Bleach Treatment for Tomato Seed Disinfection

[seaeagle]

Here is concrete proof that Bleach is an extremely effective way to disinfect seeds, more effective than fermentation alone.I don't use it because I have little or no problem with diseases.I almost couldn't find it again, found it last year when fermentation was being discussed in another seed saving thread.

PDF file and huge one - 43 pages.Here is the abstract for anyone who has difficulty downloading it.

http://www.tomatosolutions.ca/sitebu...les/tomdis.pdf

Tomato Seed Disinfection with Chlorine
Tomato Solutions
J. A. Dick and A. A. Dick
October 19, 2014
ABSTRACT
Chlorine is a commonly used disinfectant for tomato seed contaminated with the bacterial
pathogens causing canker, spot, and speck diseases. Previous research has attempted to
determine chlorine effectiveness by testing for the presence of the pathogen after treatment of
infected seed lots. Even with the most advanced techniques, the accuracy of these methods is
questionable, and can underestimate the potential for causing disease. In contrast, this research
tested the effectiveness of chlorine for disinfecting tomato seed by plating treated seed onto
potato dextrose agar to determine the percentage of disinfected seeds. The elimination of all
bacterial growth from seed including bacteria such as Bacillus with highly resistant spores should
indicate the efficacy of a treatment for the elimination of bacterial pathogens. Dry seed that was
previously extracted by fermentation could be effectively disinfected after pre-soaking in water
for 24 hours at a temperature inhibitory to germination, and then treating with 5000 mg/L
chlorine at 20°C at pH 9.5 for 60 minutes with constant agitation. The threshold level for
disinfection was 2500 mg/L of chlorine resulting in less than 1% infested seeds, but slightly more
than 0%. Oxidation of the seed coat by the hypochlorite ion was the main factor resulting in
disinfection, but an additional effect from the presence of low levels of hypochlorous acid was
also found.

And yes fermentation was used first, but fermentation alone doesn't have the success rate when using bleach along with it.Without going back and reading it, I think they just used fermentation to remove the gel coat.When using bleach with fermentation the success rate was over 99% disinfection.

[Worth1]

I think my city water alone has enough chlorine to disinfect seeds.

Worth

[seaeagle]

Originally Posted by Worth1

I think my city water alone has enough chlorine to disinfect seeds.

Worth

You might be on to something LOL.Lemon juice has also been proven to be just as effective as fermentation.

[Gerardo]

The fun part will be to get from 8.25% hypochlorite solution (household bleach) to 5,000 mg/L, and somehow figure out the constant agitation.

[carolyn137]

I see some problems from the abstract in post #1,it is an abstract but I would like to see controls,and what was Ided with the controls with no treatment.

I also looked up and have links fo pure lemon juice and what it contains,which led me to pectins and rotting tomatoes.

As it is,I've decided not to transfer any of those links at all.

As the British said in WWII

Keep Calm and Carry On.

Carolyn, the retired Microbiologist who does have a strong interest in studies such as the one given only by abstract,which is not the total story,as she knows very well from writing abstracts for scientific papers herself.

[seaeagle]

I meant to post the link, but was thinking to myself, no one will read it anyway, so subconsciously I probably omitted it.Sorry.A simple Google search with the title would have easily found it.Have fun reading if you haven't already. I added to Post Number 1

And here it is again

http://www.tomatosolutions.ca/sitebu...les/tomdis.pdf

[seaeagle]

Originally Posted by Gerardo

The fun part will be to get from 8.25% hypochlorite solution (household bleach) to 5,000 mg/L, and somehow figure out the constant agitation.

Thank goodness we have doctors and lawyers and PHD's here to figure out the tough equations

[clkingtx]

Originally Posted by seaeagle

Thank goodness we have doctors and lawyers and PHD's here to figure out the tough equations

Hint, Hint...........

[Cole_Robbie]

Originally Posted by seaeagle

Oxidation of the seed coat by the hypochlorite ion was the main factor resulting in disinfection

Interesting, given that there are many oxidative methods of seed prep.

[carolyn137]

Originally Posted by seaeagle

I meant to post the link, but was thinking to myself, no one will read it anyway, so subconsciously I probably omitted it.Sorry.A simple Google search with the title would have easily found it.Have fun reading if you haven't already. I added to Post Number 1

And here it is again

http://www.tomatosolutions.ca/sitebu...les/tomdis.pdf

I read it.

Lots of data using lots of variables,but I still don't see what I think is most important,and that's which specific pathogens were removed from the seed coat b/c that's what it's all about for most tomato growers.

It was adressed briefly I think in #14, but then mentioned only Bacillus,no species given, as being present, but off hand I can't think of any Bacillus species that are pathogens of tomatoes..

I can reread it again,if I have time,but honestly,when comparisons were being made beteen what was said to be older work,going back to the 80's,that didn't interest me at all.

And I did remember the name of the woman who had the contracts for Campbells and Heinz,and had several long phone conversations with her.Her name is Dr.Helene Dillard and she moved from the USDA station in Geneva,NY to Cornell in Ithaca,NY..

Carolyn

[seaeagle]

Which specific pathogens were removed?

Bacterial pathogens causing canker, spot, and speck diseases.

The threshold level for
disinfection was 2500 mg/L of chlorine resulting in less than 1% infested seeds, but slightly more
than 0%.

So I am assuming that somewhere around 99.8% of seeds were disease free after Chlorine treatment, so I don't see what difference it makes because for all practical purposes all the pathogens were removed.

Now a little bit about the company

Tomato Solutions conducts a comprehensive tomato breeding program with the objective of producing the highest quality hybrids for both processors and fresh market growers. As the company name implies, tomato breeding can be viewed as a way of providing solutions to the problems growers and processors face in providing competitive products to the marketplace. We have concentrated our research program on developing processing tomatoes which are used primarily for peeling. Improving case recovery by increasing fruit size and firmness as well as peeled color is a primary objective. Another objective of our program is reducing peeling costs by incorporating traits for easy peeling which allow for reduced lye concentrations and application times within the factory. Breeding hybrids which have easy peel removal eases pressures as the industry transitions from lye peeling to steam or hot water based peeling systems. This has the added benefit of assisting companies with meeting more stringent environmental regulations while allowing them to remain competitive. For diced and chopped products, hybrids with larger fruit size and solid interior structure enhance product appearance and recovery. Hybrids of varying maturities with tolerance to fruit breakdown due to disease, and the ability to withstand heat without softening improves the flow of tomatoes from the field to the factory. Early maturing hybrids as well as those with extended field storage capabilities extend the processing season, maximizing capital assets. A close relationship between breeder, processor and grower is necessary so that the combination of factors in which improvement is most desired can be emphasized in hybrid development. Our production process for seed emphasizes genetic purity, high germination and vigour, and effective seed treatments for control of bacterial diseases. The production facilities and research farm of Tomato Solutions are near Chatham, Ontario, central to the main processing tomato production area of Canada. At present, we have several machine harvest processing tomato hybrids as well as hybrids for roma fresh market. Additionally, we have an outstanding beefsteak hybrid which is much loved by many of our customers and friends alike. In organic tomato production, many of our hybrids are used for due to their unique ability to produce well without the use of fungicides. This is a natural result of breeding without using fungicides in our plots. Please contact Jim Dick or Adam Dick for further information on tomato hybrids. Export/Domestic Sales: 45% U.S./55% Canadian Processing/Fresh Market Sales: 85% Processing/15% Fresh Market Paste/Peeled: 16% of Processing for Paste/84% for Peeled Product

http://www.ic.gc.ca/app/ccc/srch/nvg...mpltPrfl&app=1

This company's biggest customers are Heinz and Con Agra so they probably know what they are doing.

What I found interesting and something I always wondered about is contained in this line.

" In organic tomato production, many of our hybrids are used for due to their unique ability to produce well without the use of fungicides. This is a natural result of breeding without using fungicides in our plots."

So does this mean that once you start using fungicides you are trapped into doing so ?They seem to imply this. I know I have never sprayed anything on mine and have little or no disease problems.

[ContainerTed]

Seaeagle, this information is a great find. Thank you for posting it. When I looked at the customer list for that company, I saw a lot of large corporations who make a lot of tomato products - products that I buy on a regular basis.

While I haven't read it completely for detail (and I will definitely do that), there is enough info in my skim reading to know this is the kind of info I've been looking for. It justifies my chlorox soaks that I do before starting seeds.

Great stuff. Well done, sir. Again, Thank You.

[seaeagle]

Originally Posted by ContainerTed

Seaeagle, this information is a great find. Thank you for posting it. When I looked at the customer list for that company, I saw a lot of large corporations who make a lot of tomato products - products that I buy on a regular basis.

While I haven't read it completely for detail (and I will definitely do that), there is enough info in my skim reading to know this is the kind of info I've been looking for. It justifies my chlorox soaks that I do before starting seeds.

Great stuff. Well done, sir. Again, Thank You.

Thank you ContainerTed.I thought of your method on Tatianas Tomatobase when I saw it and how similar your methods were to this method.

And also noting how you keep your plants disease free and with the method you use for disinfecting your seeds, I would strongly recommend buying seeds from your store for anyone who is concerned about tomato seed disease.

[carolyn137]

The first link you gave had only the abstract,with no mention of pathogens detected,so I went back to that one and fetched the other link which is

http://www.tomatosolutions.ca/

I was able to review their breeding worrk and varieties mentioned,but didn't have time to check to see where they named pathogens detected or who their customers were.So if you could help me with that I would appreciate it.

Thanks in advance,

Carolyn

[ContainerTed]

Here's the list I was referring to at this link.

http://www.ic.gc.ca/app/ccc/srch/nvg...mpltPrfl&app=1


Key / Major clients:

H.J. Heinz, Canada
Conagra Foods, Canada
Thomas Canning, Canada
Weil Foods, Canada
Sun-Brite Canning, Canada
Harvest-Pak Foods, Canada
Red Gold Foods, U.S.A.
Hirzel Canning, U.S.A.
B & G Foods, U.S.A.
Furmano Foods, U.S.A.