Insect Management in Tomatoes & Peppers

Dr. Ayanava MajumdarExtension Entomologist (Peanuts, Vegetables)

State SARE Coordinator (Auburn U)Alabama Cooperative Extension System

Cell phone: 251-331-8416Email: bugdoctor@auburn.edu

AFVG Conf., February 11, 2012

What is it?Potato aphid, Macrosiphum euphorbiae

Green peach aphid, Myzus persicae

Monitoring/scouting techniques:Sample ten plants in several locationsYellow sticky traps at edge of fieldLike cool, dry weatherWatch for ants and lady beetlesET = 50% leaves with aphids

Host range: 40 host plants

What is it?Onion thrips, Thrips tabaci

Tobacco thrips, Frankliniella fusca

Monitoring/scouting techniques:Use sticky cards (yellow, blue)Bag and shake techniqueNo action thresholdUse resistant varieties (BHN 444, 589, 640, Bella Rosa)

Tomato spotted wilt destroys plantsHost plants: tomato, peanuts, cotton, beans

What is it?Monitoring/scouting techniques:

Monitor level of defoliation

Sample small plants with sweep net during morning hours

Observe activity of parasitoids, predators (sweep net)

ET = 5-10% defoliation early season, 25-30% defoliation mid-season

Flea beetles (many species)

Host plants: potato, tomato, peppers, broccoli, cabbage, okra, etc.

What is it?Monitoring/scouting techniques:

Start looking on border rows

Scout intensely short crop (<6 inch)

ET = 5 beetles per 10 seedling or 10% defoliation in short crop

Colorado potato beetle, Leptinotarsa decemlineata

Larva of lady beetle (beneficial insect!)

What is it?Monitoring/scouting techniques:

Examine green fruit, stem terminals

Scout for egg masses or larvae

Use pheromone traps to detect first flight; ET = 5-10 moths per night when temp. is <85F

ET is ½ if temp. is >85F

Tomato fruitworm, Helicoverpa zea

Tobacco budworm, Heliothis virescens

Host plants: tomato, cotton, soybean, corn (16 host plants)

What is it?Monitoring/scouting techniques:

Use a sweep net

Use pheromone trap (expensive? cumbersome?)

Intensify scouting at fruit setting

ET = 0.25 bugs per 10 plants (green fruit stage)

Southern green stink bug, Nezara viridula

Brown stink bug, Euschistus servus Lygus bug, Lygus

lineolarisStink bug feeding injury

Host: >52 plants

What is it?

Leptoglossus phyllopusLeptoglossus gonagra

Leptoglossus zonatus

Leaffooted bugs can cause fruit drop

What is it?• Caterpillars have an inverted Y

mark on head

• 4 black warts on 8th abdominal segment

• Curl up when disturbed

• Eats leaves and fruits

• Moths can be detected using pheromone traps

• Overwinters in Gulf coast

• Host range: sweet corn, tomato, peppers

• Premature drop & fruit rot

Fall armyworm, Spodoptera frugiperda

• Polyphagous insect (tomato, pepper, cotton, soybean, alfalfa)

• Have many wild hosts – lambsquarter & pigweed

• Creamish or light-green caterpillar, 4 pairs of prolegs

• Black spot on thorax just above the leg

• Early instars feed voraciously

• Moths are attracted to weak plants

What is it?

Damage to pepper plant

Beet armyworm, Spodoptera exigua

What is it?• Overwinter as pupae in soil

• Adults are hawk moths – rapid flyers

• Larva has 8 white stripes on side

• Larvae feed on foliage, then attack fruit

• Host range: tomato, pepper, eggplant, potato

• Repelled by marigold

• ET = >1 larva per plant

Tomato hornworm, Manduca quinquemaculata

What is it?• Adults resemble house flies but

have black markings on wings

• Females lay eggs on fruit, cause dimple and rotting

• Many types of peppers attacked

• Prefers cherry peppers

• Infested fruit turns red prematurely

• Major fruit drop and yield loss

• Monitor using yellow sticky trap

Pepper maggot, Zonosemata electa

What is it?Monitoring/scouting techniques:

Minor foliar pests (ET = 5 larvae per 10 plants)

Easy to collect & identify – shake and collect

Watch for sun scald on fruits, esp. 20% defoliation

Look for fecal pellets on leaves

Cabbage looper, Trichoplusia ni

Soybean looper, Pseudoplusia includens

VEGETABLE INSECTICIDES

CAUTION:

Use of product names does not mean endorsement by university!

Use cultural, mechanical, and other pest management tactics first

Insecticide use should be last resort!

Read pesticide labels – LABEL IS THE LAW.

Insecticide Mode of Action (MoA)

Receiving neuron

Sensory neuron

Neonicotinoids, Spinosyn (mimic neurotransmitter)

Cyclodienes, Pyrethroids (act on receiving neuron)

Carbamates, OP (act in the synaptic gap)

Inhibit enzyme that breaks down neurotransmitter

Flow of info

Insecticide Resistance Action Committee (IRAC): 28 MoA classification

Trends in synthetic chemistries

• Early insecticides were short chain>>quick activation• New insecticides: need “activation” by insect enzyme

systems (target-specific)

CarbarylMalathion

Zeta-cypermethrin Imidacloprid

Spinetoram

Chlorantraniliprole

Review of Insecticides/MoA (Open page 167 of Veg. Prod. Handbook)

Mode of ActionSt = Stomach poison; Co = Contact poison; Sys = Systemic action; In = Insecticide; Mi = Miticide

Arrangement: Least toxic to most toxic

Target InsectsFB = Flea beetle; CPB = Colorado potato beetle; CEW = Corn earworm; FAW = Fall armyworm; SVB = Squash vine borer; Aph = Aphids; Thr = Thrips; WF = Whiteflies; ECB = European corn borer; CB = Cucumber beetle; SB = Stink bug, SqB = Squash bug; CW = Cutworms; MGT = maggots; WW = Wireworms; CL = Cabbage looper

Common name Product Pesticide type OralLD50 (mg/kg)

Best against

Carbaryl Sevin D/S In, Ac (St, Co) 300 FB, FAW, SVB

Methamidophos Monitor 4L In, Ac(Sys) 16 Aph, Thr, BAW

Methomyl Lannate 40SP

In, Ac (Sys, Co)

17 Thr, BAW

IRAC Chemical class: 1A (Carbamates)

MoA: inhibitor of enzyme (AChE), hyperexcites insects, nonselective

Common name

Product Pesticide type OralLD50 (mg/kg)

Best against

Malathion Malathion In (Co) 1000+ FB, CB, SqB, SB??

Acephate Orthene In (Sys) 800+ FAW, Aph, Thr

Diazinon Diazinon (RUP) I (Co) 400 WW, MGT, SqB

Chlorpyrifos Lorsban 15G In (Co) 95 MGT, CW, WW, FAW

IRAC Chemical class: 1B (Organophosphates) MoA: inhibitor of enzyme (AChE), hyperexcites insects

Common name Product Pesticide type

OralLD50 (mg/kg)

Best against

Endosulfan ThionexThiodan (GUP)

In, Ac (Co)

18-160 FB, SB, SqB

IRAC Chemical class: 2A (Cyclodienes)

MoA: Block the action of neurotransmitter, hyperactivity

Common name Product Pesticide type

Oral LD50 (mg/kg)

Best against

Cyfluthrin Baythroid XL In (Co, St) 1200+ ImCW, SqVB, CW, SB

Gamma cyhalo Proaxis 0.5EC In (Co) - FB, CB, ECB, ImCW, SqVB, CW

Fenpropathrin Danitol 2.4EC In, Ac (Co, St)

450 ImCW, SqVB, SqB

Zeta-cyper Mustang Max 0.8 EC

In (Co) 150-400 FB, CW, CB, SB, ImCW, SqVB

Bifenthrin Brigade 2EC In, Ac (Co) 54 FB, CB, ImCW, SqVB, CW

IRAC Chemical class: 3A (Pyrethroids) MoA: Act on sodium channels (receiving neuron)Contact/stomach: use for quick knock-down, nonselective

Asana® XL insecticide

Common name Product Pesticide type OralLD50 (mg/kg)

Best against

Thiamethoxam Platinum SC In (Sys) >5000 Aph, FB, CB, SB

Dinotefuran Venom 70SG In (Sys) >5000 FB, CPB, CB, SB, WF

Clothianidin Belay 3G In (Sys) 4700 FB, CPB, SqB, CB

Imidacloprid Admire 1.6F

Provado F

In (Sys, Co, St)

450 FB, CPB, Aph, SB

CPB, CB, Aph, ThrAcetamiprid Assail 30SG In (Sys) - Aph, CPB, Thr

IRAC Chemical class: 4A (Neonicotinoids) MoA: Mimic neurotransmitter at neuromuscular joints, hyperactivity Systemic action: many weeks of protection against pests, apply early

Assail® insecticide

Results of 1999 tomato test at Tifton, GA in terms of main plot (BHN444 resistance and silver reflective mulch) and subplot (different length periods of insecticide control of

thrips) effects on number of thrips, % TSWV, and $ yield per acre, respectively.

BHN444-silver mulch 47 b 28% b $7,233 a

Sunny Hyb.-silver mulch 49 b 57% a $4,721 ab

Sunny Hyb.-black mulch 64 a 67% a $3,602 b

Admire + four weeks of foliar sprays 53 b 28% c $6,685 a

Admire + two weeks of foliar sprays 57 b 56% ab $6,102 a

Admire + eight weeks of foliar sprays 13 c 44% ab $5,781 a

Admire + one week of foliar sprays 70 a 58% ab $3,777 b

Untreated check 73 a 67% a $3,580 b

David Riley, UGA, http://wiki.bugwood.org/Thrips_and_Spotted_Wilt_Management_in_Tomato

Systemic insecticide (imidacloprid) reduces virus transmission in tomatoes

Common name Product Pesticide type

OralLD50 (mg/kg)

Best against

Spinosyn A, D Entrust (SpinTor phase out)

In (St) >5000 CPB, ImCW, CEW, FAW, BAW, CL, DBM

Spinetoram Radiant 1SC In (St) >5000 CPB, CEW, ECB, ImCW, CL, Thr

IRAC Chemical class: 5A (Spinosyns) MoA: Mimic neurotransmitter, hyperexcite insects

Spinetoram (Radiant 1SC):• Microbial fermentation derivate• Application rate = 6-8 oz• Preharvest interval (PHI) = 1-3 days• Registered for many leafy veg., fruit crops, root crops, etc.

Entrust: for ORGANIC producers

Common name Product Pesticide type OralLD50 (mg/kg)

Best against

Pymetrozine (9B) Fulfill 50WDG In (St) >5000 Aph, WF

Flonicamid (9C) Beleaf 50SG In(St) >2000 Aph

IRAC Chemical class: 9 (new chemistry)

MoA: Unknown; selective homopteran feeding blockers

Fulfill 50WDG (Syngenta):

• Selective insecticide for aphid control

• Good residual, rainfast

• Application rates low: 2-2.8 oz/acre product

• PHI = 0 days

Common name Product Pesticide type OralLD50 (mg/kg)

Best against

Chlorantraniliprole Coragen 1.67SC In (St, Co, Sys) >5000 CPB, CEW, ECB, FAW, BAW, CL, SqVB, SB

Flubendiamide Synapse 24WG In (Sys) >2000 CEW, ECB, CL, ImCW, BAW, FAW

IRAC Chemical class: 28 (new chemistry-diamides) MoA: Ryanodine receptor modulators (acts inside muscles)

Diamides:• Rapid inhibition of feeding, paralysis• Selective insecticides, contact/stomach action• No aphid or mite flaring• Appl. rate = 3-5 oz (Coragen), 2-3 oz (Synapse)• 1 day PHI

Growth Regulator Insecticides

Common name Product Pesticide type

OralLD50 (mg/kg)

Best against Less effective

Methoxyfenozide Intrepid 2F I (Co) >5000 CL, FAW, ImCW DBM, SqVB

Buprofezin Courier I, Mi (Co) >5000 WF

Pyriproxifen Knack I (Co) >5000 WF

IRAC Chemical class: 7C, 16, 17, 18

Growth regulators:• Methoxyfenozide forces molting, long-lasting, 4-10 oz, 1 day PHI

• Buprofezin inhibits chitin biosynthesis (homopteran), 9-13 oz, 7 day PHI

• Pyriproxifen mimics juvenile hormone (homop.), 8-10 oz, 14 day PHI

Organic Insecticide Research– Insecticide rotations– New formulations/delivery systems

Good rotation partners

General IPM Recommendations• Use pheromone traps (first detection is important)

• No substitute for scouting!

• Careful with insecticide generics (phytotoxicity)

• Rotate with newer insecticides, organic formulations

• Apply systemic insecticides early (timely)

• Use of the SE Vegetable Prod. Handbook

• Call ACES for help in insect ID & IPM

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Insect Management in Tomatoes & Peppers

Questions for Dr. A?

AFVG Conf., February 11, 2012