Micro dwarf x Indeterminate cross ideas.

[KaguyaCloud]

Update: 10/4/24
The red F2 is not great tasting. There are some that were sweet, but they mostly had the typical bland micro flavor to them. I have gathered enough seeds from the pale F2(around 80) and am starting to germinate the F3 generation to see if the dwarfing traits are stable. I'm starting off with 3 seeds. If flavor improves, stays consistent, or decreases, it'll let me determine whether or not this line is worth refining.

In addition, I have propagated a cutting of the pale F2 so that it can be crossed back with Rosella to restore some flavor and sweetness genetics. De-masculating the flowers of the pale F2 is slightly easier due to the pistil being less delicate, but it's still quite hard to do.

I currently have a "legacy stock" of my breeding project consisting of Rosella, Joro F1, and the Joro Pale F2 cuttings that are in a separate shelf. They are in their own labelled 4 inch pots and I occasionally prune back the indeterminates to maintain a small size.

[KaguyaCloud]

Update 10/13/24:


After further analysis of the shoot architecture of the Pale/White fruiting Joro F2 plant, there's a lot of interesting growing patterns. Micros, from what I've observed, skip the vegetative phase of all of their axillary shoots. This means that their axillary shoots/suckers immediately grow 3 leaves and a flower truss instead of growing 7-14 leaves followed by a flower truss.

As we know from the previous observations, the pale F2 immediately terminated after 2 true leaves have grown with no flower truss. However, the stem and leaves that grew before terminating seem to only produce primary micro-dwarf shoots instead of the regular micro axillary shoots. Those primary micro shoots then only produce micro axillary shoots, which is quite strange. The diagram I have made shows only two shoots, but there are at least 4 primary shoots that have grown on the actual plant.

This may suggest that there is a gene that suppresses the vegetative phase of the axillary shoots, which for some reason was not fully suppressed in the first two leaves of the F2. How strange, it may be possible that this vegetative phase suppression may be incompletely dominant in the presence of another gene(determinate?). This whole ordeal makes the early termination point of the seedlings even more suspicious, as some kind of conflict in the genetics or development happened during stem development as it grew.

[KaguyaCloud]

Update 10/22/24:


The F3 generation from the pale fruited F2 has finally sprouted. It seems that the seeds require around 24 hours in the freezer to sprout, which is a trait in the parent plant Rosella Cherry. First F3 seed that developed cotyledons exhibited long roots like normal sized tomato seedlings, which is not common in the micro dwarfs I have worked with. However, the cotyledons have not closed during the night cycle, which would indicate that there is a dwarf gene present. The second F3 seed that is in the process of germinating does have the smaller and characteristic hook shaped in the root system that is present in micros.

I have also included a picture of my legacy stock from this breeding project. At the moment it is quite easy to keep them alive and growing within the constraints of a 4 inch pot. Over time I hope I can fill the shelf up with the whole line of successive improvements. Backcrossing has been largely unsuccessful to perform on the pale F2, Rosella Cherry does not develop that much pollen from its flowers.

This marks almost a year since I've started the project(November 18) and I have pretty much grown about 4 successive generations(1 generation of parents, then 3 hybrid generations) at an extremely leisurely pace. Assuming I keep going, I should be able to get to the F7-8 by next year if I am able to figure out how to keep the flavor consistent. I will focus mainly on isolating the dwarf and early termination gene with flavor for the time being.

[bower]

My hat's off to anyone who can do crosses with those tiny micro flowers.
WRT pollen production, in my greenhouse situation there are very definite times of day to get pollen easily. Late morning to mid afternoon seems to be the window of opportunity, and a waste of time to try getting pollen earlier or later in the day.
YMMV in the indoor grow where light is constant, but worth a try.
Another thing about pollen, not every open flower is as ready and mature as another. I always try to collect pollen from more than one blossom on any given day. This means different stages of pollen maturity are present. Also I repeat apply pollen usually for three days, to make sure the mother part is also receiving pollen at the ideal stage of maturity.

[AKgardener]

Keep up the good work!!!

[KaguyaCloud]

Update 10/28/24:
https://imgur.com/a/joro-f3-update-Ghg8i7H
Out of the 3 seeds that were in the germination chamber, all of them at the very least sprouted roots.

Seedling Joro F3-1: Long roots. Stem before the cotyledons exhibit a dark color. No true leaves after the cotyledons, immediate jump to growing 2 axillary shoots. Although, these axillary shoots are possibly main shoots judging by the parent's morphology. I suspect that they will terminate to 2 flower trusses after a set number of leaves.

Seedling Joro F3-2: Abnormal seedling development. Small root size similar to micro-dwarfs. Stems before cotyledons are green. One cotyledon is very diminutive and the other cotyledon has 3 pointed ends. No sign of true leaves yet. Abnormal cotyledon shapes did occur during F2 selections, but none of the seedlings with the dwarf gene exhibited this trait.

Seedling Joro F3-3: Germinated. Extremely small root mass. No signs of leaf development yet.

Twin axillary stemming seems to be a heritable trait, which is quite interesting. I wonder if one of the genes responsible for micro-dwarfs involve termination of the main stem after the cotyledons, and maybe the leaf reduction gene causes the number of axillary shoots to grow to be reduced to 1 axillary shoot. It looks like longer roots could possibly be a recessive trait? Currently there are more seedlings with reduced root masses than long root masses during germination, could be a coincidence due to low sample size however.