IPM– an Eco-Friendly Approach to

Disease Control

Dr. Yonghao LiPhone: 203-974-8601; Email: Yonghao.Li@ct.gov

Spring Bedding Plants – February 2016

Integrated Pest Management (IPM)

IPM

A systematic approach to solving pest problems by

applying our knowledge about pests to prevent them from

damaging crops

Benefits

Reduce pests

Reduce pesticide applications

Save money

Protect human health and environment

Integrated Pest Management (cont.)

Steps of IPM program

Identify key diseases

Pathogens, etiology, damages

Monitor disease development and keep records

Dates, conditions, severity

Determine the potential for economic loss

Percentages of affected units vs. economic losses

Set action thresholds

Local and systemic infections

Choose the proper management methods

Exclusion, eradication, resistance, protection

Evaluate the effectiveness of the management plan

Input, outcome

Integrated Pest Management (cont.)

Integrated Pest Management (cont.)

Minimizing Fungicide Resistance

Follow good plant health practices

Incorporate IPM system into routine cultural practices

Use the recommended doses

Increased doses increase selection for fungicide resistance

Minimize the number of fungicide treatments per season

Do not rely solely on one fungicide with a site specific

mode of action – fungicide rotation

Tank-mix fungicides with different action modes

Downy mildew and Phytophthora

foliar and root diseases

Downy mildew, rust, Botrytis, powdery mildew,

fungal leaf spots, Rhizoctonia damping-off

Injury was observed on African violets and Rieger begonia.

Foliar spray or soil drenchFoliar spray or soil drench

KEY USES

More than 45 plant species including:

African violet

Aster

Azalea

Begonia

Pansy

Petunia

Poinsettia

Foliar spray, pre-potting mix, or soil drench

Fungal leaf spot, rust, Botrytis, powdery

mildew, downy mildew,

Indoor and outdoor grown ornamentals,

herbs, and vegetables

• Powdery mildew

• Anthracnose

• Bacterial leaf spot

• Botrytis blight

• Pythium

• Downy mildew

• Rust

• Late blight

• Phytophthora root rot Foliar spray or soil drench

Outline

Foliar diseases

Botrytis blight

Downy mildew

Bacterial and fugal leaf spots

Virus diseases

Root diseases

Thielaviopsis root rot

Pythium root rot

Botrytis Blight

Courtesy of Leanne Pundt

Geranium Lily

Botrytis Blight (cont.)

Courtesy of Leanne Pundt

New Guinea Impatiens Bacopa

Botrytis Blight (cont.)

Heuchera Zinnia

Botrytis Blight (cont.)

Poinsettia

Botrytis Blight (cont.)

Begonia

Calibroachoa

Courtesy of Leanne Pundt

Development of Botrytis Blight

A wide host range (over 200 plant species)

Airborne pathogen (conidia)

Survive in plant debris (mycelium) and soil (sclerotia)

many years

Infections favored by cool and rainy weather

conditions

Start from old and weaken plant tissues

Management of Botrytis Blight

Cultural practices

Adequate space between plants

Water plants in early morning

Avoid dramatic changes in day/night temperature

Remove faded flowers and diseased leaves

Chemicals and biological control agents

Sever damages last several years

Cool and wet spring

Early application for prevention

Fungicide resistance

Management of Botrytis Blight (cont.)

Active Ingredient FungicideFRAC

Code

Risk of

Resistance

Thiophanate-methyl Cleary’s 3336 1 High

Azosystrobin Heritage 11 High

Iprodione Chipco 26019 2 Medium to high

Polyoxin D zinc salt Affirm 19 Medium

Fludioxonil Medallion, Emblem 12 Low to medium

Fenhexamid Decree 17 Low to medium

Mancozeb Dithane M3 Low

Chlorothalonil Daconil Ultrex M5 Low

Cyprodinil & Fludioxonil Palladium 9 & 12

Pyraclostrobin + Boscalid Pristine, Pageant 7 & 11

Solatenol + Azoxystrobin Mural 7 & 11

Fluoxastrobin + Tebuconazole Fame+T 11 & 3

Fungicide Trial of Botrytis Blight of Geranium

Treatment Active Ingredient FRAC

Code

Disease

Severity

Disease

Incidence

Untreated control 4.8 i 39.4 d

BAS 703 01F Pyraclostrobin +

Fluxapyroxad

11+7 1.6 ab 7.3 ab

Pageant Pyraclostrobin +

Boscalid

11+7 3.0 def 17.2 abc

Tourney Metconazole 3 1.8 abc 9.0 ab

Emblem Fludioxonil 12 2.2 bcd 7.5 ab

Affirm Polyoxin D zinc salt 19 1.2 a 7.0 ab

Experiment was conducted Mary Hausbeck at MSU in 2015. Plants were inoculated

with Botrytis cinerea and fungicides were applied at 14 days intervals

Management of Botrytis Blight (Cont.)

Fungicide Active IngredientFRAC

Code

Risk of

Resistance

Camelot

Cuprofix

Phyton 27

Copper M1 Low

Serenade

Cease Bacillus subtilis 44 N/A

Mycostop Streptomyces griseoviridis N/A N/A

KleenGrowQuaternary ammonium

chlorideN/A N/A

Actigard Acibenzolar-S-methyle P1 N/A

Downy Mildew

Courtesy of Leanne Pundt Courtesy of Leanne Pundt

Upper surface Lower surfaceRudbeckia

Downy Mildew (cont.)

Lamium Coleus

Downy Mildew (cont.)

Courtesy of Leanne PundtCourtesy of Leanne Pundt

Upper surface Lower surfaceBasil

Downy Mildew (cont.)

Impatiens

Development of Downy Mildew

Host-specific pathogens

Water mold

Cool temperature and high humidity

Survive in living tissues

Cuttings and seedlings

Seed (basil downy mildew)

Air-borne

Management of Downy Mildew

Exclusion

Use disease-free seed or plant materials

Basil downy mildew

Cuttings and plugs

Resistant variety

Resistance vs. market

Cultural practices

Reduce leaf wetness period

Adequate spacing

Vent and heat before evening (< RH 85%)

Chemicals

Scouting for diseases

Basil: https://docs.google.com/spreadsheets/d/1JgKGmCP-0I2A03J0BG2EafNctvQTiaUUnbqJbYfQhVk/edit?pref=2&pli=1#gid=0

Rotation and coverage

Fungicides for Downy Mildew Control

Active Ingredient FungicideFRAC

Group

Risk of

Resistance

Mefenoxam Subdue MAXX 4 High

Azoxystrobin Heritage 11 High

Fenamidone Fenstop 11 High

Trifloxystrobin Compass O 11 High

Cyazofamid Segway, Ranman 21 Mid

Oxathiapiprolin Segovis U15 Mid-High

Mandipropamid Micora, Revus 40 Low-Mid

Dimethomorph Stature 40 Low-Mid

Fluopicolide Adorn 43 Low-Mid

Ethyl phosphonate Aliette 33 Low

Boscalid+pyraclostrobin Pageant 7 & 11

Azoxystrobin+benzovindiflupyr Mural 11 & 7

Mancozeb+thiophanate-methyl Zyban 1 & M3

Bacterial Leaf Spot of Zinnia

Leanne Pundt

Fungal and Bacterial Leaf Spots on Poinsettia

Alternaria leaf spot Bacterial leaf spot

Latex Eruption of Poinsettia

Alternaria Leaf Spot and Flower Blight of Marigold

Development of Fungal and Bacterial Lear Spot

Host-specific

Genus or family

Survive in plant debris and seed

Few months to several years

Dispersed via wind and water splash

Bacteria – water splash

Fungi – wind and water splash

Wet and highly humid conditions (water film)

Spore germination and penetration

Management of Bacterial and Fungal Leaf Spot

Seed treatment

Seed borne diseases

Cultural practice

Remove and destroy infected plant materials

Avoid overhead irrigation whenever possible

Avoid handling plants when they are wet

Reduce relative humidity in greenhouses

Scouting for diseases

Chemicals, biocontrol agents, and biorational

products http://ipm.uconn.edu//pa_greenhouse/

Impatiens Necrotic Spot Virus (INSV)

Begonia Cineraria

Impatiens Necrotic Spot Virus (INSV) (cont.)

Pepper Eggplant

Tomato Spotted Wilt Virus (TSWV)

Chrysanthemum Iris

TMV and Iron Deficiency on Petunia

TMV Iron deficiency

Management of Virus Diseases

Exclusion

Clean, disease-free seed and plant materials

Sanitation

Remove and destroy infected plants

Handle healthy plants first, then diseased plants

Insect control

Most plant viruses were transmitted by insects

Weed control

Wide host ranges of viruses

Thielaviopsis Root Rot

Salvia Salvia

Thielaviopsis Root Rot (cont.)

Courtesy of Leanne Pundt

Phlox Lavender

Thielaviopsis Root Rot (cont.)

Calibroachoa Chlamydospores in root tissues

Pythium Root Rot

Gerbera daisy Lupine

Pythium Root Rot (cont.)

Poinsettia Lupine

Pythium Root Rot (cont.)

http://hyg.ipm.illinois.edu/article.php?id=208

Development and Management of Root Rot

Development Wide host range

Soil-borne pathogens

Spread by running water, tools, and soil

Management

Sanitation

Clean floors and other structures using a pressure washer

Disinfest structures and tools

Water management

Avoid excess water

Fungicide application

Early application and rotation *

Fungicides for Pythium and Thielaviopsis Root Rot

Pathogen Fungicide Active IngredientFRAC

Code

Risk of

Resistance

Pythium Subdue MAXX Mefenoxam 4 High

Heritage Azoxystrobin 11 High

FenStop Fenamidone 11 High

Empress Pyraclostrobin 11 High

Segway Cyazofamid 21 Med-High

Truban; Terrazole Etridiazole 14 Low-Med

Adorn Fluopicolide 43 N/A

Alude Phosphorous acid 33 Low

Thielaviopsis 3336 F Thiophanate-methyl 1 High

Emblem, Medallion Fludioxonil 12 Low-Med

Banrot Thiophanate-methyl

+ eridiazole

1+14

Fungicide Resistance

http://msue.anr.msu.edu/news/pythium_root_rot_in_the_greenhouse

October 2013 by Mary Hausbeck

Thank You!

Questions?