New to growing your own tomatoes? This is the forum to learn the successful techniques used by seasoned tomato growers. Questions are welcome, too.
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April 7, 2014 | #1 |
Tomatovillian™
Join Date: May 2013
Location: Honey Brook, PA Zone 6b
Posts: 399
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Germination Test
I'm having some trouble with some seed of some of the varieties of tomato seeds I've received by trade this year. In particular, I'm having trouble with getting a breeding tomato variety, 97L97, to germinate. 97L97 is a descendent of L. cheesmani, which I understand is nortoriously hard to germinate. I had over 80 seeds, so I've attempted to design an experiment to use part of them. I don't have a solid idea of the seeds viability, but I wanted to design a test to see if different conditions aided or retarded seed germination.
Hypothesis: Different seed conditioning methods may aid or retard seed germination. All seeds will be started on damp paper towels stored in ziploc style sandwich bags. 4 seed preparation methods: 1) None (Control). Seeds from packet were placed directly on damp paper towel and sealed in ziploc (sealed bag is labelled). 10 seeds 2) Water soak. Seeds were soaked in tap water for about 9 1/2 hours, removed and placed on damp paper towel and sealed in ziploc (sealed bag is labelled). 9 seeds (one seed was lost after soaking). 3) Bromelain treatment. Bromelain is an enzyme (often derived from pineapple), that breaks down proteins. Back when I was briefly involved in rose breeding, it was a popular treatment to attempt to break dormancy on rose seeds. One advantage of bromelain vs. bleach is that oversoaking in bromelain does not seem to affect viability, while bleach soaking can kill seeds. One bromelain capsule was openned and the contents 'disolved' (it doesn't blend easily into water) into about 1/2 C H2O. I've had these capsules a number of years so my Bromelain may no longer be 'good'. Seeds were soaked for about 7 1/2 hours, removed and placed on damp paper towel and sealed in ziploc (sealed bag is labelled). 10 seeds 4) Bleach treatment. This is the method recommended by TGRC: http://tgrc.ucdavis.edu/seed_germ.aspx They recommend this for difficult to start seeds and even seeds that have been stored over-long. The seeds were soaked in 1 C of 2.7% bleach solution for 1/2 hour and then rinsed. They were placed on damp paper towel and sealed in ziploc (sealed bag is labelled). 10 seeds All seeds were started on 4/5/2014 -- though not all at the same time. Note: Since I had the bleach solution, after soaking and preparing the 97L97, I soaked CaroRich seeds (which I've also had problem with this year) and started 10 seeds of them on a damp paper towel. Possible results and problems: if none of the seeds germinate, I can pretty much assume my seeds are not viable. If however, all my seeds germinate, I won't know if what I did has an effect. I'm hoping to see a differential between my control and the treated seeds. I added a simple water soak after I designed my original experiment to try to eliminate the 'soaking' as a positive or negative variable in seed prep. One problem I realize is my sample size is very small. So if one type of treament yields 6 seeds germnating and the other 9, the sample size is so small I shouldn't overdraw the conclusion that one method is better than the other. As I check for results, I'll post the them to this thread. 1st Observation (4/7/2014): No germinations. Last edited by crmauch; April 8, 2014 at 11:27 PM. Reason: Corrected misspelling of Bromelain |
April 7, 2014 | #2 |
Tomatovillian™
Join Date: Feb 2012
Location: Newfoundland, Canada
Posts: 6,794
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Thanks for setting up this experiment, Chris.
Last year I was trying to germinate a few seeds of a lycopersicoides accession, and also at the time trying to start some old (?10 yr old) commercial tomato seeds. I read about the methods for old seeds and ended up trying a soak in dilute fish emulsion as this was reported the best method for old seeds. The old tomato seeds did germinate by this method but the lycopersicoides accession did not. Only one of the seeds put out a radicle but then failed to grow or shuck the seed and perished. This year using the TGRC method all 4/4 remaining seeds germinated. They had no trouble shucking their seeds. Cotyledons were slow to open up and one of the plants had very yellow streaked cotyledons. However all plants have developed normal true leaves and are thriving as well as the tomatoes. Looking forward to hear your results. |
April 7, 2014 | #3 |
Tomatovillian™
Join Date: Feb 2013
Location: Brantford, ON, Canada
Posts: 1,341
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I use a CD case and put the seeds between a paper towel and dampen with a food syringe, and place near heat about 75F. If no sprouts within about six days out they go.
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April 8, 2014 | #4 | |
Tomatovillian™
Join Date: May 2013
Location: Honey Brook, PA Zone 6b
Posts: 399
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Quote:
There are some 'interesting' tomatoes I'm trying this year and if I used the 'six day rule on the ones in the soilless mix, I would have almost no plants. 'CaroRich' (it's not the main tomato in my test, but it was also bleached came up after two weeks. I was concerned I 'overheated' the seeds so some of the recalcetrant tomatoes got more seeds placed in the pots (I usually use 4-packs for seeding and since I 'know' the seed is in the center. I can (mostly) safely plant an extra seed to one side of the planting area for each section of the 4-pack. One of my main goals is to see how bromelain stacks up against the bleach. I really don't working with the bleach, I've damages destroyed clothing before, and I know it can kill the seeds if the concentration is too high or two long. The bromelain is very slightly messy (what I have is in capsules), so I need to open the capsule and put the powder in the water. The powder doesn't mix well and tends to clump. But I don't feel like I'm taking any kind of risk. And hey, it's actually a good use for pineapple. Last edited by crmauch; April 8, 2014 at 11:28 PM. Reason: corrected misspelling of bromelain |
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April 8, 2014 | #5 |
Tomatovillian™
Join Date: May 2013
Location: Honey Brook, PA Zone 6b
Posts: 399
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2nd Observation (4/8/2014):
1) (Control) nothing 2) (H2O Soak) nothing 3) (Bromelain) nothing 4) (Bleach) nothing CaroRich (Bleach): 2 small radicle's showing I think there's mold appearing on some of the paper towels. If the evidence grows more strong, I'll replace the towels with fresh ones. Note: of the original 97L97 that I planted about 3/22 (not part of this test) - I have the first seedling up as of the evening of 4/8/2014 (17 days). And a puny weak looking seedling it is (so far). Last edited by crmauch; April 9, 2014 at 11:51 AM. Reason: Added update unrelated to direct test. |
April 11, 2014 | #6 |
Tomatovillian™
Join Date: May 2013
Location: Honey Brook, PA Zone 6b
Posts: 399
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3rd Observation (4/10/2014):
Transferred to new paper towels. 1 of the bleach treatment (97L97) seeds was lost. 1) (Control) nothing 2) (H2O Soak) nothing 3) (Bromelain) nothing 4) (Bleach) nothing CaroRich (Bleach): 1 seed w/ cotyledon showing 2 radicle's showing |
April 14, 2014 | #7 |
Tomatovillian™
Join Date: May 2013
Location: Honey Brook, PA Zone 6b
Posts: 399
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4th Observation (4/12/2014):
1) (Control) 2 Radicles 2) (H2O Soak) 3 Radicles 3) (Bromelain) Nothing 4) (Bleach) 2 Radicles CaroRich (Bleach): 1 seed w/ cotyledon showing 2 radicle's showing, 1 Long radicle |
April 18, 2014 | #8 |
Tomatovillian™
Join Date: May 2013
Location: Honey Brook, PA Zone 6b
Posts: 399
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5th Observation (4/14/2014):
1) (Control) 2 Cotyledons, 2 Radicles 2) (H2O Soak) 2 Coty 2 Long Rad 2 Radicles 3) (Bromelain) 1 Coty 4) (Bleach) 3 Long Rad CaroRich (Bleach): 2 Coty 1 Long Rad |
May 7, 2014 | #9 |
Tomatovillian™
Join Date: May 2013
Location: Honey Brook, PA Zone 6b
Posts: 399
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Last Observation (was taken 4/19/2014):
Unfortunately I have lost the specific records I was going to post here, but untimately all 4 categories (Control), (H2O Soak), (Bromelain), and (Bleach) had 3-4 seeds in various states of germination. Conclusions: 1) The trial needed to have larger numbers of seeds (20 seeds per category would be a start). 2) 97L97 seeds were not completely 'dead', but germination was < 50%. 3) Bleach definitely assisted in earlier germination, but I don't feel increased the total amount of germination. This needs further testing with larger numbers of seeds (see #1) 4) Bromelain was definitely a disappointment. In the past with testing against rose seeds I had definitely seen improvement due to Bromelain. I don't know if this is because my Bromelain is old, or the differences in seed coats (tomatoes are 'berries', and the seeds are 'simple', rose seeds generally require a cold treament, and the seeds are actually 'achenes' which means they have a 'hard' outer coating.). It might be worth testing further with Bromelain. |
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