permaculture

[Lawrence London <lfljvenaura@gmail.com>]

On Sun, Mar 19, 2017 at 10:02 PM, Lawrence London <lfljvenaura@gmail.com>
wrote:

> On Sat, Mar 18, 2017 at 6:28 PM, Karl S North <knorth@binghamton.edu>
> wrote:
>
>> http://peakoil.com/consumption/researchers-make-discovery-
>> that-could-increase-plant-yield-in-wake-of-looming-phosphate-shortage
>>
>
> Brendan Niemira : USDA ARShttps://www.ars.usda.gov/
> people-locations/person?person-id=43393
>
> ....did research on red clover exudates (affecting soil microbiology?)
> increasing a plant's ability to uptake phosphorous.
> Maybe this was in some way connected to an increase in phosphate stress
> response.
> This was mentioned in several Sanet posts years ago. I think someone tried
> to commercialize production of this exudate.
>
> Contribution of arbuscular mycorrhizal fungi to utilization of
> organic sources of phosphorus by red clover in a calcareous soil
> http://pure.qub.ac.uk/portal/files/379209/Feng%20et%20al%202003.pdf
> Phosphorus deficiency in red clover promotes exudation of ... - NCBI
> <https://www.ncbi.nlm.nih.gov/pubmed/17260144>
> https://www.ncbi.nlm.nih.gov/pubmed/17260144
> by K Yoneyama - ‎2007 - ‎Cited by 221
> <https://scholar.google.com/scholar?oe=utf-8&um=1&ie=UTF-8&lr&cites=238862353653498900>
> - ‎Related articles
> <https://scholar.google.com/scholar?oe=utf-8&um=1&ie=UTF-8&lr&q=related:FAS7iwucUAP1EM:scholar.google.com/>
> *Phosphorus* deficiency in *red clover* promotes *exudation* of
> orobanchol, the signal for mycorrhizal symbionts and germination stimulant
> for root parasites.
> Phosphorus deficiency in red clover promotes exudation of ...
> <http://link.springer.com/article/10.1007/s00425-006-0410-1>
> link.springer.com/article/10.1007/s00425-006-0410-1
> by K Yoneyama - ‎2007 - ‎Cited by 222
> <https://scholar.google.com/scholar?oe=utf-8&um=1&ie=UTF-8&lr&cites=238862353653498900>
> - ‎Related articles
> <https://scholar.google.com/scholar?oe=utf-8&um=1&ie=UTF-8&lr&q=related:FAS7iwucUAP1EM:scholar.google.com/>
> *Phosphorus* deficiency in *red clover* promotes *exudation* of
> orobanchol, the signal for mycorrhizal symbionts and germination stimulant
> for root parasites.
>


A thread about this in the permaculture list:

[permaculture] Breeding plants in diverse communities may lead to more
productive plants

https://lists.ibiblio.org/sympa/arc/permaculture/2014-November/045377.html
Niemira's post was in the Usenet newsgroup, bionet.plants:

Article: 5512 of bionet.plants
From: niemirab at student.msu.edu
<http://lists.ibiblio.org/mailman/listinfo/permaculture>  (Brendan A.
Niemira)
Newsgroups: bionet.plants
Subject: Re: Mycorhizzae vs. Fertilizer
Date: Thu, 02 Mar 1995  11:04 est


For agronomic crops, you're talking about vesicular arbuscular
mycorrhizae (VAM), a symbiotic endomycorrhizal fungus.  These are
ubiquitous anyway, and
not very host-specific, so there is very little need to inoculate the field
in order
to introduce them.  The big trick is getting them to colonize your crop
plant to such an extent that fertilizer inputs can be reduced.  You can a)
build up the population in the soil such that even moderately active fungi
result in
heavy coloniazation, b) put something in the soil to stimulate the activity
of smaller populations to get heavy colonization.

Crop rotations have been shown to have a definite impact on the population
dynamics of VAM, and work is currently being done (by me, among others) to
determine how the different crop plants differentially select for certain
species of VAM among all that are availible in the soil.

Other workers have shown that certain natural, plant-produced chemicals can
stimulate the existing VAM to higher levels of activity.  These
chemicals were originally derived from red clover, a popular sequence in
crop
rotations.  This may shed some light on why rotations are effective
w/regard to VAM.


More:

[permaculture] mycorhizae thread - this gem of info: plant selection of
appropriate VAM's & VAM-stimulating natural plant
extractshttps://lists.ibiblio.org/sympa/arc/permaculture/2013-March/043074.html

There are more posts in this thread in the sanet-mg archives that this
forwarded post from me was included in.
There were replies with a lot more info on :
1) "determine how the different crop plants differentially select for
certain
species of VAM among all that are availible in the soil."
2) "that certain natural, plant-produced chemicals can
stimulate the existing VAM to higher levels of activity.  These
chemicals were originally derived from red clover"
[a group actually produced such extracts to make a marketable ag product
from]

More:

[permaculture] red clover extract that stimulates vesicular arbuscular
mycorrhizae - Google
Searchhttps://lists.ibiblio.org/sympa/arc/permaculture/2013-March/043077.html

<>

This seems to have to do with Alia's information about available phosphate
levels in soil regulating a host plant's colonization of mycorrhizal
fungi on its roots
resulting in increased phosphate uptake;
i.e. phosphate is a regulator of this process.
The article quoted below goes into this:
The regulation of arbuscular mycorrhizal symbiosis by phosphate in pea
involves early and systemic signalling events
http://jxb.oxfordjournals.org/content/62/3/1049.full

<>

http://aem.asm.org/content/57/2/434

Isolation and Identification of Vesicular-Arbuscular Mycorrhiza-Stimulatory
Compounds from Clover (Trifolium repens) Roots

Muraleedharan G. Nair1*,
Gene R. Safir2 and
Jose O. Siqueira2†

+ Author Affiliations

1Bioactive Natural Products Laboratory, Department of Horticulture and
Pesticide Research Center, and Department of Botany and Plant Pathology, 2
Michigan State University, East Lansing, Michigan 48824

ABSTRACT

Two isoflavonoids isolated from clover roots grown under phosphate stress
were characterized as formononetin (7-hydroxy,4′-methoxy isoflavone) and
biochanin A (5,7-dihydroxy,4′-methoxy isoflavone). At 5 ppm, these
compounds stimulated hyphal growth in vitro and root colonization of an
undescribed vesicular-arbuscular mycorrhiza, a Glomus sp. (INVAM-112). The
permethylated products of the two compounds were inactive. These findings
suggest that the isoflavonoids studied may act as signal molecules in
vesicular-arbuscular mycorrhiza symbiosis.




-- 
Lawrence F. London, Jr.
lfljvenaura@gmail.com
https://sites.google.com/site/avantgeared