Biological Control of Diseases in the Nursery...Biological Control of Diseases in the Nursery Julie...

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Biological Control of Diseases in the

Nursery Julie Graesch

Biological Program Manager – Insect Management

December 17th 1:55-2:45pm

Overview • IPM • General biopesticide info• Programs

– Foliar disease– Soil disease– Available solutions

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3Journal of Integrated Pest Management, (2019) 10(1): 12; 1–

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• Sanitation ‒Remove weeds‒Manage surrounding grounds‒Remove diseased plants and crop residues‒Do not re-use potting media ‒Wash hands regularly ‒Sanitize tools and equipment ‒Sanitize surfaces, pots/trays/containers‒ Filter and treat recycled irrigation water

Disease IPM

• Cultural – Obtain clean seed and plant material– Keep fungus gnats under control– Crop rotation– Irrigation – Soil solarization – Fertilization

• Other measures– Obtain proper diagnosis of disease

• Damping-off, wilt, crown and root rots – Host plant resistance – Pest biology – Preventive biofungicides– Rotation of registered fungicides for high disease pressure

Disease IPM

Scouting & Recordkeeping

• Log and track pest presence/populations• Current & past info on ID and location of pests• Evaluate treatment effectiveness• Invite consultants

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Photo credit: Griffin Sales

• Need to change your mindset• Biopesticides typically not chemicals• Do not expect to use the same way• Don’t always expect the same results

– Non-systemic– Pests don’t drop dead immediately– May not preform under high pressure

• Shelf life• Plant safety

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The Chemical Paradigm

Plant Safety• Biopesticides have not been tested

on all varieties or in all tank mixes‒Check compatibility

• Mineral oil and sulfur • Use caution when making

applications during bloom• Test on a small number of plants to

check for phytotoxicity

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Why Biopesticides1. Low REIs and PHIs2. Safer for workers, consumers, &

environment- Many exempt from tolerances and MRLs

3. Reduced resistance to synthetic pesticides

4. Improve efficacy of chemicals5. Improve plant, soil and environmental

health over time with continued use6. Consumer demand

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Biopesticides Can…

• Be used to help prevent disease – Sometimes curative

• Manage disease at low to moderate pressure

• Trigger induced plant resistance• Manage chemical residues • Help prevent loss

– Season long and after dormancy• Produce healthier more productive crops • Help provide quicker turns• Manage diseases via multiple MOA

Multiple Modes of Action: Trichoderma 1. Antagonistic metabolites

• Bioactive compounds: antibiotics, anti-fungal peptides/proteins, enzymes, biosurfactants, specific toxins, etc.

2. Competition • Nutrients and niche in soil and plant

surfaces3. Rhizosphere competence

• Form of niche competition• Physically and biochemically blocking

access to root systems4. Predation / Hyperparasitism

• Pathogen as a food source• Physically attacking, infecting and/or

consuming by force, bioactive compounds, and/or digestive enzymes

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Biopesticides Can't…• Offer 100% protection• Cure diseases and insect pests• Work in environmental extremes• Work at high disease pressures• Last indefinitely

– Defined shelf lives and storage conditions– Frequent applications, especially on foliage

Factors Affecting Biopesticide Efficacy • IPM program

– Tank-mixing or rotation with synthetic fungicides• Active ingredient • Pathogen species • Pathogen incidence and severity• Rate • Application interval• Potting medium • Fertility regime

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• Preventative‒Diseases: At first

detection or when conditions are optimal for pathogen development‒Insects: As early as

possible upon detection or before economic threshold is reached

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Factors Affecting Biopesticide Efficacy Application Timing

Factors Affecting Biopesticide Efficacy

Coverage

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• Incorrect timing and poor coverage are primary causes of biopesticide failure

• Directed spray nozzles –Hydraulic sprayers–Backpack sprayers–Cold-foggers

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Factors Affecting Biopesticide

Efficacy Shelf Life

Many biopesticides are living organisms

• Physical compatibility– Jar test– Avoid multiple

inputs• Spore viability

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Factors Affecting Biopesticide Efficacy

Chemical Compatibility

BCA Compatibility

• Varies with biopesticide/chemical

• Compatibility guides • Companies/consultants

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Disease AI Insect AIBacillus sppStreptomyces sppPseudomonas sppExtract of SwingleaUlocladium oudemansiiCopperHyrdogen Dioxide Potassium bicarbonate

Beauveria bassianaMetarhizium anisopliaeIsaria fumosoroseaMineral Oil AzadirachtinPyrethrinsBurkholderia sppChromobacterium subtsugae

TrichodermaMycorrhizae Bacillus sppStreptomyces sppPseudomonas sppPlant proteins/amino acids Extract of SwingleaHyrdogen Dioxide

Beneficial Nematodes AzadirachtinBeauveria bassiana Plant extracts

Foliar

Root

Developing a Program

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Programs:Decision-Making Considerations

• Product cost‒ Cost per application:

• product, labor, and equipment‒ Number of applications per crop‒ Number of diseases controlled by

product

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Programs:Decision-Making Considerations

• Direct and indirect benefits‒ Cost savings

• Same or improved efficacy‒ Increased productivity:

• low REI, low/no PHI‒ Greater plant safety ‒ Greater worker safety‒ Lower resistance to conventional

fungicides and insecticides‒ Compatibility with other inputs

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Developing or Modifying a Program• Preventive: exclusion, sanitation, environment• Properly ID, don’t assume• Advice from manufacturers, growers, extension & consultants

– No one program fits all• Identify gaps in your program

– Efficacy– Resistance– Compatibility– Safety– Convenience– Market– Labor

How do you measure these?

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• Test new products on a small scale – Set-up a good comparison– Integrate vs. replace

• Document your tests– Keep track of what, how, when– Record what you see and experience– Photos: the good, the bad, the surprises

Developing a Program – Cont.

Adding Products to your Current Program • Current rotation program products• Is this a new MOA• Does the new product offer

– Efficacy– Lower REI– Plant or worker safety – Environmental safety – Broad or narrow spectrum – Application considerations – Resistance management

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Define what Success looks like

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Foliar Programs (Preventive)

Initial Spray(single or tank mix)

Biopesticide Spray

Rotation Partner

Biopesticide Spray

Rotation Partner

Basic Biological Program

General Rotation Program

Dip (first true leaves and/or transplant)

Dip (first true leaves and/or

transplant)

Products with multiple MOALow pressure Short turns

Incorporate BCAs

Biopesticide spray before harvest

Repeat ApplicationsApplication interval

depends on product & pressure

Biopesticide spray before harvest

Biopesticide Spray

Products with multiple MOAApplication interval depends on product and pressure

Single or tank-mixedLonger turns

Incorporate BCAs

How you start the program will depend on disease pressure

at season start

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Untreated Check

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ffect

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• Treatments applied I=7 DAP, II=14 DAP, III=21 DAP, IV=28 DAP, V=35 DAP • Treatments applied in 40 gal water per acre. Disease evaluation 42 DAP

• Powdery mildew: Sphaerotheca fuliginea and Erysiphe cichoracearum

Squash

University of FloridaHomestead, FL, 2009

97% Reductionin Leaf Surface

Affected

Procure®8oz/a

biweekly

Regalia®

1% v/vweekly

Actinovate®12 oz/aweekly

Regalia® 1% v/vAlt.

Procure 8oz/aweekly

Actinovate 12 oz/aAlt.

Procure 8oz/aweekly

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Biofungicides Used Early and in a Program with Complementary Fungicides Provides Powdery

Mildew Control in Squash – Pam Marrone

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Soilborne Disease Programs Preventive & Knockdown

Pythium, Fusarium, Rhizoctonia diseasesInitial Drench

WP, WDG, L, etc.Single or tank-mix

Pre-plant Incorporation (G) Container/tray bath WP, WDG, L, etc.

Repeat Drench Applications

2-12-week IntervalsDepends on product

DipSeeding, sticking

or transplantBiopesticide Drench

before Shipping

Chemical Knockdown Drench Alone or tank-mixed with

biofungicide

Chemical KnockdownTransplant

Pre-Treatment

5. Define what success looks like

Tips for Developing Your Own Program

5. Define what success looks like

Tips for Developing Your Own Program

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Julie GraeschBiological Program Manager – Insect Management

jgraesch@bioworksinc.comCell: 515-370-2299