SoCal2warm

Admittingly, I'm not sure exactly how it works in bananas, but in triploid citrus fruits will certainly develop, it's just that those fruits will be "seedless" because nearly all the seeds will fail to develop.

(even when the variety requires pollination to set fruits, and this only applies to non-nucellar citrus varieties here which do not produce true to seed)

Gabe15

druss is correct on this, seedlessness and ploidy are not directly related. You could theoretically have a seedless, non parthenocarpic triploid in which the fruit do not develop.

The seedless citrus are still parthenocarpic, their lack of seed does not automatically mean the plant will form a seedless fruit. The act of forming a fruit still needs to be initiated and is genetically controlled. Normally in wild plants, when the ovules are fertilized after pollination, the growth of the young seeds trigger the fruit to also start growing. If no seeds develop, and the plant does not have another mechanism (parthenocarpy) to trigger fruit development in the absence of pollination/fertilization, then you would just be left with a withering nub of a potential fruit that will never grow.

It is an incorrect oversimplification to conclude that triploidy causes sterility which leads to seedless fruit. In the case of bananas, triploidy often lowers fertility and potential seed set, but it is parthenocarpy that allows a potentially seedless fruit to develop. Even parthenocarpic triploids will often set some amount of seed when pollinated however, just typically not as much as the most fertile diploids and tetraploids. And there are many reasons for sterility, not just ploidy level. There are sterile diploids, and fertile triploids as well.

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Growing bananas in Colorado, Washington, Hawaii since 2004. Commercial banana farmer, 200+ varieties.

SoCal2warm

Isn't it true that all eating quality banana varieties are triploid cultivars?

That would seem to imply triploidy has something to do with seedlessness...

druss

No, there are plenty of good eating quality bananas of diploids, i.e nine enano, inarnibal, terema, sucrier etc plus plenty of good tetraploids such as the fhia lines like goldfinger, plus other synthetics like calypso. Its true wild tetraploids are rare but they are around, from memory Gabe identified one on bouganville.

druss

Gabe, do you have a preference for method of hand pollination?

Gabe15

Definitely far from the truth. There are innumerable edible diploids, and in fact they are arguably the most diverse class of edible bananas.

We found two in Bougainville, but there are definitely a few others out there as well. And yes of course, many many synthetic tetraploids exist from breeding programs.

I have mesh bags I put around the male buds to prevent pollen contamination. I collect newly opened male flowers from the bagged buds early in the morning, usually around 6-7AM, then immediately use them to pollinate female flowers on other plants. If they are small female buds, you can also bag them to prevent insect or bird pollination, or you can pollinate the hands that are a day or two out from opening by gently lifting the bract, manually opening the female flowers to expose the stigma better, pollinating, and then closing the bract back over it, it kinda acts like a natural bag well enough.

If I'm working with highly fertile males with lots of pollen, its easy to basically use them like little paintbrushes on the stigmas. If there is not very much pollen, I sometimes slide the male flower over the stigma so that the anthers come in direct contact with the stigma along their entire length, thus getting more pollen.

In some male parents with very little or no visible pollen, you can sometimes still get some by gently scraping the anthers with a toothpick to manually open them and get a little bit of pollen on the toothpick which I then use to transfer to the stigmas of the female flowers.

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Growing bananas in Colorado, Washington, Hawaii since 2004. Commercial banana farmer, 200+ varieties.

Richard

Yes. But you need to take a step back, read the publications of my forefather Howard Frost, and try again.

University of California: In Memoriam, December 1970

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Back in business at plantsthatproduce.com

druss

Excellent, it appears that i will have a musa zebrina with male flowers at the same time as a goldfinger with female, think the goldfinger is female sterile but will practise anyway.

SoCal2warm

Apparently there are two different levels of causes for seedlessness.
Hybridization between different species, and triploidy.

https://bananaroots.wordpress.com/ta...anana-species/

Richard

You might want to follow Gabe15's education path to get up to speed.

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Back in business at plantsthatproduce.com

druss

Less seed and more flesh is not the same as seedless or parthenocarpic. This overview is incomplete It doesn't mention the initial subspecies of acuminata behind the initial edible bananas, then crossed with balbisina to give rise to new varieties though no true edible bb, bbb or bbbb exist. nor does it explain the fact that african edible bananas are from possibly a different domestication event. It fails to address the other interspecific hybrids like AS vunamami and ones with callimusa such as umbubu AAT or Yawa2 ABBT a three species 2 subgroup hybrid. Also for a long time ploidy was a judgement call, only now with flow cytometry can we know if assumed genetic id was right. Id work on the traits you want and let the ploidy sort itself out.

Gabe15

If you really want to begin to understand what you seem to want to know, start here:
https://www.abebooks.com/servlet/Sea...anas&kn=&isbn=

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Growing bananas in Colorado, Washington, Hawaii since 2004. Commercial banana farmer, 200+ varieties.

Gabe15

Hybridization aided in increasing diversity, and triploidy tends towards more vigorous and larger plants, but neither are directly related to seedlessness/edibility.

Seedlessness is a condition, not a trait. A plant may or may not be seedless depending on if it was pollinated or not by viable pollen. You can't tell if a banana is incapable of making seeds unless it is properly pollinated. The fact that you don't finds seeds in a given edible banana fruit doesn't really mean much as to whether or not it has the capability to produce seeds under the right conditions.

One of the most notorious seed setters among edible bananas are many members of the Pisang Awak subgroup, which are hybrid derived triploids. If pollinated, they can make so many seeds that it can really get in the way of eating the fruit normally.

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Growing bananas in Colorado, Washington, Hawaii since 2004. Commercial banana farmer, 200+ varieties.

druss

Slightly off topic, but Gabe I can only access the male flowers on the donor plant between 8sm and 5pm, can i pollinate in the evening? Or will the male flowers last until morning?

Gabe15

Try as early as you can, 8AM will probably still work, but pollen viability decreases as the day goes on. It is best to collect the male flowers and pollinate right away, if you have to wait, I would collect the male flowers and refridgerate them soon after planting, then pollinate the female flowers in next morning.

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Growing bananas in Colorado, Washington, Hawaii since 2004. Commercial banana farmer, 200+ varieties.

druss

Awesome thankyou, i dont anticipate any success with this cross but need to start practicing the mechanics.