Propagation: Attempt to germinate very old Acer pentaphyllum seeds

I decided to try and germinate some old Acer pentaphyllum seeds I found in the back of my fridge and thought it might be worthwhile to document my progress (if any) here. It will encourage me to keep a journal of sorts to track my progress, and might provide a useful source of information for others attempting something similar in the future. (Whether it ends in success or failure is irrelevant, the information will have some value.)

There were ten A. pentaphyllum seeds stored dry in a coin envelope, in turn kept in a small plastic container on the back top shelf of the fridge. There was no date on the envelope but it is believed that they are from a batch of seeds received from Australia in late 2010 or early 2011, from the 2010 harvest. I previously germinated some of these seeds when they were fresh, and kept back this small batch as insurance against frost damage or similar to the original plants.

The seeds were soaked in water with a very weak solution of complete hydroponic fertiliser for 24 hours and 5 of the 10 seeds sank. They were additionally kept moist, but not under water, for approximately another 48 hours. The nutlets were then scored around the centre line with a sharp knife and split open using thumbnails. It was not surprising, given how many sank, that there were 5 viable looking seeds, the remainder included 4 that were empty and one that appeared to contain a dead seed. The viable looking seeds have now (05/03/22) been planted in small pots and are currently being kept indoors at around 20 degrees C. Some pictures of the samaras and seeds are posted below.

Here are the 10 seeds after soaking:


A typical empty nutlet:


The seed that appeared to be dead:


A typical viable looking seed:


The five viable looking seeds prior to planting (one still is in a half nutlet as he did not seem keen to fully come out of his shell):


To me, the seeds look viable, so we shall see what happens in good time. I will update when there is some news.

 

Please do ! I hope they are viable : if they were kept in the fridge, there's a chance...

 

ahh finally! someone using the excised method like me.. does wonders!

 

Yes, there were a number of reasons I used this technique here, mainly due to the age of the seeds:
- to see how many had kernals that looked viable prior to planting
- to guard against the aged seeds not retaining enough strength to split the nutlets open
- to potentially speed up germination.

None sprouting yet, but still very early days...

 

Have they been stratified? It appears you skipped straight from cold dry storage to sowing. Will it work?

 

I am hoping it will work.

The same batch of seeds germinated without issue and without extra stratification when fresh - I have a faint recollection of being told they may have spent some months on the ground before being collected, which would have approximated to stratification. If you look back at the pictures you can see the samaras are either partially or totally disintegrated on all of the seeds which would indicate some type of stratification, natural or otherwise.

They were also soaked and shelled prior to sowing, both of which actions would reduce factors that inhibit germination.

So, basically I am hopeful that germination will work in this way, but have no proof that my methods will achieve success. This thread is here as a record to see what happens, here's hoping....

 

AG3 helps a lot with old seeds. Gibberellins are directly involved in the control and promotion of seed germination; gibberellic acid (AG3) can break seed dormancy and replace the need for environmental stimuli, such as light and temperature.

 

If I don't get any germination after 2 or 3 weeks I will dig up the seeds and try either gibberellic acid or cold treatment or (most likely) both.

Not sure how being in the fridge for 10 years will have affected the need for cold stratification - I want to think it has negated it but not sure.

 

how do you make the ga3 solution? its pretty tough without something to weigh the powder

@zfrittz

@maf

 

I haven't used GA previously but I have noted the small quantities required, so have somewhat of a plan in place if I go down this route. Without lab grade scales you are unlikely to be able to weigh the small amounts needed, drug dealer scales are not going to cut it. I have some 10-15 mg plastic micro scoops I bought off ebay for another task and will just use those. Will not be super accurate but a lot better than trying to weigh small amounts of the stuff.

 

Or just buy a prepared powder from J.L.Huntsman.
Gibberellic Acid

 

i bought some from power grown. whats the difference with this sites ga3?

 

actually, nevermind. he has premade packages for a specific solution. very helpful! the 1000ppm solution im looking for is right there!

 

@0soyoung can i use vodka instead of rubbing alcohol to dissolve ga3 in water?

 

First shoot spotted today. It is just a white horseshoe breaking through the soil at this stage, a very welcome sight.

Hopefully I won't have to start messing around with GA3.

 

Nice! By white hroshoe you mean the maple seeds right?

 

Another question, what does the hydroponic fertilizer do to the seeds? Enzyme enrichment?

 

Yes, indeed one can.
But, note that buying laboratory-grade ethyl alcohol is cheaper because it isn't taxed as liquor.

 

The molar mass of ga3 is extemely similar to sugar. Could i just use the same process to measure sugar with ga3?

 

See pic below. Not sure if there is a technical term for this stage but it was white and shaped like a horseshoe so that is how I described it... this photo was taken a few hours after my original post and starting to get a little colour.

An old gardeners' trick to soak old seeds in multi purpose fertilizer (even miracle grow) prior to sowing, not sure of what it actually does apart from help ensure the seed is not deficient in any element. Similarly people soak seeds in potassium nitrate, KNO3, to aid germination so it might just be the nitrate boost that helps. Many Acer species have impermeable outer or inner seed coats so would not do much if that was the case - not sure where A. pentaphyllum is at in that respect.

 

The first one at cotyledon stage. They look a bit crumpled but not bad considering they spent over a decade wrapped up in a tiny seed.

I was impatient and dug up the other 4 seeds. 2 had the radicle showing and were replanted after a half hour soak. The other 2 I am leaving to soak overnight and if they have not swelled at all after 24 hours will assume the inner seed membrane is impervious and attempt to cut or scarify it.

 

How are they now?

 

A mixed bag.

The first one is doing very well - can make out the first true leaves starting to grow. Of the two that had the radicle showing, the one with the most developed radicle is now breaking the surface of the soil so that is good also.

For the last two, there was no sign that they were absorbing water while soaking, had to assume the membrane was fully intact and impervious to water. Rubbed the membrane on sandpaper to expose a little of the white underneath and soaked for another 24 hours. Hope I didn't overdo the soaking, one of them felt a little soft when I eventually planted them. Then one of the pots fell over and a good chunk of the very loosly packed soil came out! Got as much of the soil back in the pot as I could but couldn't see the seed amongst the similarly coloured medium, so just hoping that seed is not now buried too deep or, even worse, totally lost!

 

can i see a photo? @maf

 

Just nipped out to the greenhouse and took one. These two are currently spending the nights in the house and days in the greenhouse (if it is sunny).