Chironex

As a follow-up to these posts, here is a good description of the role ABA (abscisic acid) plays in seed germination and plants in general. Also, from the same website, a description of ethylene and its functions.

Abscisic Acid

Ethylene

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Scot

damaclese

Scot this may be a dumb question but as i know almost nothing on this subject all ask any way so when you do a embryo rescue are there still dormancies present in the embryo? and if so could you expose the embryo invetro to thees chemicals or would that be a bad idea?

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Chironex

Yes, the dormancy still persists even in the embryos, but I must thank you for bringing up this question.

Why? Because in making the more robust embryo rescue medium I was planning to use only kinetin, but now will also make some of the medium including both kinetin and ethrel to see if the synergism applies to embryos as well. This will highlight any advantages of having both chemicals in the medium versus only one.

Great input!

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Scot

damaclese

Your welcom thanks for all the hard work you are doing on behafe of the Banana world with famon being the nuber 2 consern for the world at larg any and all information pertaining to Muses increast production is a good thing

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Richard

Just a heads' up for the casual reader: Scot is an ace biologist whose thesis subject was the worlds deadliest animal, the Chironex.

Now Scot, you've peaked my interest here because you're discussing cotyledons and vegetables (lettuce) in the same thread. Lettuce seed is usually quick and easy to propagate. Did the research involve a cumbersome variety or was the lettuce being used as a model for "natural" germination?

Looking toward the future, I can see you as a hired gun for propagating some the unusual seeds I obtain from time to time.

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Chironex

Thank you Richard, but I must include that botany was only a few hours of elective credit (and that was 35+ years ago.)

Yes, it was on lettuce seeds, however, it is my belief that the process of germination and dormancy have similar characteristics in many seeds. So, while this is a shot in the dark, if it works we will have gained important knowledge to further our efforts.

As to the matter of propagating other unusual seeds, all we can do is try what works. Keep your fingers crossed, seat belts fastened and hope for the best.....

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Scot

Chironex

Update: Kinetin received today. Will prepare the medium this weekend for the more robust embryo rescue formula, AND will be setting up the soaks using ethrel/kinetin combination for recalcitrant seed germination testing. Will post updates as significant development occur. Thanks again to my chemist buddies out there, Remko (griphuz) and James (jmoore). I was correct on one of the formulas, but slightly off on the other. Your input helps scrape the rust off of this old brain.

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Scot

Michael_Andrew

I was looking over some experiments online and I think they were using ethylene with CO2.

Chironex

That is another experiment that I have read. It is a means of acclimatization without using sugar in the medium. It develops stronger plants sooner and with a higher state of vegetative development. I will be using this in further studies later on.

But, just in case you are reading something different than what I think it is, please email the article to me and I will read it.

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Scot

Michael_Andrew

Interrelations between Carbon Dioxide and Ethylene on the Stimulation of Cocklebur Seed Germination -- Esashi et al. 86 (1): 39 -- PLANT PHYSIOLOGY
Interaction of Carbon Dioxide and Ethylene in Overcoming Thermodormancy of Lettuce Seeds -- Negm et al. 49 (6): 869 -- PLANT PHYSIOLOGY
http://www.apsnet.org/phyto/PDFS/198...70n12_1158.PDF
www.scielo.br/pdf/sa/v61n2/19356.pdf
None of these look like the one I was reading but they do talk about it. I'll keep looking. The one I read gave charts and percentage of germination and days. I think the best rate and time was a combination of the ethylene and CO2. There were other factors and chemicals involved.

Michael_Andrew

Here is the one I was reading.

http://www.plantphysiol.org/cgi/reprint/56/6/826.pdf

Chironex

Interesting, thanks for bringing it to my attention. So, from what I gather, the synergy is formed when kinetin, ethylene, GA3 and CO2 are combined. Yet each shows little effect when used alone, with the exception of kinetin.

Therefore from least effective to most effective upon germination:

GA3 - no effect

Water + ethylene + CO2 - a light effect

GA3 + kinetin - maximum effect in the dark, but due to presence of kinetin

GA3 + ethylene + CO2 - improved germination rate under any light levels - needed for gemination

kinetin + ethylene + CO2 - improved germination rate under any light levels - not required to add the gases, but interaction improved germination rates

When GA3 and/or kinetin were combined with added ethylene, the need for added CO2 was eliminated. By the same token, when GA3 and/or kinetin was combined with added CO2, the need for added ethylene was eliminated.

These last two observations make it clear that the endogenous ethylene and CO2 gases present in the seeds/atmosphere are sufficient to maximize germination (overcome thermodormancy) in the presence of kinetin, or kinetin and GA3. In the presence of GA3 and kinetin, the need for supplemental CO2 and/or ethylene is reduced, but the 4 appear to work synergistically well to maximize germination rates.

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Scot

damaclese

wow it sounds like you are getting close to a good stable and reproducible conclusion Scot congrats. I'm just so excited to think that we mite be able to germinate any Musa seed that we want to!!!!!

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Chironex

Ok, today the modified medium was prepared and next the soaking medium will be prepared. I don't have a cheap source for CO2, so maybe I will just open a can of soda and put it in a zipper bag with the seeds and the soaking medium. (just kidding, but one never knows)
The modified embryo rescue medium will be described further under its own thread.

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Scot

Michael_Andrew

You can make your own CO2 with some water sugar and yeast.
DIY Yeast CO2 - The Planted Tank

Better yet start some wine fermenting!

Chironex

Interesting thought, I might have to use it.

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Scot

Chironex

This morning (12:00 a.m.) I initiated seeds into the kinetin/ethrel medium. While they probably will not germinate as quickly as the lettuce seed that was used in the research, it is hoped that this method will reduce the period of time and increase the germination percentages of banana seeds.
I set up 6 plates, each containing 8-12 seeds.
These are the seeds initiated:
M. ingens
E. perrieri
M. acuminata ssp. banksii 'Higa'
M. balbisiana
M. aurantiaca
M. paradisiaca var seminifera 'New Bhutan'

I will continue to monitor these plates and advise if there are any significant findings.

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Scot

griphuz

I take it you also have a control-group right Scot?
Kind regards,
Remko.

Chironex

I have many control groups! lol Actually, yes I also set-up the seeds in another plate with water only.

Wouldn't it be great if this actually does what it suppose to do? I think I will set-up a CO2 generator and try to adapt the petri dishes to allow some CO2 into them. I need to find some very small tubing, perhaps aquarium sized tubes and fittings could somehow be installed. Anyone have any ideas how to do this? The petri dishes are polycarbonate, so they will easily fracture. I think I will have to melt a hole for a fitting. Then connect it to a gang valve coming from the CO2 generator. Like an octopus rig.

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Scot

Chironex

Update, I read some research articles that indicate some have a dormancy factor within the embryo and others do not. So, I guess it wouldn't hurt to try this on embryos that do not respond otherwise, just to see if it has any effect.

I also read some research that indicated successful pollination of triploid bananas by diploid pollen! The one that was used as an example where it worked was Yangambi KM-5. Most of the positive results were with plantain types, however. But this is perhaps some good news that I stumbled upon by accident.

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Scot