Here is an excerpt from a review with an interesting verbage on names. Plea=
se note one of the authors is the mother of AM
Roger T. Koide · Barbara Mosse
A history of research on arbuscular mycorrhiza
Received: 9 November 2003 / Accepted: 9 March 2004 / Published online: 16 A=
pril 2004
The giving of names
Frank (1885) gave the name "mycorhiza" to the peculiar
association between tree roots and ectomycorrhizal fungi.
A thorough discussion of the derivation of the word
"mycorrhiza", including the incorporation of the second
r is given by Kelley (1931, 1950). In another publication,
Frank (1887) recognized a distinction between ectotrophic
and endotrophic mycorrhizas, which included
at the time only ericaceous and orchid mycorrhizas. The
name for the arbuscular mycorrhizal symbiosis has
changed through the years. The symbiosis was once frequently
called "phycomycetous endomycorrhiza" to distinguish
it from the endomycorrhizal symbioses formed
between members of the Ericaceae or Orchidaceae and
higher fungi. The name "Phycomycete", however, no
longer carries any systematic significance. As previously
mentioned, Janse (1897) called the intramatrical spores
"v_sicules" and Gallaud (1905) called the other commonly
observed intracellular structures "arbuscules".
Thus the name "vesicular-arbuscular mycorrhiza" was
established and persisted until recently. The recognition
that not all fungi formed vesicles led to the proposal that
this symbiosis should be renamed arbuscular mycorrhiza.
This change is now widely accepted, but in some of these
associations the fungi may not even produce proper arbuscules
(Smith and Smith 1997). Moreover, one must
agree that some hosts of arbuscular mycorrhizal fungi do
not house the fungi in true roots at all, and therefore that
the name "mycorrhiza" is not correctly used in those
cases (Lohman 1927; Kelley 1931). If we continue with
the line of reasoning that dropped the "vesicular" from the
"vesicular-arbuscular mycorrhiza", we must also drop the
"arbuscular" and, if we wish to be more inclusive of associations
involving these fungi, we must also drop the "-
rhiza". We would then be left only with "myco-" and that
is useless. Perhaps "phycomycetous endomycorrhiza"
was not such a bad choice after all. We are having fun
here, of course, but it is interesting to note the continual
problem we have had with names. Although it is no
laughing matter, one might be amused to count the times
we have questioned what should even be considered a
mycorrhiza in the first place (Boullard 1982; Allen 1996;
Trappe 1996; Jones and Smith 2003; Massicotte and
Peterson 2003)!
The naming of organisms and the establishment of
their evolutionary relationships are of great importance in
any field of biology. At the 1974 Leeds meeting (Sanders
et al. 1975), the name Endogone was used by many in
attendance to describe the "phycomycetous endomycorrhizal"
fungi. Another outdated name for arbuscular mycorrhizal
fungi, Rhizophagus, was also in use at the time
and continued to be used until about 1977. Thus, as recently
as 25 years ago the nomenclature of the arbuscular
mycorrhiza fungi had not been firmly established.
The history of the naming of our fungi is certainly an
interesting one. Link (1809, cited in Gerdemann 1971),
established the genus Endogone. Tulasne and Tulasne
(1844) were the first to describe the genus Glomus, known
only from spore clusters found in the soil. No connection
to the mycorrhizal symbiosis had yet been suggested. The
Tulasne brothers considered Glomus to be closely related
to Endogone. Fries (1849) established the Endogonaceae,
placing it in the Tuberales, but the family was transferred
to the Mucorales by Bucholtz (1912). Dangeard (1896)
was the first to describe an arbuscular mycorrhiza, which
happened to have formed from poplar roots. He regarded
this as a disease and named the fungus Rhizophagus
populinus (Dangeard 1900), provisionally placing it within
the Chytridiales. In 1922 Thaxter revised the Endogonaceae,
placing the Glomus of Tulasne and Tulasne into
Endogone. He considered Endogone to contain both zygosporic
(notably Endogone lactiflua) and chlamydosporic
species, observing that at least one species apparently
produced both kinds of spores. In 1939 Butler, in
reviewing the identity of arbuscular mycorrhizal fungi,
classified them as probable imperfect members of the
Endogonaceae. He nevertheless accepted the name Rhizophagus
for such fungi because of the earlier naming by
Dangeard.
The extraction of spores from soil is necessary for their
classification. Routine extraction from soil was made
possible by wet sieving and decanting, a method commonly
used to extract nematodes from soil and adapted to
arbuscular mycorrhizal fungi by Gerdemann (Gerdemann
1955a; Gerdemann and Nicolson 1963). Mosse (1953),
Gerdemann (1955a, 1961, 1965) and Gerdemann and
Nicolson (1962, 1963) added more species to Peyronel's
(1924, 1937) existing list of Endogone, whose spores
could produce typical arbuscular mycorrhizas. Gilmore
(1968) further added to the list by describing six spore
types, E2–E7, found in pot cultures. All these "species"
based on spore type seem to have little in common except
that they produced aseptate multinuclear hyphae, extramatrical
spores, intracellular arbuscules or hyphal coils,
and could not be cultured. At this point it seemed time
to attempt some classification or method of recognition
of all arbuscular mycorrhizal spore types. Nicolson and
Gerdemann, both plant pathologists by training, decided
on the classical system with Latin names. Mosse (a plant
anatomist) and Bowen (an ecologist) attempted a more
descriptive system based mainly on spore wall structure
and color, and cytoplasmic characteristics (Mosse and
Bowen 1968). Nicolson and Gerdemann (1968) divided
the fungi into two groups of Endogone, one forming extramatrical
azygospores/zygospores arising from the tip of
a swollen hyphal suspensor but producing no intramatrical
vesicles, corresponding to the bulbous vacuolate and
bulbous reticulate types of Mosse and Bowen (1968), and
the other forming extramatrical chlamydospores and intramatrical
vesicles corresponding to the yellow vacuolate
and red brown laminate spores of Mosse and Bowen
(1968). There was thus some correspondence between the
two attempts at classification. Because spores possessed
so few distinguishing features, which were frequently
affected by age and environment, the naming of new
species became quite a popular pursuit, but the E3 type of
Gilmore, which is quite common in nature, did not and
has not since found a home anywhere.
In the early 1970s it became clear to Gerdemann and
Trappe (Gerdemann and Trappe 1974) that Endogone,
which now contained a wide variety of species, needed
further revision. They split the old Endogone sensu
lato into seven genera including Endogone, Modicella,
Glaziella (nonmycorrhizal genera), and four mycorrhizal
genera including Glomus (which they resurrected, and
which had also previously been referred to as Rhizophagus),
a previously described mycorrhizal genus, Sclerocystis,
and two new genera Gigaspora and Acaulospora,
which corresponded to the honey-colored sessile spores of
Mosse and Bowen (1968). These were all placed in the
Endogonaceae, Endogonales, Zygomycetes.
Trappe and Schenck (1982) recognized another mycorrhizal
genus, Entrophospora. In 1987, Walker also
recognized five arbuscular mycorrhizal fungal genera,
having dropped Sclerocystis and added Scutellospora. In
1990, Morton and Benny placed the five genera of Walker
(1987) into three families (Glomaceae, Acaulosporaceae,
Gigasporaceae) and two suborders (the Glomineae and
the Gigasporineae), both of which were then placed in a
new order, the Glomales. Later, Morton and Benny (2001)
recognized two other families, the Archaeosporaceae and
Paraglomaceae, with two new genera, Archaeospora and
Paraglomus.
In 2001 Sch_ßler et al. used molecular data to establish
the relationships among arbuscular mycorrhizal fungi and
between arbuscular mycorrhizal fungi and other fungi.
The group of arbuscular mycorrhizal fungi was elevated
to the level of phylum (Glomeromycota), which was
shown to be as distinct from other fungi as the Ascomycota
are from the Basidiomycota. Little did the early researchers
know that they were studying an entirely new
phylum of fungi! The Zygomycota were shown to be
polyphyletic, and Endogone did not group near the
Glomeromycota nor did it group with the Mucorales.
Geosyphon pyriforme was added to the Glomeromycota,
which may have far reaching effects on our understanding
of the arbuscular mycorrhizal symbiosis.
The effect of continual revision of the taxonomy of the
fungi had an exasperating effect on many colleagues not
directly concerned with the taxonomy. Schenck (1985)
was sensitive to this issue and gave voice to the concerns
of many at the 6th North American Conference on Mycorrhizae.
His comments about this make amusing reading.
The methods employed by taxonomists have become
increasingly sophisticated. Initially, of course, taxonomies
were based upon morphological and anatomical characteristics
of the fungi. Later, methods based on serology
(Aldwell and Hall 1987), isozyme variation revealed by
gel electrophoresis (Hepper 1987) and fatty acid variation
(Bentivenga and Morton 1994) were introduced. Systematists
have come to rely increasingly on DNA-based
methods (Cummings 1990; Davidson and Geringer 1990;
Simon et al. 1990, 1992, 1993; Redecker 2000). While
DNA variation may be the best measure of genealogical
relationships among organisms, it is amazing the extent to
which anatomical and DNA-based methods have yielded
similar results. Routine identification of arbuscular mycorrhizal
fungi will probably continue to be based primarily
on structural characters and thus an increased appreciation
of the relationship between anatomy and DNA
will be important.
The ability to properly name the fungi, avoid duplication
of names and relate the species to one another
depends heavily on collections such as those held by
INVAM, the International Culture Collection of Arbuscular
and Vesicular-arbuscular Mycorrhizal Fungi, and
the BEG, International Bank for the Glomeromycota.
Schenck created INVAM in 1985. Since 1990 the collection
has been curated by Morton at West Virginia
University (
http://invam.caf.wvu.edu/). The BEG/IBG is
an international collaborative effort that provides registration
of individual isolates of fungi for research purposes
(
http://www.kent.ac.uk/bio/beg/). This will insure a
higher degree of certainty of the identity of the fungi in
use by researchers around the world."
--- In compost_tea_at_yahoogroups.com, Jeff Lowenfels <jeff_at_...> wrote:
>
> VAM is endomycorrhizal fungi....doesn't include ectomycorrhizal fungi, so=
the answer is a half yes!
>
> Jeff
>
> Sent from my ipad...Please plant a row for the hungry in your garden. Ask=
me how!
>
> On Apr 26, 2011, at 10:43 AM, "Stephen Steyn" <ssteyn_at_...> wrote:
>
> > Jeff:
> >
> > Is that the stuff they used to call VAM?
> >
> > SS
> >
> >
> >
> > From: compost_tea_at_yahoogroups.com [mailto:compost_tea_at_yahoogroups.com] =
On Behalf Of Jeff Lowenfels
> > Sent: 26 April 2011 17:01
> > To: compost_tea_at_yahoogroups.com
> > Subject: Re: [compost_tea] Re: Michael Martin Melendrez
> >
> >
> >
> >
> >
> > Evan, you mean mycorrhizal fungi...not mycorrhizae....the later is the =
relationship tween roots and fungi....the former is the fungi! Sorry, I am =
a stickler on this....even corrected Michael Melendrez during a lecture...=
..
> >
> >
> >
> > Jeff l
> >
> > Sent from my ipad...Please plant a row for the hungry in your garden. A=
sk me how!
> >
> >
> > On Apr 26, 2011, at 8:38 AM, "evanfolds" <evan_at_...> wrote:
> >
> >
> >
> > Agreed. I can provide some insight with lawns. We have a natural lawn c=
are company called A Natural Approach and have been in business for over 3 =
years. At first we used basically compost tea only, combined with bringing =
in bulk compost and soil testing to balance mineral ratios.
> >
> > Based on results, over time we have moved to less compost tea up front,=
and more humates and myccorhizae. We have found that if the soil is not re=
ady to build a soil food web that compost tea is not as effective up front.=
One of MMM's points. Mycco's don't need healthy soil to thrive, only the p=
lant to feed off of. Humates catalyze the creation of healthy soil and incr=
ease the CEC to hold nutrients better when they are added each winter.
> >
> > I think this is where MMM. I would add "energetic" to the healthy soil =
scenario Mike gave. It is often overlooked because we do not learn about it=
in school, and many times it is unmeasureable and unobservable except thro=
ugh results, but is vital in creating synergy amongst the physical, mineral=
, and biological components of soil.
> >
> > BioDynamic Ag respects this factor. Many BD farmers question the need t=
o "brew" tea in the first place. Using a vortex to potentize the solution, =
and the BD preps BD500 and BD501, one can stir for an hour and use homeopat=
hic dilutions to effect large tracts of land. The BD preps are putting out =
the precursor pattern energies of the microbes and inviting them in to live=
, rather than growing and distributing.
> >
> > Sounds TOO simple, until you try it and experience it. ;)
> >
> > --- In compost_tea_at_yahoogroups.com, "mikethewormguy" <mikethewormguy_at_> =
wrote:
> > >
> > >
> > >
> > > BC,
> > >
> > > Based upon my experience with the PROCESS called 'activated compost t=
ea' I would agree with MMM on the issue of 'garbage in / garbage out'. It t=
akes alot more that the use of one tool, like ACT, to bring about a change =
in soils/plants.
> > >
> > > I think what MMM found out, over time, is using only one PROCESS base=
d tool will not bring about the positive changes that he sought. He needed =
a more combined approach.
> > >
> > > You need a combination of physical, biological, chemical, delivery, a=
nd timing approaches to bring about effective positive change to soils/plan=
ts.
> > >
> > > Why limit yourself to using only a hammer....... ?
> > >
> > > My 2 cents......
> > >
> > > Mike Flynn
> > > Green Quest LLC
> > > BioSpecific LLC
> > >
> > >
> > >
> > >
> > >
> > >
> > > --- In compost_tea_at_yahoogroups.com, "barley.corn" <barley.corn_at_> wrot=
e:
> > > >
> > > > I have just read the comments from MMM in this months ACRES magazin=
e about compost tea. He seems pretty damning about its effectiveness. I was=
just wondering why he seems to have had such bad results after all the wor=
k that he did with it, and whether others are starting to share his views?
> > > >
> > >
> >
> >
> > No virus found in this message.
> > Checked by AVG - www.avg.com
> > Version: 10.0.1321 / Virus Database: 1500/3597 - Release Date: 04/25/11
> >
> >
>
Received on Tue Apr 26 2011 - 16:54:13 EDT