The Value of Trichoderma for Crop Production

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What is Trichoderma?
Trichoderma is a genus of fungi
commonly found in soil ecosystems
worldwide. The fungus grows along
root surfaces and just below the
outermost cells (or “skin”) of roots.
Trichoderma feed on soil microbes
that are attracted to the root system
and surrounding soil (rhizosphere) by
root-excreted sugars. High microbial
populations near the root system
encourage Trichoderma to grow within
root intercellular spaces and close
to plant root surfaces, coordinating
defenses against plant diseases and
insects and increasing plant vigor.
While most species of this genus are
beneficial to plant health, a recent
finding has identified one species (T.
viride) that is pathogenic on Austrian
pine.1
What is the dierence
between native and
commercial Trichoderma
species?
Native Trichoderma are present in soils
worldwide. Commercial Trichoderma
species are those from the natural
community selected for their ability
to outcompete other soil organisms
and colonize plant root systems more
aggressively.
How can Trichoderma help
my crops?
Decades of research shows that
several commercialized Trichoderma
inoculant strains can increase plant
growth potential, disease resistance,
and resistance to environmental
stresses.3 In many cases, plant
pathogen resistance is improved in
plants regardless of environmental
stresses. However, increased plant
growth potential is only documented
when plants are under stress conditions
(e.g., low nutrients, high salinity, heat,
saturated soil). Plants under non-stress
conditions do not show increased
growth.
Plant disease management
Specific Trichoderma species may:
• Outcompete fungal and fungal-
like plant pathogens for nutrient
and space resources on plant roots,
resulting in reduced pathogen
success and plant disease.
• Recognize and attack harmful fungal
and fungal-like plant pathogens
by dissolving their cell walls and
absorbing the released nutrients (a
process called mycoparasitism).
• Promote general plant disease
defenses, increasing the “immunity”
(acquired resistance) of the plant.
The value of Trichoderma
for crop production
Georey Siemering, Matthew Ruark,
and Amanda Gevens
A4114-02
BIOLOGY
SOIL
Key facts
• Trichoderma are fungi that grow
in and around plant roots and
associate with all plant types.
• Research indicates Trichoderma
inoculants can help plants
overcome environmental stresses
to reach their yield potential, but
are unlikely to increase yields under
non-stress conditions.
• Trichoderma can minimize disease
damage from several root rot
fungi and fungal-like microbes
including Botrytis, Fusarium,
Pythium, and Rhizoctonia.
• Most published Trichoderma
research comes from greenhouse
rather than field studies.
• No soil test is available to
determine if Trichoderma
application is recommended.
• We are currently unable to predict
if Trichoderma inoculants will be
economically beneficial.

THE VALUE OF TRICHODERMA FOR CROP PRODUCTION
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• Research indicates several species
of Trichoderma may protect plants
from attack by root-knot and cyst
nematodes. The fungus can colonize
nematode eggs and second stage
juveniles,4 as well as certain parts
of adult nematodes,5 utilizing the
nematodes as a food source.
Relief from environmental
stresses
Trichoderma colonization can help
plants overcome environmental
stresses through increased root
growth and photosynthesis.
Specifically, Trichoderma colonization
can:
• Increase seedling vigor and
germination.6
• Act as a plant antioxidant, increasing
photosynthesis efficiency in stressed
plants.7
• Increase plant hormone production,
thereby increasing root growth and
root hair formation. This augmented
plant root architecture results in
more efficient use of nitrogen,
phosphorus, potassium, and
micronutrients.8
Increased crop yield
Research has shown that Trichoderma
colonization of crops can lead to
increased yield under stress conditions.
• Colonization of corn induced higher
photosynthetic rates and systemic
increases in CO2 uptake in leaves.9
• Colonized corn grown under
drought conditions had increased
harvest biomass compared to non-
inoculated corn.10
• Radish, potato, pepper, cucumber,
tomato, pea, and canola crops
experienced increased growth
associated with Trichoderma
colonization.11
• Sweet corn and soybeans treated
with Trichoderma and planted
under suboptimal conditions
(early planting, moderate nitrogen
fertilizer, and low plant population)
had increased yields of 20% and
10%, respectively, over untreated
plants.12
• Trichoderma inoculation of a cover
crop increased subsequent potato
yields up to 37% under low nutrient
conditions.13
• While shown beneficial in
greenhouse experiments, more
research is required to assess
field-scale yield gains related to
Trichoderma inoculant use.
FIGURE 1: How Trichoderma can impact plant health
N
P
K
Increases secondary root
development to boost
nutrient uptake
Attacks nematode eggs
and second-stage juv
eniles
Increases plant disease defenses
Recognizes and attacks
harmful plant pathogens
Increases crop yield
under stress conditions
Trichoderma
pathogen fungus
Trichoderma
nematode
protective
gel layer
plant root
pathogen fungus

UNIVERSITY OF WISCONSIN-EXTENSION
3
Fungicide use
As Trichoderma are typically applied
at seeding and are intended to
establish the fungus in and on plant
roots, foliar fungicide applications will
unlikely affect colonization. Fungicides
coapplied at seeding will greatly
reduce Trichoderma effectiveness.
Will my crop management
practices impact
Trichoderma growth?
Crop management practices have
little impact on Trichoderma. Unlike
arbuscular mycorrhizal fungi (AMF),
Trichoderma structures do not retain
effectiveness season-to-season.
• Trichoderma colonize plants and
grow best under conditions also
favorable to plant growth (moderate
temperatures and moisture content).
• Tillage practices appear to have no
impact on Trichoderma colonization.
• Trichoderma are not crop specific
and will colonize all crop plants
regardless of rotation.
• Seed application is more effective
than midseason application in
providing plant benefits.
Can I use Trichoderma and
AMF inoculants at the
same time?
Scientific data is inconclusive about
how AMF and Trichoderma interact,
but studies support the use of both
simultaneously.14 One study found
the co-inoculation of cover crops
increased the next season’s potato
yields up to 37%.15 Trichoderma
and AMF naturally coexist in the
rhizosphere. However, inoculants
may temporarily upset the balance
between the two.
Should I inoculate my
crops with Trichoderma?
It is important to remember that if
there are no environmental stresses to
overcome, benefits from inoculation
will be limited. For example, a
single-year study on soybean in
Wisconsin found no yield increase
with Trichoderma inoculation, but
soybean yields in this study averaged
80 bushels per acre, approximately
30 bushels more than the 10-year
average.16
One or more Trichoderma species
are used in commercially available
inoculants, including Trichoderma
harzianum, Trichoderma virens, and
Trichoderma viride. Many of their
impacts on crops are similar, but
there are species-specific and even
strain-specific interactions. Inoculants
containing different species or strains
may perform differently under similar
field and weather conditions.
Research indicates Trichoderma
inoculation could potentially benefit
plant health in crops such as corn,
potato, soybean, alfalfa, wheat,
ornamentals, and other vegetables.
Variable effects of Trichoderma
inoculation on disease prevalence
have been documented with trials
showing either positive, negative or
no impact.17 It is important to note
that biocontrol product studies,
particularly those showing no yield
increase, are frequently not published,
thereby leading to positive-effect
bias in a limited peer-reviewed body
of literature. Commercial use of
Trichoderma inoculants in field and
vegetable crops is limited, with more
extensive adoption in greenhouse-
grown ornamentals. Limited adoption
of Trichoderma in field crops may be
the result of multiple factors including
cost, relative efficacy compared to
conventional pesticides, and lack of
research on specific crops.
Further reading
O’Callaghan, M. “Microbial inoculation of
seed for improved crop performance:
issues and opportunities.” Applied
Microbiology and Biotechnology(2016):
1–18. http://link.springer.com/
article/10.1007/s00253-016-7590-9
Iowa State University, Agronomy Extension.
“Compendium of Research Reports on
Use of Non-Traditional Materials for Crop
Production.” http://extension.agron.
iastate.edu/compendium/index.aspx
References
1 Destri Nicosia, M. G., et al. “Dieback of
Pinus nigra seedlings caused by a strain
of Trichoderma viride.” Plant Disease 99.1
(2015): 44–49.
2 Druzhinina, I. S., et al. “Trichoderma:
the genomics of opportunistic
success.”Nature Reviews
Microbiology9.10 (2011): 749–759.
3 Hermosa, R., et al. “Plant-benecial
eects of Trichoderma and of its genes.”
Microbiology158.1 (2012): 17–25.
4 Casas-Flores, S. E. and Herrera-Estrella,
A. “The mycota: a comprehensive
treatise on fungi as experimental
systems for basic and applied
research.” Environmental and Microbial
Relationships 4 (2007): 159–187.
5 Sharon, E. M., et al. “Biological control of
the root-knot nematode Meloidogyne
javanica by Trichoderma harzianum.”
Phytopathology91.7 (2001): 687–693.
Suarez, B., et al. “Isolation and
characterization of PRA1, a trypsin-like
protease from the biocontrol agent
Trichoderma harzianum CECT 2413
displaying nematicidal activity.” Applied
Microbiology and Biotechnology 65
(2004): 46–55.
Chen, L., et al. “Characterization and gene
cloning of a novel serine protease with
nematicidal activity from Trichoderma
pseudokoningii SMF2.” FEMS Microbiology
Letters 299.2 (2009): 135–142.
6 Mastouri, F., et al. “Seed treatment
with Trichoderma harzianum alleviates
biotic, abiotic, and physiological
stresses in germinating seeds and
seedlings.”Phytopathology 100.11 (2010):
1213–1221.
7 Ibid.

THE VALUE OF TRICHODERMA FOR CROP PRODUCTION
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8 Samolski, I., et al. “The qid74 gene
from Trichoderma harzianum has a
role in root architecture and plant
biofertilization.”Microbiology158.1
(2012): 129–138.
9 Vargas, W. A., et al. “Plant-derived
sucrose is a key element in the symbiotic
association between Trichoderma virens
and maize plants.”Plant Physiology151.2
(2009): 792–808.
10 Guler, N. S., et al. “Trichoderma atroviride
ID20G inoculation ameliorates
drought stress-induced damages by
improving antioxidant defence in
maize seedlings.”Acta Physiologiae
Plantarum38.6 (2016): 1–9.
11 Altomare, C., et al. “Solubilization of
phosphates and micronutrients by the
plant-growth-promoting and biocontrol
fungus Trichoderma harzianum Rifai
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Tucci, M., et al. “The beneficial effect of
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Viterbo, A., et al. (2010). Characterization
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Vinale, F., et al. “A novel role
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Harman, Gary E. “Myths and dogmas
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12 Björkman, T., et al. “Growth enhancement
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John, R. P., et al. “Mycoparasitic
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13 Buysens, C., et al. “Inoculation of
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Rhizophagus irregularis and Trichoderma
harzianum increases the yield of
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low nutrient conditions.”Applied Soil
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14 Green, H., et al. “Suppression of
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Vassilev, N.M., et al. “Unexploited
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15 Buysens, C., et al. “Inoculation of
Medicago sativa cover crop with
Rhizophagus irregularis and Trichoderma
harzianum increases the yield of
subsequently-grown potato under
low nutrient conditions.”Applied Soil
Ecology105 (2016): 137–143.
16 Shawn Conley (associate professor,
College of Agricultural and Life Sciences,
UW–Madison), personal communication,
June 15, 2016.
17 Zitter, T., et al. 2007. “Biofungicides and
sustainable products compared with
conventional fungicides for potato
production, 2006.” Plant Disease
Management Reports. Report 1: V064.
The American Phytopathological Society.
DOI: 10.1094/PDMR01.
Funahashi, F. and Parke, J. L. 2016.
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© 2016 University of Wisconsin System Board of Regents and University of Wisconsin-Extension, Cooperative Extension. All rights
reserved.
Authors: Department of Soil Science: Geoffrey Siemering, outreach specialist; Matthew Ruark, associate professor. Department of Plant
Pathology: Amanda Gevens, associate professor. All with UW–Madison and UW-Extension. Cooperative Extension publications are
subject to peer review.
University of Wisconsin-Extension, Cooperative Extension, in cooperation with the U.S. Department of Agriculture and Wisconsin
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The Value of Trichoderma for Crop Production (A4114-02) I-11-2016