Biorational Insecticides in the Biorational Insecticides in the Landscape and Options for Turf Landscape and Options for Turf

Insect Pest ManagementInsect Pest Management

Eileen A. Buss, Ph.D.Associate Professor & Extension SpecialistDept. of Entomology & Nematology, UF/IFAS

eabuss@ufl.edu; 352-273-3976

Learning Objectives

Define “biorational insecticide”

Know the differences between conventional & biorational insecticides

Know the strengths / weaknesses of the different biorational insecticides

Be able to give a range of control options to your clients

Traditional InsecticidesTraditional Insecticides(Organophosphates & Carbamates)(Organophosphates & Carbamates)

Broadly toxicBroadly toxic

Affect systems common to both insects Affect systems common to both insects and vertebrates (e.g., nervous system) and vertebrates (e.g., nervous system)

Risk to non-target organisms (e.g., Risk to non-target organisms (e.g., beneficial insects, fish, birds, humans)beneficial insects, fish, birds, humans)

Secondary pest outbreaksSecondary pest outbreaks

Pest resurgences and resistancePest resurgences and resistance

What is a “Biorational” Insecticide?

An insecticide of natural origin that has little or no adverse effects on the environment or non-target organisms

How are Biorationals Different from Conventional Insecticides?

Different modes of action

Low use rate

More selective

Short residual activity

Low risk to humans, wildlife, and environment

Types of Biorational Insecticides

Botanicals Azadirachtin/neem, rotenone, sabadilla, pyrethrins/

pyrethrum, nicotine

Microbials Bacteria, fungi, nematodes

Protozoa and viruses – not commercially available

Others Insect growth regulators, molt accelerating

compounds, soaps, oils

Natural plant products extracted from Natural plant products extracted from commercially-grown plantscommercially-grown plants

Examples: azadirachtin/neem, rotenone, Examples: azadirachtin/neem, rotenone, sabadilla,sabadilla, pyrethrins/pyrethrum, nicotinepyrethrins/pyrethrum, nicotine

Botanical InsecticidesBotanical Insecticides

Azadirachtin / NeemAzadirachtin / Neem

From seeds of the tropical neem treeFrom seeds of the tropical neem tree Broad spectrum (e.g., caterpillars, Broad spectrum (e.g., caterpillars,

leafminers, thrips, whiteflies, mealybugs)leafminers, thrips, whiteflies, mealybugs) Active by contact or ingestionActive by contact or ingestion Feeding deterrent, interferes with molting Feeding deterrent, interferes with molting

in young insects, in young insects, Trade names: Margosan-O, Azatin, Bio-Trade names: Margosan-O, Azatin, Bio-

neem (used in greenhouses, landscapes)neem (used in greenhouses, landscapes)

RotenoneRotenone

Toxic alkaloid extracted from roots of Toxic alkaloid extracted from roots of a tropical legumea tropical legume

Used in garden dusts, flea powdersUsed in garden dusts, flea powders

Very toxic to fishVery toxic to fish

SabadillaSabadilla

From seeds of the sabadilla lillyFrom seeds of the sabadilla lilly

Trade names: Red Devil, Natural GuardTrade names: Red Devil, Natural Guard

No residue; breaks down quickly in lightNo residue; breaks down quickly in light

Target pests: caterpillars, leafhoppers, Target pests: caterpillars, leafhoppers, stink bugs, squash bugs, thripsstink bugs, squash bugs, thrips

Crop: vegetables, citrus, avocado, mangoCrop: vegetables, citrus, avocado, mango

Pyrethrum, PyrethrinsPyrethrum, Pyrethrins

Derived from chrysanthemum flowersDerived from chrysanthemum flowers

Low mammalian toxicityLow mammalian toxicity

Rapid “knockdown” of flying insects; paralyzes Rapid “knockdown” of flying insects; paralyzes CNSCNS

Synergized by piperonyl butoxide (PBO)Synergized by piperonyl butoxide (PBO)

Breaks down quickly in sunlight; no residualBreaks down quickly in sunlight; no residual

Expensive, but widely usedExpensive, but widely used

Pyrethroids (Group 3) Synthetic versions of pyrethrum, but with

enhanced properties Fast-acting, good knockdown Low mammalian toxicity; target selective for

insect nerves Broadspectrum contact insecticides used

against surface-feeding insects and mites (not systemic)

Usually applied at low rates on foliage or as root drenches in nurseries

Pyrethroids

Pyrethroids are generally not compatible with biocontrol programs (toxic to hymenopterans)

Pyrethroids have been associated with secondary pest outbreaks (e.g., spider mites), which results in more pesticide use to control those outbreaks

Pyrethrins and older pyrethroids exhibit greater toxicity at cooler temperatures; newer pyrethroids are more toxic at higher temps

Movement of Pyrethroids

Not very water soluble

Pyrethroids will bind to surfaces rather than run off

However, with their widespread use, several pyrethroids have been detected in California surface waters (Weston et al. 2004)

Microbial Insecticides

Products that contain pathogens or microbially-Products that contain pathogens or microbially-derived toxins or by-products that kill insectsderived toxins or by-products that kill insects

Bacteria

Fungi

Nematodes (not really a microbe…)

Protozoa

Viruses

Bacterial Insecticides

Spore-forming, rod-shaped bacteria in the genus Bacillus

Commonly occur in soils

Must be eaten to be effective

Bacillus thuringiensisBacillus thuringiensis (Bt) (Bt)

Bt var. kurstaki - used since 1950’s to Bt var. kurstaki - used since 1950’s to control leaf-eating caterpillarscontrol leaf-eating caterpillars

Produced commercially by fermentationProduced commercially by fermentation

VeryVery low vertebrate toxicity low vertebrate toxicity

Short residual in sunlightShort residual in sunlight

Works better against small larvae than vs. Works better against small larvae than vs. larger oneslarger ones

Other Bt strains are active against insects Other Bt strains are active against insects other than Lepidoptera (e.g., M-one for other than Lepidoptera (e.g., M-one for Colorado potato beetle control – Bt var. san Colorado potato beetle control – Bt var. san diego; Bt var. diego; Bt var. israelensisisraelensis to kill mosquito, to kill mosquito, fungus gnat, and black fly larvae)fungus gnat, and black fly larvae)

Milky Spore Disease(Bacillus popilliae)

Diseased (left) and normal (right) grubs

Dan Potter, Univ. of KY

ConserveConserve®® SC (Spinosad) SC (Spinosad)

Soil-dwelling bacterium, Soil-dwelling bacterium, Saccharopolyspora spinosaSaccharopolyspora spinosa

Contact and stomach poisonContact and stomach poison Residual up to 2 weeksResidual up to 2 weeks Caterpillars, thrips, fire antsCaterpillars, thrips, fire ants Labeled for use on greenhouses, Labeled for use on greenhouses,

nurseries, and all turfgrassesnurseries, and all turfgrasses

AvidAvid®® (Avermectin) (Avermectin)

Produced from Produced from Streptomyces avermitilisStreptomyces avermitilis

Slow actingSlow acting

Low mammalian toxicityLow mammalian toxicity

Leaf systemicLeaf systemic

Mites and leafminersMites and leafminers

FungiFungi

Spores grow on the insect cuticle, then hyphae penetrate the cuticle and grow inside the body, soon killing the insect

Fungus infected chinch bug (left) & whiteflies (right)

Metarhizium anisopliae

Called “green muscardine disease” The cadaver’s cuticle becomes red. In high

humidity, a white mold grows on the cadaver, which turns green as spores are produced.

Fungus is naturally in soil & infects insects

Infects ~200 arthropod species (used for ticks, used for ticks, beetles, flies, gnats, thripsbeetles, flies, gnats, thrips), but is safe for use around mammals

Beauveria bassiana (Naturalis T, Botanigard)

Called “white muscardine disease”Called “white muscardine disease”

Used for aphids, whiteflies, mealybugs, Used for aphids, whiteflies, mealybugs, mealybugs, ticks, beetles, flies, gnats, thripsmealybugs, ticks, beetles, flies, gnats, thrips

Greatest mortality in hot and humid conditionsGreatest mortality in hot and humid conditions

Fungi do not need to be ingested to workFungi do not need to be ingested to work

Infected insects die within a few days to a weekInfected insects die within a few days to a week

Avoid tank-mixing with fungicidesAvoid tank-mixing with fungicides

Improving the Chance of Infection

Use of an abrasive (e.g., diatomaceous earth) along with Beauveria may increase insect mortality by weakening the insect cuticle

Entomopathogenic NematodesEntomopathogenic Nematodes

Microscopic, unsegmented wormsMicroscopic, unsegmented worms Attack various insects (e.g., soil insects, Attack various insects (e.g., soil insects,

wood borers)wood borers) Enter host’s body through mouth and Enter host’s body through mouth and

spiracles, release and feed on bacteria, spiracles, release and feed on bacteria, reproduce inside insect bodyreproduce inside insect body

Don’t damage plants – have different Don’t damage plants – have different mouthpartsmouthparts

Entomopathogenic NematodesEntomopathogenic Nematodes

Several species (Several species (SteinernemaSteinernema spp., spp., HeterorhabditisHeterorhabditis spp.) occur spp.) occur naturally in the soil, but some can naturally in the soil, but some can be purchasedbe purchased

Some insecticides, like Some insecticides, like imidacloprid (Merit), may slow imidacloprid (Merit), may slow grub behavior down and make grub behavior down and make them more susceptible to them more susceptible to nematode infectionnematode infection

Molt-Accelerating CompoundsMolt-Accelerating Compounds

Mimic the action of the insect molting Mimic the action of the insect molting hormone, ecdysone (Mach 2hormone, ecdysone (Mach 2®®, Confirm, Confirm®®))

Low vertebrate toxicityLow vertebrate toxicity

Ingestion forces a premature, lethal molt of turf Ingestion forces a premature, lethal molt of turf grubs and caterpillarsgrubs and caterpillars

Chitin Synthesis InhibitorChitin Synthesis Inhibitor

TalusTalus®® IGR (buprofezin) IGR (buprofezin)

Active by contact, ingestion, or vaporActive by contact, ingestion, or vapor

Target pests: mealybugs, whiteflies, Target pests: mealybugs, whiteflies, scales, leaf- and plant hoppersscales, leaf- and plant hoppers

Sites: greenhouse, nurseries, Sites: greenhouse, nurseries, ornamentals, fruit and nut treesornamentals, fruit and nut trees

Horticultural OilsHorticultural Oils

Highly refined petroleum-based oilsHighly refined petroleum-based oils

Useful vs. small or slow-moving, soft-Useful vs. small or slow-moving, soft-bodied pests, (aphids, leafhoppers, bodied pests, (aphids, leafhoppers, scales, overwintering eggs, mites)scales, overwintering eggs, mites)

May prevent gas exchange through egg May prevent gas exchange through egg membranes, clog insect mouthparts, membranes, clog insect mouthparts, deter feeding or egg-layingdeter feeding or egg-laying

Horticultural OilsHorticultural Oils

Advantages:Advantages: Non-toxic to vertebratesNon-toxic to vertebrates

No resistanceNo resistance

Disadvantages:Disadvantages: Must contact insect with sprayMust contact insect with spray

No residualNo residual

Potential for Potential for phytotoxicityphytotoxicity

PhytotoxicityPhytotoxicity

Insecticidal SoapsInsecticidal Soaps Made from salts in the fats and oils Made from salts in the fats and oils

of animals and plantsof animals and plants (very safe) (very safe)

Kill by disrupting insect cuticleKill by disrupting insect cuticle

Contact toxicity only – no residualContact toxicity only – no residual

Good vs. small, soft-bodied insects Good vs. small, soft-bodied insects (aphids, caterpillars, crawlers)(aphids, caterpillars, crawlers)

M-Pede, Rose and Flower Insect M-Pede, Rose and Flower Insect Control, and Safer Yard & GardenControl, and Safer Yard & Garden

Insecticide Options for Turf Pests

Caterpillar Control OptionsNeonicotinoids Arena, Meridian, MeritCombination products Allectus (Talstar + Merit)

Aloft (Talstar + Arena)Pyrethroids Talstar / Onyx, Astro, Scimitar,

TempoIGRs/Molt Accelerating Compounds

Dimilin, Mach2

OrganophosphatesCarbamates

DyloxSevin

Anthranilic diamides AceleprynOxadiazine ProvauntMicrobials B.t. var. kurstaki, Conserve

* Trade names are only used as examples and are not intended as endorsements. Other products may be labeled against this pest group.

Chinch Bug Control Options

Neonicotinoids Arena, Meridian, Merit

Combination products Allectus (Talstar + Merit)Aloft (Talstar + Arena)

OrganophosphatesCarbamates

DyloxSevin

Pyrethroids Talstar / Onyx, Astro, Scimitar, Tempo

Microbials Beauveria, Metarhizium

* Trade names are only used as examples and are not intended as endorsements. Other products may be labeled against this pest group.

Grub Control OptionsNeonicotinoids Arena, Meridian, Merit

Combination products Allectus (Talstar + Merit)Aloft (Talstar + Arena)

IGRs/Molt Accelerating Compounds

Mach2

OrganophosphatesCarbamates

DyloxSevin

Anthranilic diamides Acelepryn

Microbials Milky spore disease

Insect parasitic nematodes Steinernema spp.Heterorhabditis spp.

* Trade names are only used as examples and are not intended as endorsements. Other products may be labeled against this pest.

Mole Cricket Control

Preventive: Treat young nymphs in May/June,

soon after peak egg hatch Chipco Choice/TopChoice, pyrethroids,

neonicotinoids, combination products

Curative: Treat after damage occurs, usually

summer, fall, or spring Baits (Dursban, Advion) Spot treatments (Orthene, others)

If a tree falls in the forest and no one is around to hear it,

does it make a sound?

Do insecticides work if there are no

insects present to control?

What should we recommend?

Determine the client’s goals and any Determine the client’s goals and any site limitations (e.g., proximity to water, site limitations (e.g., proximity to water, lack of irrigation, steep slope)lack of irrigation, steep slope)

Rule out or consider non-chemical Rule out or consider non-chemical options firstoptions first

Several products may have similar Several products may have similar efficacy against certain pestsefficacy against certain pests

Product cost is a major factorProduct cost is a major factor