents. The subspecies, L.cheesmanii subspp. minor, has the potential for salt and drought tolerance. This tomato is self pollinating and can easily except crosses from garden varieties.

L. hirsutum f. glabratum

easily accomodates self-fertilization and progeny do not suffer from inbreeding depression. It is found in the southwestern parts of Ecuador at lower latitudes (0-6 degrees south). This subspecies is capable of crossing with L. esculentum.

L. hirsutum has been noted for several resistances to pests. One trait is that of resistance to two species of red spider mite. This is a physical rather than a biochemical mechanism. Mites become tangled in sticky substances which are secreted by the glandular hairs (trichomes). L. hirsutum also has a high concentration of a naturally occuring pesticide, 2-tridecacone, in the plant. This provides a high degree of protection against aphids and lepidopteran larvae (caterpillars).

L. hirsutum has also been a source of resistance to pathogens such as early blight (PI 126445), bacterial speck and root-knot nematodes

L. peruvianum f. glandulosum

As far as disease resistance goes:
Tomato spotted wilt virus - Lots of research projects documenting strong resistance to TSWV
early blight
leaf mold
fusarium wilt
septoria leaf spot
nematodes

It is also reported to have some insect resistances but most of that research is in South American countries so not sure how much of that would apply.

Forgot to add that drought resistance and also some frost resistance has been noted in some research I have read but the results were inconsistent.

F1 hybrid with a red tomato as the parent from what I have read usually produces green to greenish yellow fruits and some yellow and orange fruits, F2 green, yellows, oranges and possible red fruit. F3 is were the purple or bluish trait tends to show up.

Size wise the f1 fruits when parented by a commercial type tomato tend to be larger than the Wild Peruvian fruit. In F2 -F3 generations the fruit size and shape will vary.

Since the Wild Peruvian has to be used as the male parent a successful cross will be indicated by the wild type plant traits and growth habit its not in till further grow outs that cultivated tomato characteristics will appear. (note that selection of larger darker seeds will give more of the cultivated tomato properties)

For my possible grow outs resistance traits will be hard to realistically select for, So I will be using different factors: plant characteristics, Fruit color, size and shape leaf size shape, general health characteristics Self compatibility (The ability of the plants to self pollinate{This may require SIB crossing at the F1/ F2 phase}) Course taste will also be a factor as well.

Other possibilities for the crosses would be an OP root stock suitable for grafting at a reduced cost vs the expensive hybrid types on the market.

Also wanted to note that a lot of the information for crossing the Wild types and the trait information was found at kdcomm.net which is a great resource and learning site for tomato genetics

Sounds like a very interesting project :)
I have seeds for L. chilense, which I am planning to grow next year as a novelty.
Where did you get seeds for L. cheesmanii? I have been looking for the real deal for some time now,
but it seems to me that what most vendors sell is not L. cheesmanii. Most vendors shows a picture of
a orange/yellow (sometimes red) tomato with a pointed end. And as far as I know the real
cheesmanii is completely round, smaller and more hairy and "wild looking" (like the ones Keith Mueller is showing pictures of on his website)

got some of the wild species seeds at Trade Wind Fruits, will update once received on the packaging and service if you would like.

I will post the pics for each one as a reference for those interested.

first pic is of the L. cheesmanii
2nd pic is Lycopersicon glandulosum
3rd is Lycopersicon esculentum x peruvianum which is supposted to be a natural cross
4th is Lycopersicon hirsutum x esculentum

Also wanted to explain how some of the resistances work in the wild types as it was pretty fascinating. Some wild types have a mechanical defense, basically they have a compound that detects damage be it from fungus or bacterial canker that signals the surrounding tissue to die around the infected area to prevent the spread of the infection.

Just thought that was pretty cool

[QUOTE=DanishGardener;184922]Sounds like a very interesting project :)
I have seeds for L. chilense, which I am planning to grow next year as a novelty.
Where did you get seeds for L. cheesmanii? I have been looking for the real deal for some time now,
but it seems to me that what most vendors sell is not L. cheesmanii. Most vendors shows a picture of
a orange/yellow (sometimes red) tomato with a pointed end. And as far as I know the real
cheesmanii is completely round, smaller and more hairy and "wild looking" (like the ones Keith Mueller is showing pictures of on his website)[/QUOTE]
Here is an update to you DanishGardener that may explain why you are seeing reds and different L. cheesmanii being offered.

Fig. Leaves and fruits of Lycopersicon cheesmanii ‘short’ (a), L. cheesmanii ‘long’ (b), L. cheesmanii f. minor (c), L. esculentum ‘Gal cer’ (d), and L. esculentum var. cerasiforme (e). Scales in centimeters. Note that scales are not represented at the same magnification factor

[IMG]http://www.amjbot.org/content/vol91/issue1/images/large/abot-90-12-15-f02.jpeg[/IMG]

The main characteristics and differences between these wild forms are the following:

L. cheesmanii ‘short’ (Fig. 2a)—This type form was found only as coastal populations on cliffs and in open, undisturbed areas. Germination is slow, and in many cases, the seed testa must be excised to allow the radicle to emerge. The plants have pale green foliage and short internodes (2–4 cm), characteristics that persist even in good soil and uniform conditions. Leaves are pinnately compound with first- and second- order pinnate subdivisions. Leaves and stems are very brittle. Under our greenhouse conditions (40° N, Valencia, Spain), they do not flower from mid-November to mid-February. However, it is not known if this is due to the fact that this form requires a light regime typical of its region of origin (12 h light : 12 h dark) or that it flowers better in bright conditions of Spain's spring/summer. Ripe fruit color is orange-red.
L. cheesmanii ‘long’ (Fig. 2b)—This is usually found inland. Its foliage is darker than that of L. cheesmanii ‘short’ and has longer internodes (5–8 cm), similar to those of the mainland Eulycopersicon species. It germinates rapidly. Leaflets have small lobes. Leaves and stems are not particularly brittle. In our greenhouse conditions, it has flowering requirements similar to L. cheesmanii ‘short.’ Ripe fruit color varies from pale straw-yellow to dull orange-yellow.
L. cheesmanii f. minor (Fig. 2c)—Like L. cheesmanii ‘short,’ it is usually found in undisturbed coastal areas, has strong seed dormancy, has foliage that is pale green, and its internodes are short (2–4 cm). However, the morphology of the plant is very distinctive: leaves are three- to four-pinnate, leaflets are deeply lobed, all parts of plant are excessively hairy, stems are thick, and leaves erect. Flowering requirements are similar to L. cheesmanii ‘short’ and L. cheesmanii ‘long.’ Ripe fruit color is similar to the ‘short’ form.
L. esculentum ‘Gal cer’ (Fig. 2d)—This truly red-fruited form has not been reported previously in the Galápagos (Rick, 1956 , 1963 , 1971 ; Rick and Bowman, 1961 ; Rick and Fobes, 1975 ). Morphologically, these plants are very similar to L. esculentum var. cerasiforme, but fruits are much smaller (always <15 mm). They are found inland, in areas of high soil humidity in highly disturbed areas (road and trail margins, works areas, dumps, gardens). Like domesticated L. esculentum and feral L. esculentum var. cerasiforme, they do not need long (or bright) days to flower. The ripe fruit is deep red and is attractive to the Galápagos mockingbird (Nesomimus parvulus), which we observed carrying ripe fruits in their beaks.

Apart from these four wild forms, on the inhabited islands we also found cultivated (L. esculentum) and feral (L. esculentum var. cerasiforme) tomato. The feral tomato is found as a weed in vegetable gardens and trail margins. Galápagos accessions present the typical traits of this taxon (Fig. 2e).

There are important differences among L. cheesmanii, L. esculentum, and the wild continental species L. pimpinellifolium in the quantitative morphological traits measured in this work (Table 3). Internode length is much shorter in L. cheesmanii ‘short’ and L. cheesmanii f. minor than in the other taxa. Although there are not absolute differences in the size of the flower among the taxa, L. cheesmanii has a lower petal length to sepal length ratio than L. esculentum ‘Gal cer’ or L. pimpinellifolium (Table 3). Another remarkable feature of L. cheesmanii is that stigmas are only slightly exserted (always less than 0.4 mm), much less than stigmas of L. esculentum or L. pimpinellifolium (Table 3). There is also an important difference between L. cheesmanii and the other Eulycopersicon taxa in the flowering requirements. Although in their native environment and in other places at lower latitudes than Valencia, such as Davis, California (R. Chetelat, TGRC, personal communication), L. cheesmanii flowers all the year round if the conditions are favorable for plant growth and development, in the latitudes of Spain (40° N) they do not flower from mid-November to mid-February.

[QUOTE=Stepheninky;184924]got some of the wild species seeds at Trade Wind Fruits, will update once received on the packaging and service if you would like.

I will post the pics for each one as a reference for those interested.

first pic is of the L. cheesmanii
2nd pic is Lycopersicon glandulosum
3rd is Lycopersicon esculentum x peruvianum which is supposted to be a natural cross
4th is Lycopersicon hirsutum x esculentum[/QUOTE]

This is an update on the Trade Wind Seeds, everything was packaged very well (with one exception that I will go into later in the post) and all seed counts were in the 40+ seeds per pack. Each pack was $2 so when you take into account some of there seed are pretty hard to find (rare relative term I guess) so the pricing is pretty low. Seeds arrived Monday and were ordered 4-5 days ago so shipping was great.

The one packaging exception was that with Lycopersicon esculentum x peruvianum being such a long name the name was cut off. I was still able to figure it out as I knew what I had ordered so I guess it is a minor detail and will not prevent me from using them again in the future. Over all very pleased.

I would like to see a cross between Fred Limbaugh Potato Top and Cowlick and then the resulting F1 crossed with L. peruvianum f. glandulosum.



Minnies' Pinstripe crossed with Purple Hillbilly and resulting F1 crossed with
L. hirsutum f. glabratum


Chocolate Stripes crossed with L. cheesmanii and resulting F1 crossed with L. hirsutum f. glabratum


George

lol I will see what I can do though I will be focused on making single crosses.

Of the two wild crosses I already have I might try and do a grow out under lights this winter and hopefully I will be able to get some F2 seeds of them to move the project forward a little quicker so that I can grow them and anyone else that wants to participate can do a grow out as well.

Though yes I will try some of those varieties in spring and see if I can get viable seed, some of what you suggested I do not have seed for:

3rd is Lycopersicon esculentum x peruvianum which is supposted to be a natural cross
4th is Lycopersicon hirsutum x esculentum which is a hybrid F1

Those are the two I will try and grow out this winter to get some f2 seed for selection grow out.

Then in spring the varieties I have we can try and make some crosses to get F1 hybrid seed.

[FONT=Arial][SIZE=2]I kept waiting for one of the pros to respond to this, but since they haven't I felt like I should say something. I think you might be setting yourself up for a huge disappointment if all of your hybridizing efforts are placed here. Cross-species hybridization is at best very difficult. Some of these could be impossible. It would be like trying to breed a dog to a cat. There are examples of two species of tomatoes being crossed but you should know that not only is it rare, but the crosses that actually occur are quite often done on a large scale. Large as in dozens of flowers on hundreds of plants. It would not be out of the question to have 3000 to 5000 crosses before a successful fruit with seed is produced. I'm not trying to throw a wet blanket on your project, but if you don't have both a greenhouse and a place to grow 400 or 500 parent plants you're going to be a bit frustrated. If you are new to hybridizing you might want to try a few seasons of crossing two varieties of OP L. esculentum before jumping into cross-species hybridizing. I would also highly recommend that you pick up a text on plant genetics and breeding to help get a bit more understanding of what you are about to try and become familiar with the terminology and cell biology involved. I'm not saying it can't be done, but the odds against success are staggering for a home garden. I can't speak for all species of tomatoes but I do know that many other plants and animals that are the result of cross-species hybridization are sterile. It is possible that even if you get a cross to produce fruit, that fruit might not produce seed.[/SIZE][/FONT]
[FONT=Arial][SIZE=2][/SIZE][/FONT]
[FONT=Arial][SIZE=2]I think usually the approach of most breeding programs is to have a particular set of traits in mind and make crosses that would best show you the desired results. While it is not a rule set in stone, it is usually considered a good idea to use the plant that has the recessive traits as the female. Traits should be selected that you can either see (phenotype) or you have the ability to test for. If you don't have a scientific way to test for disease resistance then it wouldn't make sense for that to be a primary focus of your breeding program. There are several sources online for lists of dominate and recessive genes that you might find helpful.[/SIZE][/FONT]
[FONT=Arial][SIZE=2][/SIZE][/FONT]
[FONT=Arial][SIZE=2]I also have to say that grafting is darn hard to do and beyond the ability or desire of most home gardeners. I don't see how maintaining a root stock crop would be less expensive than purchasing a hybrid and I really don't know what one has to do with the other.[/SIZE][/FONT]
[FONT=Arial][SIZE=2][/SIZE][/FONT]
[FONT=Arial][SIZE=2]I hope you give some thought to at least trying some simple crosses of some of the varieties you have listed. Whatever you do, I wish you much luck.[/SIZE][/FONT]

Hey thanks for the advice, I am just doing it for fun and the learning experience of it. I expect plenty of issues with the whole thing but if it was easy it would not be worth doing. I am expecting that most of the crosses will probably fail on some of the wild ones and hoping for that one or two that will make it. I am planing on doing a few regular crosses as well. I have the two wild cross hybrids planted now for a winter grow. I have never seen so small of a tomato seed before and it matches the size of the wild ones. They have started to germinate will update this and the other post with pics once they are up a little more.

As far as the grafting goes I will probably do some experimenting with more common stock and the crazy glue method from the other OSU (Ohio State University) for their method you do not need any clips or special tools just a small brush, razor blade, and a tube of crazy or super glue. With that method it seals in the connection so the plant grafts quicker and there is less issues and less scaring of the main stem.

I will admit that with the pruvuium complex wild tomato types I am not expecting a whole lot for success, but I am hard headed and usually when I set myself up a goal I tend to achieve it eventually

Oh to answer the root stock question, What I am saying is that the current hybrid root stocks are expensive

Rootstocks widely used for grafting tomato are hybrids between tomato (Solanum lycopersicum), called intraspecific hybrid, or hybrids between tomato (S. lycopersicum) and a wild relative to tomato (such as S. habrochaites) called interspecific hybrid. Interspecific hybrid rootstocks are generally more vigorous but sometimes lack uniformity of germination/seedling emergence.

These are hybrids such as Beaufort, Maxifort, Mutlifort Johnny's Seeds is one of the few places that list them in a some what small quantity of 50 seeds for $21 That is what I mean by its a little expensive for the home gardener looking to try grafting. If an OP seed can be created that gives results to the home or small farmer wanting to try grafting then I think it would be worth it.

If you go to youtube and search for glue grafting it pretty interesting

Good luck on your experiments. As original said, you have chosen a difficult project. Crosses to L. hirsutum are possible. The others require a bridge species or another complex process.
The L. peruvianum cross you have planted certainly has wild genes - it is a monster plant. Flavor is a bit odd. I've grown a version of L. cheesmani and it was a small gold cherry like Coyote and oddly flavored as well. It's said Sara Galapagos is a stable cross.
Here are several photos from last year. The first is glandalosum (they get much larger), then an unusual hirsutum cross and the peruvianum cross I mentioned. Keep us posted.

Thanks, Those pics look awesome. Now even more excited to grow them as they all look very different for the usual tomato plants I am used to. With the straight L. Peruvian I am thinking of crossing it with the variety Current for use as a bridge. I talked to the director of the Genetics Research Center and he was unsure if that bridge would work but, I later found research from the Esol that had a project in Brazil where they had good success with that cross as a bridge so will have to see how it goes.

i love the leaf pattern of letter C. I find it very ornamental. :D

[IMG]http://www.amjbot.org/content/vol91/issue1/images/large/abot-90-12-15-f02.jpeg[/IMG]

Hello Stepheninky,
I read with interest about your comments on L.cheesmanii subspp. minor salt/drought resistance. I wonder if you tried both
L.cheesmanii
and
L.cheesmanii subspp. minor
to assess to what extent the subspp. minor is more tolerant.

Actually I am carrying out research on saline agriculture and I would like to try this variety in a series of trials.
I saw that there are some retailers that sell L.cheesmanii seeds, but I did not find any who sells L.cheesmanii subspp. minor.
Could you suggest a source for such seeds?

I have all the seeds you have gotten from tradewind fruits and have grown them over the last several years. They all were true to the pics but as I am not a wild tomato expert I can't tell you if they are the real deal. I have been doing alot with the cheesmanii and will be planting about 60 f3 gen plants this year. Last year everyone in my area was having problems with there tomatoes not ripening and low fruit sets. My f2's between a cheesmanii and a martian giant did better then everything else. I got them in late and not only did they catch up but they by far out produced every other tomato in my rented garden spot. The cheesemanii were the size of a penny and the f1 gen were the size of a nickle. I planted 50 f2 gen plants and got quite a variety of sizes and shapes. I am trying to breed a paste tomato with high beta carotene and a few other things. I would be real interested in your results and would also share some of my seeds if you are interested.
craig

You have lovely wild tomatoes.. I would try crossing Black cherry and Matina if I would be on your place. I have chesmanii seeds too, but I don't know which type, I'm going to try them this year, and maybe do some crosses too. :) Types c and d from your list have lovely leaves, and b nice fruit :) Mine is probably short type a. Working with wild types sounds very exciting to me, I will watch that tread.

Plant C does have amazing leaves. Do you happen to have a picture of a whole plant that you could share with us?

[QUOTE=doublehelix;185660][FONT=Arial][SIZE=2]Cross-species hybridization is at best very difficult. Some of these could be impossible. It would be like trying to breed a dog to a cat. [/SIZE][/FONT][/QUOTE]

I just wanted to clarify this general point about interspecific hybrids, although I don't have any information about these species in particular. It's true that reproductive isolation defines species. However, that barrier to crossing can take many different forms. There can be a geographic barrier between two populations that prevents any pollen from getting from one population to the other. The two populations can live in different habitats, or bloom at different times, or be pollinated by different vectors. All of these barriers to hybridization are very easy to overcome by a hobbyist.

There are other barriers that are harder to overcome, that require the massive effort and fancy equipment mentioned above. The barrier between species might be that fruit don't set, or abort early, or seeds don't sprout, or seedlings are weak and die young, or hybrids are vigorous but sterile, like mules. Try the crosses in both directions, because sometimes one works better than the other.

I am curious if the original poster could update his progress?

I am interested too and how some of the other crosses did. Mn Mato said he had some crosses also.

StephenInky, where are you? I'm still waiting for that update. Perhaps he got lost in his tomato field.

[QUOTE=ethane;473557]StephenInky, where are you? I'm still waiting for that update. Perhaps he got lost in his tomato field.[/QUOTE]

I just checked and he last visited Tville in September of 2014,

Carolyn

I have a lot of crosses with cheesmanii in them. The plants do well and I am still finding surprises in them. The one thing I am having problems with is recovering size. I think with backcrossing and the ideas some people here have given me that I can solve this problem. I have also fallen in love with S. hirsutum. The plants are some of the healthiest I grow and the one I have has the reddest red I have seen in a tomato. With such low genetic diversity in tomatoes there must be great discoveries to be found in wild tomatoes and fun in looking for them.

[QUOTE=Minnesota Mato;473652]I have a lot of crosses with cheesmanii in them. The plants do well and I am still finding surprises in them. The one thing I am having problems with is recovering size. I think with backcrossing and the ideas some people here have given me that I can solve this problem. I have also fallen in love with S. hirsutum. The plants are some of the healthiest I grow and the one I have has the reddest red I have seen in a tomato. With such low genetic diversity in tomatoes there must be great discoveries to be found in wild tomatoes and fun in looking for them.[/QUOTE]

How much success have you had with [I]L. Hirsutum x L. Esculentum[/I] crosses? Does it work any better with the wild species as the pollen donor or recipient?

All my crosses so far with the Hirsutum were made by someone else. I finally got a Hirsutum to try to cross myself this year. I do believe however it works better with the Hirsutum as the pollen donor.

[QUOTE=geeboss;185274]I would like to see a cross between Fred Limbaugh Potato Top and Cowlick and then the resulting F1 crossed with L. peruvianum f. glandulosum.



Minnies' Pinstripe crossed with Purple Hillbilly and resulting F1 crossed with
L. hirsutum f. glabratum


Chocolate Stripes crossed with L. cheesmanii and resulting F1 crossed with L. hirsutum f. glabratum


George[/QUOTE]

Why??

Steve, You are a pro.

[QUOTE=doublehelix;185660][FONT=Arial][SIZE=2]I kept waiting for one of the pros to respond to this, but since they haven't I felt like I should say something. I think you might be setting yourself up for a huge disappointment if all of your hybridizing efforts are placed here. Cross-species hybridization is at best very difficult. Some of these could be impossible. It would be like trying to breed a dog to a cat. There are examples of two species of tomatoes being crossed but you should know that not only is it rare, but the crosses that actually occur are quite often done on a large scale. Large as in dozens of flowers on hundreds of plants. It would not be out of the question to have 3000 to 5000 crosses before a successful fruit with seed is produced. I'm not trying to throw a wet blanket on your project, but if you don't have both a greenhouse and a place to grow 400 or 500 parent plants you're going to be a bit frustrated. If you are new to hybridizing you might want to try a few seasons of crossing two varieties of OP L. esculentum before jumping into cross-species hybridizing. I would also highly recommend that you pick up a text on plant genetics and breeding to help get a bit more understanding of what you are about to try and become familiar with the terminology and cell biology involved. I'm not saying it can't be done, but the odds against success are staggering for a home garden. I can't speak for all species of tomatoes but I do know that many other plants and animals that are the result of cross-species hybridization are sterile. It is possible that even if you get a cross to produce fruit, that fruit might not produce seed.[/SIZE][/FONT]
[FONT=Arial][SIZE=2][/SIZE][/FONT]
[FONT=Arial][SIZE=2]I think usually the approach of most breeding programs is to have a particular set of traits in mind and make crosses that would best show you the desired results. While it is not a rule set in stone, it is usually considered a good idea to use the plant that has the recessive traits as the female. Traits should be selected that you can either see (phenotype) or you have the ability to test for. If you don't have a scientific way to test for disease resistance then it wouldn't make sense for that to be a primary focus of your breeding program. There are several sources online for lists of dominate and recessive genes that you might find helpful.[/SIZE][/FONT]
[FONT=Arial][SIZE=2][/SIZE][/FONT]
[FONT=Arial][SIZE=2]I also have to say that grafting is darn hard to do and beyond the ability or desire of most home gardeners. I don't see how maintaining a root stock crop would be less expensive than purchasing a hybrid and I really don't know what one has to do with the other.[/SIZE][/FONT]
[FONT=Arial][SIZE=2][/SIZE][/FONT]
[FONT=Arial][SIZE=2]I hope you give some thought to at least trying some simple crosses of some of the varieties you have listed. Whatever you do, I wish you much luck.[/SIZE][/FONT][/QUOTE]

Any updates on this? I was really hoping to see results of these crosses,some of them can be done easily,without having to overcome any crossing barriers.

I've tried several of these crosses over the last decade or so, and I can summarize my experiences.

Solanum pimpinellifolium. The domestic tomato probably originated from S. pim. or a close relative, and this cross is very easy. The F1 between S. lycopersicum and S. pim. is sweeter than either parent, and many of the supersweet cherry tomatoes probably have S. pim. in their ancestry.

S. galapagense. This is a relative of S. pim. with tiny yellow fruit. It is also easy to cross with S. lycopersicum. The F1 is sweet but has a bad off-taste that it gets from its S. gal. parent. You can find F2 and F3 plants that are still sweet but lack the off-taste, but I haven't fully succeeding in stabilizing a line.

S. cheesmaniae. Another yellow one from the Galapagos Islands. Easy to cross, but in my experience the F1 lacks the sweet taste you get with S. pim. or S. gal.

S. habrochaites. This is from another sub-group of the tomato family, and it is difficult to cross with S. lycopersicum. I have had one successful cross out of about 30 tries. The rootstocks bred by Syngenta all seem to be S. habro. If you let a rootstock plant grow instead of using it as a rootstock, you get a huge vine with fuzzy leaves and a distinctive smell. The plants are completely resistant to Septoria and some varieties are also resistant to early blight, as well as being resistant to just about every known root and stem disease. The fruits are about 3/4" and stay hard and green. Oddly enough, crossing green-fruited habrochaites with pink-fruited Brandywine resulted in orange fruit, an interesting example of what geneticists called epistasis (when you get a particular trait with a combination of two genes but not with either one separately). Apparently habrochaites is missing one of the genes on the pathway to orange pigment, and Brandywine is missing a different gene, but when you cross them the F1 has all the necessary genes and can make orange pigment.

S. peruvianum. Difficult. I had one apparently successful hybridization, but the F1 plants all seemed to be sterile as both male and female parents. One of the genes for blue fruit comes from peruvianum, so it must be possible to do this cross, but so far it is beyond my skill.

Fred