trichoderma info

[zep101]

well, I haven't had the internet for a month since moving and the house I moved into "used" to be infested with mold that was dealt with professionally. there was mold growing in the basement after the fact on some brand new dry wall(only the paper) and it was thrown into the backyard where it sat for two weeks. at the same time, everything I was doing, no matter how sterile my actions, was getting green mold into it. after tossing all the gyprock and anything else near that had this green all over it(I wore a mask and gloves and sprayed it ALL down with bleach water) I got my internet up and running again. I haven't tried spawning anything else yet until I've thouroughly cleaned all my stuff upstairs. (washing all surfaces, clothing, tossing garbage all that jazz) I came across a large article on ****************************************.com that has ALL the info one needs for trichoderma contamination and how to increase yields. not sure if the same article is on mycotopia so I'll repost it to help anyone out. I take NO credit for this info but, just like the mold, I want to spread it around.

thanks goes to starspawn and Shu-Ting Chang Ph.D

[zep101]

I read a lot,and after i cleaned out my local libaray of everything from Stamets to mycology text books i started poking around the research area.Since nothing can leave from there i never bothered to check.Anyway i found a plain marked file labled mycology translated from china to english.So i start going through it,and it was mostly about mycorrhizal relations with plants,and other lower fungi like molds.Then i find a paper titled 'Mushroom Green Mold:and the role of spawn' by a Mr.Shu-Ting Chang who turned out to be one of the most respected mycologist in China.Well i ran a copy of it and typed it up.

Mushroom Green Mold

A number of imperfect fungi form on undercomposted substrates,which
still have high levels of easily available carbohydrates.This is very
common on composts that have been incompletely pasteurized.Species of
Trichoderma,Aspergillus,and Penicillium are most frequently encountered
and are sometimes referred to as "green molds".

History

Early studies reported that T.viride was the common species of
Trichoderma that was found as a colonizer of composts and a subsequent
inhibitor of mushroom mycelial growth.Hayes stated that its occurrence
was associated with excessive wetness and inadequate pasteurization,
which led to the incomplete transformation of nutrient materials
required for mushroom growth.Trichoderma koningii has been cited as the
causal organism for a disorder in the beds of Agaricus bisporus in
which there was an infestation of the mold on dead mushroom tissue left
in the beds.A spread of the mold over 15-to 20-cm-diameter areas of the
bed followed within 2 or 3 days.Although green mold disease is
primarily found in mushroom houses using a compost made up of such
things as straw,manure,cotton seed hulls,rice hulls,sawdust, ect.,some
of the mushrooms that are produced on wood may often be damaged by
Trich green mold.For example,Kuehneromyces mutabillis,now known as
Pholiota mutabilis,has been grown in Germany since the end of
world war 2 and is popular local mushroom where it's produced.This
fungus is grown on wood,and better and longer production is obtained
when the wood on which the fungus has been inoculated and is already
growing is placed for two thirds of itslength into bed soil.A few
months later the mycelium develops into the soil,from which it receives
water and nutrients.The bed soil is frequently covered with mycelial
mats of lower fungi including T.viride.The growth of these weed fungi
may have no effect,or they may impair growth of the mushroom by
utilizing the substrate.The bed soil technique is used in the
cultivation of other wood-rotting mushrooms such as Lentinula in the
early days of its cultivation and Dictyophora.Gramms reported that wood
covered by bed soil gave a threefold greater yield of K.mutabilis than
wood not inserted into soil.He suggested that the functions of the bed
soil are to provide humus and minerals for the mycelium,to provide
greater temperature and moisture constancy,and to absorb toxic
metabolites produced by the mycelium.These advantages apparently can
affect the potential damage produced by Trichoderma.
Ospino-Giraldo et al. gave a brief review of the early history of
mushroom green mold including the description of green mold given by
Sinden and Hauser in 1953.In the past,green mold occurred only
periodically,generally on farms using low-quality compost or employing
inadequate sanitation procedures.Thus,green mold was not a serious
problem when growers used good hygiene,and proper preparation and
pasteurization of the compost.In 1985,more severe outbreaks of green
mold occurred in Ireland mainly in bagged compost.It was also found in
England and Scotland with yield reductions as great as 30%.In Canada
and the US equally serious outbreaks of green mold occurred,and in
1994-1995 epidemies of green mold took place with crop losses in
Pennsylvania exceeding $20 million during a 3 year period.Green mold
had become a major problem in the mushroom industry and extensive
research was directed to studies of the causal organism and control
measures.

Research

The research reported here deals with studies of the role of spawn in
the disease,the expression of green mold following supplementation of
the compost,the use of molecular technologies to establish the identity
of Trichoderma strains involved in
the disease,and,finally,measures useful in control of the disease.

Role of Spawn

A number of significant findings were reported by Fletcher as the
result of his studies of mushroom spawn and the development of
Trichoderma compost mold Fletcher uses the term Trichoderma compost
mold in preference to green mold to distinguish between problems in the
compost and green mold occurring elsewhere such as:

(1)the wood of the trays or

(2)the remains of mushrooms left on the casing or

(3)the mold causing spots on the caps of mushrooms.

The initial study of Fletcher was designed to determine if Phase 2
compost(i.e.,compost thats been peak heated or pasteurized) can serve
as a medium for Trichoderma.It was found that Phase 2 compost did not
support the growth of T.harzianum even when high inoculum levels were
used,but that unspawned Phase2 compost did contain viable cells of
T.harzianum as revealed by the recovery of colony-forming T.harzianum
even when there was no visible evidence of mycelial growth or
sporulation in the compost.When the compost was spawned,and
subsequently colonized by Agaricus bisporus,the population of
T.harzianum was reduced to undetectable levels.In the absence of
Agaricus but with autoclaved wheat grains present in the compost,there
was an increase in the Trichoderma population.Thus,it was concluded
that cereal grains probably play an important role in the development
of Trichoderma compost mold,a finding that led to further
experimentation with the following results:

-Trichoderma did develope in compost when the inoculum was placed on a
food base such as autoclaved wheat grain,but not when placed on inert
materials such as perlite or vermiculite.

-When spawn and compost were inoculated with germinated spores of
Trichoderma,the germinated spores were unable to sustain growth on
Phase 2 compost away from the grain.However,it was found that small
pieces of grain were able to sustain growth of Trich on Phase 2
compost.

-When various concentrations of spores were applied to grain spawn,
Trichoderma developed on only the highest concentration.

-Temperature studies revealed that at 15C,Trichoderma can colonize
grains before the mycelium has formed a protective barrier,and also
that Trichoderma will grow at temperatures equal to or greater than 30C.
This is the result of a rapid decrease in growth of A.bisporus above
28C,and death of the mycelium is reported to occurat 32C,thereby
eliminating or diminishing the protective barrier.

-Differet isolates of Trichoderma were tested as to their ability to
inhibit growth of mycelium and there were marked differences among
the isolates listed.

When control of Trichoderma was investigated,it was found that
inoculated grain spawn treated with a 20-ppm solution of carbendazim
prevented the development of Trichoderma with no adverse effects on the
growth of A.bisporus.
A studie was performed to determine whether there was a requirement
for spawn grains for the establishment of trichoderma infection in
compost because earlier studies had implicated cereal grains in the
development of Trichoderma.Results of experiments performed by Rinker
and Alm revealed that grain spawn,and compost spawn,to which autoclaved
grains were added,all supported green mold colonies and drastically
decreased mushroom yield.These experiments were done with biotype Th4
of Trichoderma,whereas the experiments of Fletcher previously mentioned
using biotype Th2.The conclusion from the Rinker and Alm study is that
Trichoderma(biotype Th4)does not need cereal grain to initiate green
mold growth.These studies led to a further evaluation of the role of
spawn in green mold disease in which Trichoderma biotype Th4 was used
to infect the spawns.The spawn was kept under refrigeration for up to
12 months before use.In some experiments the spawn was used before
spawning.The results of this experimentation were that neither the
lenght of storage nor the warm up period prior to use produced
differences in number of colonies of green mold or their size.Thus,
these treatments had no tangible effect on the incidence or severity of
Trichoderma green mold disease.Next tested were the type of grain
(rye or millet)used to make the Agaricus spawn and the amount of spawn
used.The results here were the there was no difference in expression of
the diease between rye spawn and millet spawn,and an increase in the
amount of spawn up to twice the rate also had no effect on the
expression or severity of the disease.

Effect of Supplementation of Compost

Gandy reported that,when the composition of the mushroom compost was
amended after Phase 2 by the addition of sugars,the compost was rapidly
colonized by Trichoderma.In the British Isles it is biotype Th2 of
Trichoderma harzianum thats been responsible for the great crop losses,
whereas in North America biotype Th4 is responsible for losses in yield
incurred by the mushroom growers.Consequently,Rinker and Alm used
biotype Th4 in their studies on the effect of supplementation of the
compost on Trichoderma infection on commercial mushroom farms.It was
known that supplements added to the compost at spawning or casing can
increase mushroom yield up to 25%,but it was also known that these
supplements can serve as a food source for competitor molds such as
Trichoderma.In their studies Rinker and Alm amended the compost with
various commercial supplements either at spawning or before casing and
then inoculated the compost with a spore suspension of 1 to 2 billion
spores of biotype Th4.The spore suspension was pipetted into the bottom
of a 5-cm-deep hole beneath the compost surface in the center of each
tray.Supplements,applied either at spawning or casing,increased the
mushroom nonproductive area due to the growth of green mold.It was
observed that inoculation with biotype Th4 at the time of casing was
less damaging to the crop than inoculation at spawning.A particular
commercial supplement,Campbell's S-41,produced smaller green mold
colonies than either nonsupplemented compost or the other composts
amended with four different commercial supplements.The compost
supplemented with S-41 had increased mushroom yield,but S-41 contained
the mold-inhibitory compound thiabendazole.With the further addition of
benomyl to S-41,there was an additional reduction of diease symptoms
on the compost.With supplementation by S-41 and also the commercial
supplement called Feather Meal,the total mushroom yield was
significantly greater than the nonsupplemented biotype Th4-infested
control.Rinker and Alm state that care must be taken in the choice of
supplement and the timing of supplementation.These factors will be
dependent on the overall infection pressure on the specific mushroom
farm.Although increased yield can be derived from a supplement,this
increase can be negated by an expanded size of nonproductive areas
resulting from green mold.

Molecular Technologies

Molecular technologies have been very important in obtaining
knowledge about green mold diease.In particular,they have been used to
distinguish aggressive from nonaggressive forms of Trichoderma that are
morphologically similar,as well as to determine the prevailing type of
green mold on commercial mushroom farms.A clinical test for the rapid
determination of the aggressive biotype of Trichoderma(Th2 in Europe
and Th4 in North America)has resulted from these molecular studies.
Analysis by restriction fragment length polymorphism(RFLP)has
been successfully used to separate various isolated strains into groups
.In one study,81 isolates of Trichoderma from compost were studied by
RFLP analysis of ribosomal DNA and mitochondrial DNA.These isolates
could be placed in three major groups.An additional molecular technique
called random amplified polymorphic DNA analysis (RAPD)confirmed this
grouping.Because morphological characterisics can vary greatly from one
isolate to another,and because these traits are subject to
environmentally induced changes,the identification of Trichoderma
species and their relationships are now studies by molecular techniques
and computerized analysis.For example,with green mold occurring on
different continents,it would be useful to know the relationships of
various types that have been isolated as well as the origin of the
biotype.For such phylogenetic studies the molecular analysis of
specimens in which specific regions of threir DNA are analyzed by RFLP
or RAPD methods.The degree of similarity of DNA sequences of the
strains correlates with their relatedness.Organisms that are distantly
related have similarity only in regions of DNA that cannot change
without having a deleterious or at least significant impact in function
.Closely related organisms show differences in regions where
variability does not produce major effects.The result in the study of
green mold-causing isolates,when the sequences of six isolates were
compared with other sequences from data banks,indicated that there
were two distinct groups:

-Group 1 contained biotype Th1 and the aggressive biotypes
Th2(European)and Th4(North America)

-Group 2 contained biotype Th3

The phylogenetic tree obtained by using the molecular data indicated
that Th1 is the most recent ancestor for the aggressive types Th2 and
Th4.An extensive research project on the cause,edaphic factors,and
control of mushroom green mold has been carried out at Pennsylvania
State University and sponsored by the Pennsylvania Department of
Agriculture,using the facilities of the Penn State University Mushroom
Research Center.The results of the research were presented in a series
of reports.Some of the important contributions of these studies are as
follows:

-Demonstration that biotype Th4 of Trichoderma harzianum was the cause
of green mold disease on Pennsylvania mushroom farms

-Development of a clinical test involving DNA genetic fingerprinting
techniques for the rapid detection of biotype Th4,thus permitting
early detection and control of the disease

-Evidence that a recent introduction of Th4 into mushrooms under
cultivation was responsible for the green mold epidemic in
Pennsylvania

-Demonstration that deployment of biocontrol Trichoderma on
crop plants was not responsible for green mold epidemics

-Demonstration that the effectiveness of benomyl-treated spawn in
control of Th4 biotype green mold disease

-Determination that the use of grain spawn exacerbates green mold
disease,as does nitrogen supplementation at spawning and high casing
moisture

-Demonstration that the severity of green mold was increased under
low oxygen conditions during Phase 2 composting and that biotype Th4
cannot survive a properly managed Phase 2 pasteurization

-Demonstration that it is not possible to manipulate the temperature
at the time of spawn run to give a selective advantage to the growth
of mushroom mycelium over the Trichoderma green mold

-Demonstration that there was greater loss by the green mold fungus
with infestation of the compost at spawning than with introduction
of Trichoderma at casing

-Demonstration of a 24C registration for the use of Terraclo as a
sanitizing agent for Trichoderma on wood surfaces and floors

-Demonstration that other compost molds can alter the expression of
Trichoderma green mold disease

Methods of Control

Information on the control of green mold has been given previously,
but now we direct our attention to the results of some studies in which
control was the primary concern.The first study to be examined is that
of Grogan et al.,which used biotype Th2,the most aggressive strain of
Trichoderma in the United Kingdom.Th2 is responsible for serious
reductions in the yield of A.bisporus.The study made a number of
observations that are worthy of mention,even though some of these have
been presented previously in reports of green mold disease in
North America where biotype Th4 is the strain responsible for the
epidemics.Some of their observations and experimental results include
the following:

-Th2 colonizes the mushroom compost during spawn run and prevents
the mycelium from becoming established

-In the absence of cereal grains the green mold did not become
established in the compost

-Once the green mold has become apparent,its too late to prevent
substantial yield losses

-All plots that had received spawn inoculated with biotype Th2
experienced a reduction in yield due to compost green mold

Additional studies have been made on the use of fungicides to control
green mold.In some cases,the spawn was treated with the fungicide;in
other cases the compost was treated.Grogan et al.used the fungicides
carbendazim,thiabendazole,and benomyl.When the fungicide was used on
spawn,carbendazim gave the best results.With carbendazim the mushroom
yield was 84% compared with 100% for uninoculated
(no Trichoderma biotype Th2) compost and 38% for uninoculated compost
with no fungicide treatment.The mushroom yield with thiabendazole
treatment was 77% and with benomyl 58%.When the fungicide was applied
to the compost,the mushroom yields compared to the control were 69%
with benomyl,71% with carbendazim,and 44% with thiabendazole.In these
experiments,none of the treatments with fungicide had significat
phytotoxic effects on mushroom yield.
From these studies,generalizations can be drawn as follows:

1-Hygiene on the mushroom farm is extremely important for it was
found that with poor hygiene conditions a small green mold outbreak
can rapidly escalate out of control

2-Treatment of spawn with fungicide was more effective than treatment
of compost.The evidence for this was that only 1.15g of fungicide
per ton of compost was required when the fungicide was applied to
the spawn,whereas 70g of fungicide per ton of compost was required
when the compost was treated

3-From the standpoint of government regulation of fungicides,these
studies showed that the fungicide residues in mushrooms harvested
from fungicide treated crops were less than the maximum residue
level permitted in the United Kingdom for carbendazim in fungi

In the United States,approval from the Pennsylvania State Department
of Agriculture has been given for the use of Benlate(benomyl)on spawn
to control Trichoderma green mold.The approval label allows for Benlate
to be mixed with a carrier such as gypsum,limestone,or chalk,and this
mixture is then used to coat the spawn grains prior to their use in
spawning compost.
An important generalization about control of Trichoderma green mold
is that if the spawn grain is protected with fungicide,thus preventing
colonization of the compost by Trichoderma green mold,the mushroom
mycelium will grow vigorously from the spawn grain into the compost.
Unfortunately,there may be an adverse side effect in that both
Verticillium and Dactylium have shown resistance to benzimidazole
fungicides,and thus these weed fungi may become a problem.Care in the
use of fungicides and hygiene practices in the mushroom houses are
absolutely essential.

by Shu-Ting Chang Ph.D

[dfar]

thanks for sharing... some useful info there

[zep101]

here's a sweet thread from the archives that will help for proper use of fungicides and such. doesn't touch on quite the same chems used in the report I posted above but has names of products that you can actually find and tried tested and true methods of use. my sub that I have now (sheeppoo/verm/coir) that was properly pasterized has no trich(cross fingers) but the seeds, no matter what, seem to get it with no fungicide of course.
anyhoo here's the link
http://archives.mycotopia.net/discus...s/5/32196.html
Thanks to rodger rabbit and hippie3 and soliver for asking the question in the first place. I will order the banrot 40wp and see how it goes

[hyphaenation]

I found this to be an interesting read on Trichoderma:

Trichoderma spp. is the cause of green mold, a disorder that affects cultivated mushrooms. The aims of the study were to establish whether improvement of mushroom resistance to Trichoderma aggressivum could be obtained by inducing reaction mechanisms before contact with the pathogen and whether this ability was species or strain dependent. Twenty nine isolates of Agaricus bisporus, 29 isolates of Lentinula edodes and 18 isolates of Pleurotus spp. were studied. The effect of T. harzianum metabolites on mycelial growth of these isolates was evaluated on YMEA (yeast, malt extract and agar), supplemented or not with Lysing Enzymes from T. harzianum (Sigma®, L1412). Mycelial growth generally was affected by Lysing Enzymes, but some L. edodes and Pleurotus spp. adapted to Lysing Enzymes.

When mycelium was taken from a first culture with Lysing Enzymes and placed on YMEA with Lysing Enzymes for a second culture, their growth rate was not different from those of the controls. In the case of A. bisporus, only partial adaptation was obtained with a few isolates. The effect of adaptation to Lysing Enzymes on resistance to T. aggressivum was assayed for one strain of each group. Trichoderma aggressivum was exposed to the margin of 5- to 9-day-old mushroom colonies.

Agaricus bisporus produced brown droplets, and T. aggressivum overgrew its mycelium. Lentinula edodes and P. ostreatus produced brown lines blocking the progression of T. harzianum, both on YMEA and YMEA plus Lysing Enzymes. The line was visible after 3 d on YMEA and after only 2 d on YMEA plus Lysing Enzymes. Improvement in the resistance to antagonists by introduction of some of their metabolites to the culture medium is a method for mushroom protection.

Further reading:
http://www.mycologia.org/cgi/content/full/95/2/191

[hyphaenation]

Another angle on Trichoderma.

http://www.nysaes.cornell.edu/ent/bi...ichoderma.html

[zep101]

wow that's such a plethora of information! I've been able to get a tray laid out (sheepshit/coir/verm) could I mix it up prior to fruiting and lay that into an even larger tray and keep it in the dark to continue eating the sub? or would that disturb it too much and kill it? the trich don't grow on my PH2 pasteurized sub pretty sure the trich is within the local ecosystem around this house.
I even tried to order banrot 40wp and after all the billing, shipping, and brokerage fees. I was told that they do not ship to my location. but ya I could possibly expand by using my sub essentially as a spawn