Re: [compost_tea] Plant Defense Responce Pathways.
Hi Yield1:
I am curious about which plant pathogens you are referring to. I have used=
AACT to suppress powdery mildew on grapes and areas where I have foliar ap=
plied it show resistance (the sprayed plants do not get certain fungal outb=
reaks usually associated with weather conditions) in the limited time I hav=
e used it. I have not done an extensive multi-year experiment and am invol=
ved with one now so I will see how it works over a long period of time.
The plant pathogens -- I assume you mean extracts used for medicine -- woul=
d seem to be anti-fungals and bacterials in nature so they would be incompa=
tible with the growth of bacteria and fungi if applied during or at the end=
of the brewing process.
There may be a middle ground because correct brewing does create a great de=
al of aerobic bacteria. Our numbers from SFI on an early design mechanical=
brewer showed high bacterial counts but low fungal counts. We have since =
refined the brewing process.
So let's say that we up our bacterial caount 10 times to be conservative. =
A plant extract added to this mix and applied immediately (within an hour) =
might keep the extract active for what it does and not kill off so many bac=
teria that it renders the tea useless. I don't know if any tests have real=
ly been done on this level.
Compost made from certain primary plants might favor certain bacteria if in=
deed, the plant has some kind of antibacterial agent that is a byproduct of=
the plant. The bacteria that exist on that plant would be immune from the=
agent and would be available for growth in the brewing process. I don't k=
now if these bacteria carry any special property, other than resistance to =
the extract, that would make them more or less favorable when used, in a fo=
liar application, to resist the spread of harmful bacteria and fungi. But =
they would be alive in the tea and presumably enough would be alive when ap=
plied to outcompete certain bacterial/fungal diseases. Outcompete the dise=
ase and the disease has a far less chance to spread. Slowing the spread or=
confining it to a small area that can then be treated conventionally, save=
s the overall crop from massive applications of chemicals and adds to the o=
verall crop health. Eventually, it should be possible to reduce antibacter=
ial/fungal inputs to zero.
Ted Peterson
Earth-Wise/Spirit of the Earth
----- Original Message -----
From: hi_yield1
To: compost_tea_at_yahoogroups.com
Sent: Thursday, November 20, 2003 9:59 PM
Subject: [compost_tea] Plant Defense Responce Pathways.
So just exactly how does some CT brews suppress plant pathogens? It
has been suggested many times in this forum that it is simply numbers.
The fungi and bacteria when sprayed on the leaves overwhelm and out
compete most plant pathogens. Or could it be a more specific mode of
action that is responsible? Or has something activated the multiple
defense signal transduction pathways? 1 bacterial resistance pathway,
2 salicylic acid dependent pathway and 3 jasmonate/ethylene dependent
pathway? Causing an incompatible interaction, hypersensitive responce?
Have any real control studies been done? Has RNA been isolated and
analyzed to determine expression levels of these pathways or level of
gene expression? That is the sort of data I would be glad to embrace.
Direct undeniable plant specific response to product being used. Take
care hi_yield.
Yahoo! Groups Sponsor
ADVERTISEMENT
To unsubscribe from this group, send an email to:
compost_tea-unsubscribe_at_yahoogroups.com
Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
Received on Fri Nov 21 2003 - 16:23:42 EST
This archive was generated by hypermail 2.3.0
: Tue Feb 07 2012 - 14:14:52 EST