Has anyone bothered to try selective breeding on the different Jabos? I’m not talking about merely “This tree tastes a little better! I’d better propagate it”. I’m talking about intense, directed selection, with a goal in mind; be it by hybridizing, or with pure species lines. I know there are selected cultivars available in some places, but I wonder if even they can be improved upon.
I have a few ideas in mind, but I’m hardly in a position to test them out right now.
Breeding for thin tannin-free skin seems most attractive for consumption, but I bet they’d also be more susceptible to pests. On the other hand, thick tannic skins might require you to bite through and discard the skin, but it’d be safer from pests, and more desirable for productivity in that regard.
If adherence of pulp to skin is an issue, breeding for slip-skin might be desirable.
A freestone cultivar would probably be great for processing, and if combined with thin tannin-free skin (or thick, tannic, slip-skin), it’d probably be ideal for that purpose.
The larger-fruited species make me wonder if they can be bred into some sort of stone-fruit analogue.
Then there’s breeding for smaller seed size and better pulp-to-seed ratio. Precociousness is a sought-after trait (and ideal for selective breeding, which would take time). And then the traditional breeding goals of superior flavor, better productivity, disease resistance, vigor, and versatility of soil tolerance.
I’ve already seen a few species that display some of these traits, but I’ve yet to see a species that incorporates all of them (at least the non-conflicting traits).
M. aureana and M. cuspidata seem to both have thin, tannin-free skin, and M. trunciflora is low-tannin at least.
Grimal has thick, tannic skin and small seeds (does it have good pulp-to-seed ratio?); apparently, it, together with Trunciflora, seems to have the best flavor. I wouldn’t know if pulp adherence to skin is an issue (I’ve no direct experience with them yet), so I also don’t know which ones (if any) possess the slip-skin trait.
Cuspidata is freestone, but it’s small in size, and large-seeded.
M. coronata, M. cauliflora and P. edulis have the largest fruit, but they’re slow growing (at least P. edulis is), so not very good candidates for selective breeding (unless you could find or breed a precocious morph). Could one of the other species be bred for larger fruit size?
Cuspidata, the Red Hybrid, and the Vermelha Hybrid seem to be the most precocious. Vermelha is more precocious, but seems sensitive to the wrong soil conditions.
The Red Hybrid seems the best candidate for selection. It’s already fast, productive (almost everbearing), vigorous, and resistant to adverse conditions. Now the question is, what would it take to breed these traits into it, in the best possible combination? Simple selection, or maybe by involving more crossbreeding?