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Re: Regulation of compost teas (was: NOSB loses its head)



        Soil microbiologists today typically are using estimates of 99 to
99.9 % of bacterial species in soil are not culturable "using standard
methods" (95 % is an underestimate).  Standard agar plate techniques appear
to give a biased and incomplete view of bacterial diversity in soil,
compared to the diversity observed with molecular DNA methods.  Species
diversity in composts is often observed to be much lower than in soil with
higher proportions of the species being culturable, probably due to the fact
that composts are rich nutrient media favoring bacteria that grow on rich
media, while soil is generally a carbon-poor medium, except for short
periods immediately after incorporation of composts, manure, crop residues,
or other organic matter sources.  Even though composts may have higher
numbers of total CELLS per gram, soils typically contain thousands of
SPECIES per gram, while composts typically contain only a few hundred
species per gram.
JBK


At 02:59 PM 10/22/2002 -0700, you wrote:
>Jeff Lowenfels wrote:
>> I am not sure Joel is right about 95% of soil bacteria not being
>> culturable......you mean you can't grow them in a petri dish? Where do you
>> get this statistic?
>>
>> I have my teas tested frequently and have seen the numbers. The biodiversity
>> is amazing and if that is only 5 % then so be it......though, again, I doubt
>> the percentage.... I would suggest Joel get in touch with
>
>Dr. Elaine Ingham
>Soil Foodweb, Incorporated
>info@soilfoodweb.com
>http://www.soilfoodweb.com/phpweb/
>
>or Dr.Eric Nelsonn (Cornell) to answer his questions.
>
>-
>See: GreenReleaf Novozymes
>http://www.bi-chem.com/green_releaf/professional/tech_info/tech_info_backgr
d.htm
> From their website:
>"Soil bacteria also manufacture a suite of trigger compounds that are
attractive
>to other soil microbes and when present in the rhizosphere this consortium of
>microbes can be extremely beneficial to plants. Plus, when beneficial bacteria
>colonize the root surface they can often help exclude pathogenic microbes from
>gaining access to the roots. Interestingly, when plants are grown under sterile
>conditions they often do not thrive as well as when the full microbial
community
>is present."
>
>--
>L.F.London
>lfl@intrex.net
>http://market-farming.com
>

*****
Jim Kotcon
304-293-3911 ext. 2230 (office)
304-293-2872 (fax)
304-594-3322 (home)
West Virginia University
Division of Plant and Soil Sciences
401 Brooks Hall, P. O. Box 6058
Morgantown, WV 26506

.