1. BIOLOGICAL CONTROL FOR PLANT
DISEASE MANAGEMENT:
Understanding the options and
their effectiveness
Rodale Institute

2. Introduction
Cornell University Department of Plant Pathology
• Botrytis cineria inoculation techniques in onion
• 1st detection of Pantoea ananatis and completion of Koch’s
Postulates in onion
• Drs. Jim Lorbeer and Steve Beer

3. Introduction
Cornell University Department of Plant Pathology
• Vermicompost-mediated disease suppression of Pythium
aphanidermatum
• Dr. Eric Nelson

4. Introduction
Campos Laguna Blanca and Malambo, Argentina
• Compost, vermicompost and compost extract production,
management, application and evaluation
Windrow compost
Application and evaluationLiquid vermicompost
extracts
Vermicompost
Teas/extracts

6. Introduction
Rodale Institute, Kutztown, PA
• Compost Production Specialist
• Organic Allentown - Vertical gardening and marketing for urban
agriculture
• Master Composters of Rodale Institute
• Novel seed treatment techniques for plant disease management

9. Outline
• Introduction
• Presentation goals and disclaimer
• Defining plant pests and diseases
• Disease triangle
• The infected plant – an overview of pests and diseases
• Biological control products and their effectiveness
• Conclusions and disclaimers revisited

10. Presentation goals and disclaimer
Goals
• Terminology
• Overview of plant pathology
• Products and active ingredients
• Some application do’s and don’ts
• What tools to add to the disease management toolbox
Disclaimer
• Not supporting one product, manufacturer, approach,
technique, over another.
• Only intend to deliver valid information so that you
may make educated decisions regarding your pest and
disease management strategy.

11. Defining plant pests and diseases
What is a plant disease?
Agrios, 1988. Plant Pathology.
“Any malfunctioning of host cells and tissues that results
from continuous irritation by a pathogenic agent or
environmental factors and leads to development of
symptoms.”
Carr et al., 2012.
“A human interpretation of a plant physiological disorder.”

12. Defining plant pests and diseases
What is a plant disease?
Examples:
Powdery mildew of cucurbits (Podosphaera xanthii)

13. Defining plant pests and diseases
What is a plant disease?
Examples:
Cucumber Mosaic Virus (CMV)

14. Defining plant pests and diseases
What is a plant disease? Plant pest?
Examples:
Symptoms due to aphids
https://extension.umass.edu

15. Defining plant pests and diseases
What is a plant disease?
Examples:
Yellowing due to nutrient deficiency
Heat stress
Air pollution
Soil compaction
Understanding the causal agent (biotic/abiotic) is the first
step towards disease management.

16. Disease triangle
Pathogen, host and environment
One of the three can be altered to prevent disease.
• Pathogen – alter behavior
• Host – resistant varieties
• Environment – modify temperature or moisture
Agrios, 1988

17. The infected cell – overview of pests and diseases
Agrios, 1988

18. The infected cell – overview of pests and diseases
Agrios 2005

19. The infected cell – overview of pests and diseases
Generalist vs. specialist (Pythium vs. Phytophthora)

20. The infected cell – overview of pests and diseases
Multiple developmental stages with some requiring specific
environmental conditions.
• Pythium zoospore production requires flooded conditions
• Phytophthora zoospore production requires high humidity and 53-
59°F
Agrios, 1988

21. Indirect germination in
sterile water
Duration = 45 min, 2 min intervals
Duration = 20 min, 10 sec intervals

22. Direct germination in
vermicompost extract

23. The infected cell – overview of pests and diseases
Understanding the pathogen/pest and its biology will help
develop effective disease management strategies.

24. Biological control products and their effectiveness
Presentation of information:
• Product/material name
• Active ingredient
• Uses (pests, diseases, foliar, soil-borne)
• Mechanism(s) of suppression
• Evaluation (research and anecdotal)

25. Product:
Active ingredient:
Uses:
Mechanism(s) of suppression:
Evaluation:
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

26. Meta-analysis to determine the overall effectiveness of
biocontrol in relation to biological and application-
oriented factors; 149 entries from 53 reports.
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

27. EFFECTIVE
BIOLOGICAL CONTROL
Aerial vs. soil-borne
disease
Greenhouse vs. field
Disease pressure
Number of applications
Pathogen type
Annual vs. perennial
Biocontrol agent
Fungal vs. bacterial
Environmental
conditions
Temperature
Moisture

28. • Disease pressure
• No significant difference in efficacy
• Aerial vs. soil-borne diseases
• No significant difference in efficacy
• For aerial diseases, 1 or 2 sprays more effective
than those that received 8 or more sprays
• Annual vs. perennial crops
• Disease suppression greater with annual crops
• Greenhouse vs. field
• No significant difference in efficacy
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

29. • Fungal vs. bacterial biocontrol agents
• No significant difference in efficacy
• r-selected biocontrol agents (i.e. those having
short generation times and producing large
numbers of short-lived offspring) more
effective
• Bacillus spp. less effective than other
antagonists
• Fungal vs. bacterial pathogens
• No significant difference in efficacy
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

30. OVERALL
• Variability in success – inherent in biological control
• Several other reports would challenge these results
• Difficult to synthesize data due to differences in
methodologies, environmental conditions and
plant-pathogen interactions
Understanding the options and their effectiveness is
key to pest and disease management.
Information pulled from published reports and
practitioner interviews.
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

31. Product: RootShield®, Trichodex, Binab-T Biological
Fungicides (and several others)
Active ingredient: Trichoderma spp. including T.
harzianum, T22
Uses: Soil amendment, seed treatment, dust or spray;
protects roots from several pathogens including
Pythium, Rhizoctonia, Fusarium, Thielaviopsis and
Cylindrocladium
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

32. Product: RootShield®, Trichodex, Binab-T Biological
Fungicides (and several others)
Active ingredient: Trichoderma spp.
Mechanism(s) of suppression:
• Mycoparasitism via production of chitinases
and β 1-3 and β 1-4 glucanases
• Antibiotics
• Competition
• Induced resistance
• Solubilization of inorganic plant nutrients
• Inactivation of pathogen enzyme production
Paulitz & Bélanger 2001
Schuster & Schmoll 2010
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal
biocontrol.entomology.cornell.edu

33. Product: Trichoderma harzianum, T22
Evaluation:
• Works very well but costly*
• Used in all greenhouse potting media*
• Six-month shelf life*
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal Martínez-Mendina et al. 2013
Inoculated with Botrytis cinerea

34. Product: Trichoderma harzianum, T22
Evaluation:
• Effective control for a variety of plant disease
(Verma et al. 2007)
• Extended dry conditions will affect success
(Esposito & da Silva 1998)
• Control is similar to synthetic fungicides
(Paulitz & Bélanger 2001)
• Most Trichoderma spp. based biocontrol
agents are unregistered and marketed as “soil
enhancers” (Verma et al. 2007)
• Increased commercialization is hindered by
defining the mode of action and
underdeveloped bioassay methods (Verma et
al. 2007)
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

35. Product: Bt (Bacillus thuringiensis) Insecticides
Active ingredient: Bt toxins (Cry ad Cyt toxins)
Uses: dusted or sprayed; control lepidoptera insects
(cabbage worm, caterpiller, cabbage looper, etc.)
Numerous commercial formulations and products exist
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

36. Product: Bt (Bacillus thuringiensis) Insecticides
Mechanism(s) of suppression: pore forming toxins that
kill larval epithelium midgut cells causing an
osmotic shock leading to cell lysis
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal
mbio.asm.org

37. Product: Bt (Bacillus thuringiensis) Insecticides
Evaluation:
• Sprayed 1-2 weeks before harvest as a
preventative*
• Spray just the heads or parts to be harvested*
• Works and is cheap*
• Sometimes sprayed in the greenhouse in the
fall*
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

38. Product: Bt (Bacillus thuringiensis) Insecticides
Evaluation:
• Many Bt strains show activity towards several
insect groups (Schnepf et al. 1998; Sanahuja et
al. 2011)
• Insect resistance (Bravo et al. 2013) and non-
target species (Cory & Franklin 2012) are a
concern
• Other insect pathogens exist (Beauveria and
Metarhizium spp., baculovirus and
entomopathogenic nematodes) (Cory & Franklin
2012)
• Bt sprays persist for only a few days on the leaf
surface because several factors contribute to
the degradation of Cry protiens, therefore re-
application necessary for full effect (Sanahuja et
al. 2011)
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

39. Product: Plant Growth-Promoting Rhizobacteria
(PGPR), Serenade Optimum
Active ingredient: Bacillus spp., Curtobacterium
flaccumfaciens, Burkholderia cepacia,
Enterobacter cloacae, Erwinia herbicola,
Psuedomonas spp. and others
Uses: dusted or sprayed; broad spectrum fungicide
and bactericide; late season diseases from
Botrytis, Sclerotinia, Xanthomonas, Erwinia; grape,
strawberries, leafy vegetables, potatoes, pome
fruit, tree nuts and others
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal
aps.net

40. Product: Plant Growth-Promoting Rhizobacteria
Mechanism(s) of suppression: secretion of bioactive
molecules such as antibiotics and cell-wall
degrading enzymes (De Curtis et al. 2010);
nutrient competition (Nelson 2004)
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal
Scialert.net gopixpic.com

41. Product: Plant Growth-Promoting Rhizobacteria
Evaluation:
• Not all products registered as biocontrol
agents – marked as plant growth promoters,
strengtheners, or soil conditioners (Paulitz &
Bélanger 2001)
• Bacillus subtilis exhibited variable suppression
of Rhizoctonia solani and Sclerotium rolfsii on
tomato (De Curtis et al. 2010)
• Strain mixtures more effective than single
strains (Raupach & Klopper 1988)
• Enterobacter spp., Psuedomonas spp. and
Bacillus spp. digested seed exudates to make
the host plant undetectable to Pythium -
carbon competition suggested to be the
leading mechanisms of suppression (Nelson
2004; Chen et al. 2012)
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

42. Product: Biocontrol yeasts (Botector®)
Active ingredient: Rhodotorula glutinis, Cryptococcus
laurentii, Aureobasidium pullulans
Uses: Field and post-harvest diseases from pathogens
such as Botrytis cinerea, and Penicillium
expansum, Rhizopus stolonifer, Aspergillus niger;
grape, apple, cherry tomato, cherry and others
Mechanism(s) of suppression: antibiosis due to
pullulans, extracellular enzymes, siderophores and
single-cell proteins (Chi et al. 2009); competition
for nutrients (Chi et al. 2009)
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal
plantmanagementnetwork.org endure-network.eu postharvest.ucdavis.edu

43. Product: Biocontrol yeasts
Evaluation:
• Consistent high reductions in fungal decay
(Lima et al. 2003; Chi et al. 2009)
• Cause less phytotoxicity compared to copper
hydroxide and lime sulphur but were not as
effective at reducing blossom blight in cherry
production (Holb & Kunz 2013)
• Yeast cell concentration significantly
correlated to efficacy (Mari et al. 2012)
• New trials will be conducted at three separate
apple orchard locations to control Bitter Rot
of apple (Glomerella cingulata) (Rodale
Institute, 2015)
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

44. Product: Bordeaux mixture and other copper and
sulfur-based treatments
Active ingredient: Copper and sulfur
Uses: General biocide for fungal and bacterial
pathogens
Mechanism(s) of suppression: copper compounds
react with fungal spore exudates to create highly
toxic copper complexes; high pH in lime sulfur
disrupts fungal spore membrane activity (Montag
et al. 2005 & 2006)
Evaluation:
• Works but not preferred due to non-target
effects*
• Phytotoxic effects at large doses*
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

45. Product: Bordeaux mixture and other copper and
sulfur-based treatments
Evaluation:
• Long history of success and effectiveness
(Agrios 1988; Hamilton & Keitt 1928)
• Effective during the infection process (Jamar
et al. 2008)
• Effects on non-target and beneficials are a
concern (Bengochea et al. 2014; Wang et al. 2009)
• Can accumulate is plant parts (Iwane 2009;
Kurnik et al. 2012; Liu et al. 2011)
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

46. Product: Bordeaux mixture and other copper and
sulfur-based treatments
Evaluation:
• Can be phytotoxic (Yoder et al. 2009; Holb et
al. 2003)
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal
rhizotest.cirad.fr msue.anr.msu.edu

47. Product: Surround® WP
Active ingredient: Kaolin clay
Uses: Crop protectant for controlling damage from
various insect and disease pests
Mechanism(s) of suppression: forms a barrier film,
which acts as a broad spectrum crop protectant
Evaluation:
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal
www.planetnatural.com www.goodfruit.com

48. Product: Surround® WP
Active ingredient: Kaolin clay
Uses: Crop protectant for controlling damage from
various insect and disease pests
Mechanism(s) of suppression: forms a barrier film,
which acts as a broad spectrum crop protectant
Evaluation:
• Sprayed on cucurbits for cucumber beetles*
• Acts as a “spray-on row cover”*
• Confident that it improves apple production*
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

49. Product: Surround® WP
Evaluation:
• Whitish appearance on fruit can significantly
reduce consumer acceptance and fruit value
(Peck et al. 2010; Wismer 2009)
• Must be used in large quantities to be
efficacious (Reissig et al. 2002)
• Although it is an inert compound, it can
potentially cause respiratory, dermal and eye
irritations (Peck et al. 2010)
• Effects on non-target and natural enemies are
a concern (Bengochae et al. 2010 & 2013;
Scalercio et al. 2010)
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal
www.goodfruit.com

50. Product: JMS Stylet-Oil®
Active ingredient: Paraffinic oil
Uses: for controlling fungal diseases, aphid-
transmitted plant viruses, insects and mites
Mechanism(s) of suppression: cell wall disruption
Evaluation:
• Sprayed on cucurbits for downy and powdery
mildews*
• Often sprayed as a preventative*
• Cheap and works*
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

51. Product: JMS Stylet-Oil®
Evaluation:
• Applying every 4 days was more effective
than a single application (McGrath &
Shishkoff 2000)
• Less effective at suppressing foliar diseases
when applied after detection (McGrath 2009)
• Effective at controlling virus vectors such as
aphids (McDonald et al. 2004)
• Effectiveness directly related to spray
coverage (JMS Stylet-Oil website)
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal
ontargetspray.com

52. Product: Neem Oil (Azadirachta indica)
Active ingredient: azadirachtin
Uses: broad spectrum insecticide/miticide; fungal
preventative
Mechanism(s) of suppression: when ingested, prevents
molting and suppresses feeding; suffocates insects
and mites on contact
Evaluation:
• Used for harlequin cabbage bug*
• Used outside on brassicas*
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal
article.wn.com indiamart.com

53. Product: Neem Oil
Evaluation:
• Effects non-target species such as bees
(product lable); used as a last resort*
• Synergy was not expressed when mixing
neem oil with Bt and/or Beauveria bassiana
(Togbe et al. 2014)
• Success not always realized (Ahmady & Kumar
2014); Bt more effective (Padhi et al. 2013)
• “Most environmentally friendly pesticide,
highly biodigradable and leaves no residues
on food stuff.” (Mathur 2013)
• Variable results
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

54. Product: PyGanic®
Active ingredient: Pyrethrin
Uses: Broad spectrum insecticide
Mechanism(s) of suppression: Sodium channel
modulator – disrupts insects’ nervous system
Evaluation:
• Kills all it hits*
• Used only inside*
• Used only when necessary*
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal njaes.rutgers.eduextension.umn.edu

55. Product: PyGanic®
Evaluation:
• Effects on non-target and beneficials is a
concern (Tunca et al. 2012)
• Variable results in controlling different aphid
species (Andreev et al. 2012)
• Variable results in controlling different stink
bug species (Lee et al. 2014)
• In most reports, control was >75% successful
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

56. Product: Thermogenic compost, vermicompost and
liquid compost/vermicompost teas and extracts
Active ingredient: Microorganisms and microbial
byproducts
Uses: Soil amendment for plant production and
protection against a wide range of pests and
pathogens
Mechanism(s) of suppression: antibiosis, nutrient
competition, predation, altering pathogen
development, systemic acquired resistance (SAR)
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

57. Product: Thermogenic compost, vermicompost and
liquid compost/vermicompost teas and extracts
Evaluation:
• Several benefits (Jack & Thies 2005; Hadar &
Papadopoulou 2012)
• Suppresses a wide range of pathogens (Noble
2011)
• More effective as a soil amendment than a
spray (Litterick et al. 2004; Scheuerell &
Mahaffee 2002)
• Variable and unpredictable (Scheuerell &
Mahaffee 2006; Noble & Coventry 2005)
• Organic matter and high biological diversity
appear to be the key components in regards
to biological control (Bonanomi et al. 2010;
Hoitink & Fahy 1986)
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

58. Product: Mulches, cover crops and crop rotation
Active ingredient: Planning and prevention
Uses: general crop protection and disease prevention
Mechanism(s) of suppression: Prevention, avoidance
and improving soil health
Evaluation:
• Crop rotation to disrupt disease and pest
cycles and avoid disease pressure (Agrios
1988)
• Mulches to feed soil microbes and disrupt
disease and pest cycles
• Cover crops increase organic matter and feed
microbes
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

59. Product: Mulches, cover crops and crop rotation
Active ingredient: Planning and prevention
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

60. Product: Plant Growth-Promoting Rhizobacteria,
Trichoderma
Active ingredient: Bacillus spp., Psuedomonas spp. and
others; compost extracts
Uses: Seed treatment to prevent fungal and bacterial,
soil-borne plant pathogens; pathogen disinfection
Mechanism(s) of suppression: Nutrient competition,
antibiosis, systemic acquired resistance, and
others
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal
wwf.panda.orgag.arizona.edu

61. Product: Plant Growth-Promoting Rhizobacteria
Evaluation:
• Little anecdotal information
• Multiple strain treatments were most
effective on cucumber in the field for plant
growth promotion and disease reduction
(Raupach & Kloepper 1988)
• Tomato seeds soaked in liquid cultures of
Bacillus spp. completely inhibited Clavibacter
michiganensis incidence (Kasselaki et al.
2011)
• Tomatos seeds soaked overnight in 3-day old
compost extracts completely inhibited
Clavibacter michiganensis incidence; the
compost used to prepare the extract did not
affect suppression (Kasselaki et al. 2011)
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

62. Notes on what was not mentioned….
• There are literally hundreds of biocontrol options
• Plant extracts and oils, bacteria from milk, viruses,
non-pathogenic fungi, numerous single-strain
biocontrol agents…
• Difficult to synthesize lab and field results due to
differences in methodologies
• Often unpredictable and variable
When considering a product or material…
• Typically the most effective treatments are those
with the rigorous of testing
• New commercial products vs. old products
• Manufacturer credibility
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

63. Product: Freeze-dried compost extracts
Active ingredient: microorganisms and microbial
byproducts
Uses: Preventing and suppressing soil-borne seed and
seedling pathogens
Mechanism(s) of suppression: nutrient competition,
antibiosis, predation
Evaluation:
• Applying microbes closer to the site of
infection
• Establishing a proof of concept
Commercial products
• Single-strain biocontrol agents
• Non-biologicals
Non-commercial products
• Multi-strain biocontrol agents
–Compost
–Vermicompost
–Teas and extracts
• Prevention practices
–Mulches
–Cover crops
–Crop rotation
Seed treatments
• Single-strain agents
–Psuedomonas
–Bacillus
–Trichoderma
• Novel treatments
*Anecdotal

64. Coating seeds with a diversity of microorganisms
Working hypothesis:
• Solid compost can suppress Pythium aphanidermatum,
mediated by microorganisms and microbial byproducts
• Non-aerated compost extracts exhibit similar levels of
disease suppression – microbially-mediated
• Freeze-drying the liquid extracts and then reconstitute
them – disease suppression occurs
Can we freeze-dry extracts into a powder to be coated
onto seeds for suppressing soil-borne plant pathogens?

65. Coating seeds with a diversity of microorganisms
1
43
2

66. Coating seeds with a diversity of microorganisms
Next steps:
• Coat cucumber seeds with a binder using standard
seed coating technologies
• Apply/stick the freeze-dried extract to the coated seeds
• Assess microbial viability
• Conduct disease bioassays

67. Coating seeds with a diversity of microorganisms
Project supported in part by:
Drs. Eric Nelson and Alan Taylor,
Department of Plant Pathology

68. Conclusions and disclaimer revisited
Disclaimer
• Not supporting one product, manufacturer, approach,
technique, over another.
• Only here to deliver valid information so that you may
make educated decisions regarding your pest and
disease management strategy.
Conclusions
• There are a number of tools for managing plant
diseases
• Follow the manufactures recommendations
• Anticipate and predict outbreaks
• Accurate identification will save time and money