[crmauch]

Originally Posted by Fusion_power

This french document adds several steps to the carotene biopath. I found it very good reading especially since it quoted some of the documents above. See page 32 for details and 33 for a diagram. http://ethesis.inp-toulouse.fr/archi...1/grimplet.pdf

Unfortunately, I don't even come close in being able to read French.

Originally Posted by Fusion_power

Adding up all the available information, Jaune Flamme cannot have yellow, apricot, or tangerine. The only valid explanation is that it has a modified Cyc-B which does not convert all the lycopene into Beta Carotene. This explains the phenotype of the Jaune Flamme X Opalka cross. By extension, it implies a different Cyc-B for 97L97 which is much more efficient at converting to Beta. This explains the phenotype of the 97L97 X Opalka cross. This implies that a modified Cyc-B and Mo-B combined are the difference between 97L97 and Jaune Flamme. http://www.chem.qmul.ac.uk/iubmb/enz...erp/carot.html

There is only one thing that needs to be added. mo-b is recessive and results in 97L97 colored fruit. MO-B is dominant and results in fruit with roughly 50% lycopene and 50% Beta Carotene. Crossing MO-B (dominant form) with a normal red tomato would increase the amount of retained lycopene and decrease Beta Carotene levels but should give roughly the same total amount of carotenoids. http://hortsci.ashspublications.org/...2/387.full.pdf

Well what I said earlier was obviously off in that mo-b (converting the partial beta-carotene to all beta-carotine) is recessive. I see two possibilities (one very unlikely). Is there any documentation what mo-b does in absense of B? I'm guessing nothing?

I agree that the B in JF seems likely to be a less efficient at converting to BC. Would it still give the 90% BC in the presense of mo-B?

Breeding scenarios:
BreedingScenarios.jpg

I don't think the second scenario is true as I got orange tomatoes when crossing with 97L97 with both Opalka AND Heidi. Believing them to both have the recessive mob-B gene is just too unlikely.

See if this statement seems true:
In subsequent F generations of 97L97 if a plant is indeterminate is likely to be heterozygous for B (Bb). If it is homozygous (BB) it likely is to be determinate.

(The only way I see in my current scenario is to select for indeterminate and look for a plant whose subsequent generations throw no reds (or determinates)).

If 97L97 in heterozygous form (Bb) phenotype is orange, how would I, as a home breeder select for mo-B?

I'm now toying with the idea of going back to the breeding 'board', and crossing JF and 97L97. If there's a way to test for the presence of mo-B, then I could combine the non-linked B of JF with the conversion power of mo-B.