Ethylene and rose seed germination?

General Discussion
1

Henry, I was browsing through your wonderfully informative web site and I saw your article about Ethylene and it’s possible application for rose germination. I’d been toying with the idea of tossing a ripe banana into a large ziplock bag and also enclosing some rose seeds to see what would happen. (Would one do this during stratification, or after?) Anyway, I was happy to see your article. You said you were using Ethylene but had no controlled results. The article was apparently written in 2000. Have you since been able to tell if it has been useful to you?

Alicia

Link: home.neo.rr.com/kuska/ethylene.htm

2

Hi Alicia, This past winter I have done a controlled experiment with ethylene (source Ethephon / Florel) with op seeds of Carefree Beauty and R. rubiginosa and applied it before stratification. I did the stats and it didn’t have an effect. Someday when I have some time I’ll write it up. Perhaps if different concentrations or application at a different time was used the results would be different. I’ve done an experiment looking at ethephon’s effect in seed germination with Heliopsis (a daisy) and applied it just prior to stratification and it helped a lot, even in some treatments without stratification is compensated for stratification. Anyway, for what it’s worth, it unfortunately hasn’t helped rose seed germination in the experiments I’ve conducted.

Sincerely,

David

3

I have not done any controlled experiments. I have looked at the literature at plants that may be similar to roses. This is what I found:

Title: Effect of ethylene treatment of germination of tweezers harvested seeds of two strawberry cultivars.

Authors: Yanagi, Tomohiro; Matsuda, Noriko; Okuda, Nobuyuki; Kosugi, Yusuke; Sone, Kazuyoshi.

Authors affiliation: Faculty of Agriculture, Kagawa University, Miki, Kita, Kagawa, Japan.

Published in: Engeigaku Kenkyu (2004), 3(3), pages 297-300.

Abstract: “The effect of ethylene treatment on the germination of tweezers-harvested seeds was examd. in two strawberry cultivars, ‘Sachinoka’ and ‘Asuka-ruby’. In both cultivars, seeds treated with 100, 200, 500 and 1,000 ppm ethephon soln. exhibited significantly higher germination rates than those of seeds treated with 0 ppm soln. However, almost all seeds treated with ethephon soln. exhibited abnormal root growth. In ‘Asuka-ruby’, the germination rates of tweezers-harvested seeds treated with 1,000 ppm ethylene for 24 and 48 h were significantly higher than those of control seeds. Thus, short-term incubation with ethylene is effective for increment of the seed germination rate, while the germination of tweezers-harvested strawberry seeds without any treatment remained poor.”

Title: Influence of cold and chemical treatments on the afterripening of apple seeds.

Authors: Colvis, Bernard E.; Mowry, James B.

Authors affiliation: Gerber Prod. Co., Fort Smith, AR, USA.

Published in: Transactions of the Illinois State Academy of Science (1969), 62(4), pages 425-9.

Abstract: "Seeds of 9 apple cultivars and 3 crabapple species were soaked in 3 concns. each of elgetol, ethylene chlorohydrin, gibberellic acid, and thiourea, in addn. to a distilled water check. After soaking, the seeds were stratified for 12, 8, 4, or 0 weeks at 4

4

Wow! If I understood that (and that’s not a certainty), then it sounds like I’d be better off NOT trying ethylene. The above abstracts indicated either decreased germination or abnormal root growth.

As a related question, I have seen mention of giberellic (sp?) acid being used. Where does one get this, how is it used, and is it worthwhile using it?

Thanks so much for the education, David and Henry!

Alicia

5

Giberellic acid is very effective on some seeds, not so much on others – and like any plant hormone, too much can cause problems, but it is a very interesting chemical, and well worth exploring. J L Hudson Seedsman (www.jlhudsonseeds.net) sells GA for use by home gardeners, and has some good information on how to use it, etc, so that might be a good place to start reading.

Joseph

6

Be very cautious with Giberellic acid. Experiment with rose seeds you don’t care about.

7

For those interested in using GA I found that the potassium based salt form which dissolves in water to not cause as much damage than the standard form which needs some ethanol to get it dissolved. I tested if GA helped germination in heliopsis and it didn’t. However, for my first experiment I used the standard GA3 dissolved in a little ethanol and it acually damaged the seeds some and resulted in less germination. When I got the potassium salt / water soluble form the germination was the same as the control suggesting GA didn’t have a significant effect. THe potassium salt form is hard to find. Thankfully a prof I know that is a biochemist had some. Drs. Carol and Jerry Baskins, leading world seed germination experts, suggested the potassium GA to me because of the often negative effect of the ethanol.

I’ve experienced the same thing with the auxin IBA in liquid form. When I use the potassium salt based one I’ve gotten better rooting with some species than the standard cheaper kind that needs some ethanol to dissolve it (smell dip 'N grow and you can tell there’s ethanol in there). It seems like with the conifer and some of the other cuttings (including rose) I’ve found this to be the case. It seems like the ethanol kills cells by the wounded end and helps make the remaining tissue more susceptible to rot.

Sincerely,

David

8

I have used Giberellic acid over 20 years ago and the germination did not improve and made things worse. Some seedlings were misformed, but I have no time to go into details.

Several RHA menbers, incl. myself, had written about their results in the RHA Newsletter at the time. It must have been in the late seventies or early eighties. Some oldtimers may remember about it. I am a member since about 1971/72.

George Mander