Okra hybrids

[Tucson Grower]

Back in 2021 I crossed 'Star of David'  (SOD) with 'Alabama Red' (AR), so I made SOD x AR and the reciprocal AR x SOD. I looking at these seed packets and wondering how they'd do, so I've been working on getting some of them to germinate. I'm definitely needing to refrigerate or freeze storage more of my seed. After scores of seed, I may have finally germinated one of each.

[hedgeapple]

How did you cross these?

[Tucson Grower]

I had several plants of each growing in adjacent pots. I always tended them before the pollinators were active, usually even before the flowers opened, each morning. The flowers of these two varieties opened at slightly different times; but closed and dropped their corolla's at about the same time. If I didn't water them then (early in the morning), and several other times each day, I wouldn't have had any living okra plants. I manually transferred the pollen from a selected male flower, to the chosen female flower, then gently sealed the female flower with a hair-clip as per heavy hitter okra's description. Female flowers were not used as pollen donors, only as pollen receivers to limit any potential unwanted interference in the process, from their own pollen becoming unintentionally dislodged. I am aware of "emasculation"; by mechanical means, chemical, and genetic. In this instance, the unsuccessful creation of AR x SOD, may have been masked due to the red gene known to exist in the AR strain, but that wouldn't be possible for the SOD x AR cross, since SOD carries no red gene, and it is known that the gene for red pigment in okra is dominant. Hence, any seedlings produced from F1 hybrid SOD x AR exhibiting red pigmentation, are either that hybrid, a cross with another red pigmented variety or a novel mutation.

A similar benefit can be experienced when I'm producing the F1 cross for my attempt to introduce red pigment into the 'Heavy Hitter' strain of okra. I plan to focus most, if not all, of my hybridizing efforts, transferring SIR (Sea Island Red) donor pollen onto female HH (Heavy Hitter) seed bearing plants. In growing out the seed from this F1 hybrid generation, any and all seedlings which show no red pigment - will be culled. Which simply means they will be on the list of plants never to keep seed from. So they will have no progeny representing them in any future generations.

Already the selection process has begun. 4 or 5 out of 36 SIR seedlings have remarkably darker red pigmentation, in the petioles and veins of their cotyledon leaves, much more strongly pronounced than any of their sister seedlings. I labeled these, as plants to watch, for potential as more fit pollen donors vs their sister SIR plants. I need to follow this observation, at least into the F2 generation, to see if this variation is heritable. So as I plant them out, I will give them special designations, and carefully track the seed produced using these SIR pollen donors, so I can see if this extra darker red pigment is passed to any of their offspring, when crossed to HH, when used as seed parents.

[hedgeapple]

The first three crosses I performed years ago were done without mechanical emasculation - each cross took without fail. I complicated the process by using emasculation only because I kept reading about it, wanted a guaranteed cross for all seed, and because I have a habit of making everything harder than it has to be. With okra the failure rate for emasculated pods is so high that I don’t think it is worth it.

Too bad we have to wait two years to see if we even have a cross we like! I’ll be growing out a couple of new F1s and two F2s this year.

[Tucson Grower]

I just tweaked that selection process. Of the 36 pre-sprouted seedlings, ten are slowpokes, they haven't finished emerging, so I can't evaluate them, yet. Out of the 26 fully emerged SIR seedlings (in this batch), 4 received a skinny orange marker. Those 4 have smaller, darker green cotyledon leaves, with noticeably darker red veins and petioles. There are another 4 who received a skinny white marker, their cotyledon leaves are noticeably larger, lighter green, with noticeable red coloration of their veins and petioles, but not as intense as those receiving the orange markers.

Once the earlier SIR seedlings, those already planted outdoors, emerge, I will bring them into this developing grading system.

[Tucson Grower]

Apr 1, 2023 21:37:24 GMT -6 hedgeapple said:

The first three crosses I performed years ago were done without mechanical emasculation - each cross took without fail. I complicated the process by using emasculation only because I kept reading about it, wanted a guaranteed cross for all seed, and because I have a habit of making everything harder than it has to be. With okra the failure rate for emasculated pods is so high that I don’t think it is worth it.

Too bad we have to wait two years to see if we even have a cross we like! I’ll be growing out a couple of new F1s and a two F2s this year.

I too, sometimes do that overcomplication thing, so I know what you mean.

I basically did the SOD x AR and its reciprocal, because I had the plants available, I wanted to see if I could get red into SOD, I didn't yet know that red was dominant, but AR does already resemble SOD, but without the red blush. But I had been thinking of trying for a red, 'Heavy Hitter'. It is nice that heavy hitter okra, is supporting my efforts.

I'm really hoping for a very dark red/purple; though I don't know if the genetics I want, exist yet. I think my best chance is to keep a close eye on the seedlings, select the darkest, reddest ones, otherwise I don't have enough space, resources, time, to eyeball enough material to identify/select the genetics I'm looking for. I'm just going to need to use those traits I do see. Use them to produce as much F1 seed as I possibly can, then sprout and select like crazy. Then do the same for the F2 and etc. If it looks like somewhere down the line it's weakening, i'll need to consider backcrossing to select F1's or possibly even new selected SIR. Now's where I wish I still had the facilities to hold select clones, in vitro, to reinsert select parents (from the past), if appropriate. Like breeding great-great-great grandchild back to an ancestor; to recapture lost genes.

As heavy hitter okra has said, breeding plants is way easier than animals. I think he's correct, but even doing so with plants can be a major effort.

[hedgeapple]

Here is a paper you might find interesting:

www.ncbi.nlm.nih.gov/pmc/articles/PMC8471371/#!po=14.3564

[Tucson Grower]

Nice paper, fits nicely with some of my hypothesis. Lots of interesting info. Thanks for sharing.

[hedgeapple]

Well, this year I am growing out one new F1 (decided on just one) which I created last year and among all five varieties planted four days ago it is the only one already popping its neck out all over the place.

Of course that does not mean that it will outperform any of the other varieties over time, but in terms of sprouting it is showing hybrid vigor. All seeds were soaked for the same period of time before planting.

[Tucson Grower]

I managed to get 6, SOD x AR plants started - every seed germinated. I misplaced the remainder of the AR x SOD seed, so working with it will need to wait. I have these 6 planted 3 to each of 2, 15 gallon plastic pots. They are certainly growing differently from either parent variety. They all still retain their seed leaves, and have branches forming from every node. They're only about 4 inches tall, so far, but already have buds forming. I've never seen okra so quickly get to branching, wow.

Edit: For comparison; I also have 3 SOD plants growing in a similar setup. These are sister seed to the SOD parent for these F1 plants. These F1 certainly seem to be exhibiting a good degree of heterosis (also called hybrid vigor).

These plants' foliage are extremely overgrown. For 4 inch high plants, their foliage is very dense and lush, the seed leaves, though buried in several layers of thick foliage still look as if they just came out of the testa (seed coat). Each node shows signs of producing a branch. I'm anxious to see if the fruit carry the red blush of the AR parent.

[Tucson Grower]

And more pics -->

[Tucson Grower]

These certainly show hybrid vigor: they're growing monsters. I hope they produce fruit half as well as leaves, branches and stems.

[Tucson Grower]

There is definitely a difference between 'Star of David' okra and the hybrid 'SOD' x 'Alabama Red'. They were all sprouted at the same time and the 'SOD' plants were planted out a week earlier than the F1 plants, yet the F1's are many times larger, and are fruiting earlier. They're also keeping more, juvenile leaves, longer, and branching more.

Pics--> (First is F1 plants, second SOD) Both are 3 plants in 15 gallon pots.

[Tucson Grower]

Updated pics --> 'SOD' x 'AR' - then 'SOD'