Does this paper support in situ allelopathic chemicals?

Tom Barr

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SpringerLink - Journal Article

Read it first........
Then read comments below.



Comments:

Sounds great and all................don't it?
But ground up chemicals isolated, then concentrated and added to the BGA does not mean it works in our tanks.
Also, we never have Microcystis aeruginosa, BGA is confined to two species that I've seen thus far out many samples and this is certainly not one of them:)

Ground up plant pigments are different than real world chemicals that are in a live plant in the water column.

While tempting to suggest a wider application in the field, this paper, nor any to date(note, this is 2006!) has ever shown in situ allelopathy in natural systems.

Other mechanisms such as NH4 uptake, stabilization, CO2 reduction, O2 productions and other processes due to macrophyte growth may be at play.

So the main points of the paper are not the applied use of this in an aquarium setting, the paper fails to offer support for that.

My goal here is to get the planted aquarist to be able to see such references often posted by other folks on forums and be able to decide if the information is useful under real world conditions. Then suggest issues with such references if misapplied, which is very often the case.

Then you get myths etc.

Regards,
Tom Barr
 

fresh_newby

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It is nice in the theoretical sense, and makes for good conversation, but cannot be applied to our situations, much like a lot of academia. I am a published author of many a microbiology paper myself, but I also am realistic to the fact that maybe 1/8th of the content written is applicable to real life sitations, although these types of observations pave the way for other things...and/or makes for good cat box liners :D
 

VaughnH

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This paper seems to me to be saying that the experimental results suggest that allelopathic chemicals may be present in some aquatic plants. I don't see how the results can be interpreted to go beyond that. I think it is good scientific technique to do things that concentrate the effect of chemicals, apply conditions most favorable to seeing the results you are looking for. But, then you have to accept that all you have done is show the possibility that your result applies in the real world, but you haven't come close to proving it. As I understand it, a lot of preliminary cancer research is done in that way.
 

Tom Barr

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I feel that many times, aquarist get a hold of a paper and think it has direct meaning.

"Oh look, this supports my contention!" when it does not really, it might suggest it, and it is worth discussing for our applications. I've not read any papers that had really anything we could truly use and I have plenty of controls that can be add to show they have little if any effect in our tanks, so it's dubious at best from what I can tell and observe.

Test wells vs real in situ effects are quite different.
Diana Walstad presented a nice table in her book on the chemicals and targeted organisms but the table did not tell intensity, what effect/mechanism of action, the concentrational dose (something extremely important in chemical control of any pest!! It's all about the dose!) but to a lay person it seems like strong evidence that allelopathy is likely.

Regards,
Tom Barr