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Old September 24, 2010   #2
Stepheninky
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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

Last edited by Stepheninky; September 24, 2010 at 02:23 PM. Reason: add reference to http://kdcomm.net
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