use of biopesticides

Use of Biopesticides for the Control of Insect Pests

Use of Biopesticides for the Control of Insect Pests

Dr. R.C.SihagDr. R.C.SihagProfessorProfessor

Department of Zoology & Department of Zoology & Aquaculture,Aquaculture,

CCS Haryana Agricultural University,CCS Haryana Agricultural University,Hisar-125004, IndiaHisar-125004, India

Table:1 History of Table:1 History of Development of PesticidesDevelopment of Pesticides

YEAR CHEMICAL LOCATION

900 ARSENICALS CHINA

1090 TOBACCO & SOAPS EUROPE

1800 PYRETHRINS CAUCASUS

1867 PARIS GREEN U.S.A.

1883 BOURDEAUX MIXTURE FRANCE

MODERN ERA

1939-40 DDT-TOXIC PROPERTIES DISCOVERED SWITZERLAND

1941-42 BHC- TOXIC PROPERTIES DISCOVERED FRANCE, U. K.

1942-60 CYCLODIENES, CARBAMATES AND EUROPE, U. S. A.

OP COMPOUNDS

1962 RACHEL CARSON'S BOOK SILENT U. S. A.

SPRING APPEARS

1970- 71 TRIALS AGAINST DDT BEGINS SWEEDEN

1975-80 SYNTHETIC PYRETHROIDS JAPAN

1980-81 CHITIN INHIBITORS U. S. A.

1981 BIO-PESTICIDES AND TRANSGENIC U. S. A..

ONWARDS PLANTS

BiopesticidesBiopesticides► Constitute the pest control agents of Constitute the pest control agents of

biological origin biological origin ► Microbials: bacteria, fungi, viruses, protozoaMicrobials: bacteria, fungi, viruses, protozoa► Pheromones/semiochemicals: message-Pheromones/semiochemicals: message-

bearing substances produced by plants and bearing substances produced by plants and animals (interfere with mating or disrupt animals (interfere with mating or disrupt pest insect behaviour)pest insect behaviour)

► Invertebrate Biological Control Agents Invertebrate Biological Control Agents (macro organisms): parasitoids, predators (macro organisms): parasitoids, predators and parasitesand parasites

► Botanical pesticidesBotanical pesticides► Transgenic cropsTransgenic crops

Table:2 Table:2 Agrochemicals Vs. Agrochemicals Vs. BiologicalsBiologicals

Factors Agrochemicals Agri-biologicals

Cost effectiveness Cheap but increased spraying cost

Costlier but reduced number of applications

Persistence and residual effect

High Low, mostly Bio-degradable and self perpetuating

Knockdown effect Immediate Delayed

Handling and Bulkiness Easy but danger and Hazardous

Bulky : Carrier basedEasy : Liquid formulation

Pest resurgence More Less

Resistance More prone Less prone

Effect on Beneficial flora At times destruction of friendly pest

Less harmful on beneficial pests

Target specificity Mostly broad spectrum Mostly host specific

Waiting time Very high Almost nil

Nature of control Curative Preventive

Shelf life More Less

(Source : agriculture Today. Nov. 2005)

Microbial Microbial insecticidesinsecticides

► Consist of a microorganism as the active Consist of a microorganism as the active ingredient (e.g., bacterium, fungus, virus or ingredient (e.g., bacterium, fungus, virus or protozoan)protozoan)

► About 3000 reported to cause diseases in About 3000 reported to cause diseases in insectsinsects

► Viruses isolated from 1000 species of insectsViruses isolated from 1000 species of insects► More than 100 bacteria identified as pathogensMore than 100 bacteria identified as pathogens► Over 800 fungal species belonging to 100 Over 800 fungal species belonging to 100

genera recognizedgenera recognized► More than 100 protozoans identified as More than 100 protozoans identified as

pathogenspathogens

VirusVirus►Set of one or more nucleic acid Set of one or more nucleic acid

template molecules, normally encased template molecules, normally encased in a protective coat or coats of protein in a protective coat or coats of protein or lipoprotein that is able to organize or lipoprotein that is able to organize its own replication only within suitable its own replication only within suitable host cellshost cells

Table:3 Table:3 Characteristics of Viruses Characteristics of Viruses found in insectsfound in insects

Virus Virus Nucleic acidNucleic acid Virus Virus particleparticle

Inclusion body Inclusion body shapeshape

Subgroups and Subgroups and common namescommon names

Ascoviridae Ds DNA Allantoid None -

Baculoviridae Ds DNA Bacilliform Polyhedral NPV

Cigar- shaped capsules

GV

Calciviridae ss RNA Isometric None -

Iridoviridae ss DNA Isometric None Iridscent

Nodaviridae ss RNA Isometric None -

Parvoviridae ss DNA Isometric None -

Picornaviridae ss RNA Isometric None -

Polydnaviridae ssDNA Ovoid None -

Poxviridae Ds DNA Ovoid or brick shaped

Spheroid Entomopox viruses

Reoviridae Ds DNA Isometric Polyhedral Cytoplasmic polyhedrosis

Rabhdoviridae ss RNA Helical None -

BaculovirusesBaculoviruses► Rod-shaped, double stranded DNA genomes of 88-Rod-shaped, double stranded DNA genomes of 88-

153 kbp 153 kbp ► Causes infection by mouthCauses infection by mouth► Replicate rapidly & causes extensive cell and tissue Replicate rapidly & causes extensive cell and tissue

destruction in host celldestruction in host cell► Mostly found in nucleus of host cellsMostly found in nucleus of host cells► Virions are contained within proteinaceous particles Virions are contained within proteinaceous particles

called occlusion bodiescalled occlusion bodies► Can be mass produced by single cottage industriesCan be mass produced by single cottage industries► Highly host specific and have been isolated only from Highly host specific and have been isolated only from

invertebratesinvertebrates► Primarily pathogens of insects of order Lepidoptera Primarily pathogens of insects of order Lepidoptera

but can also infect Hymenoptera, Diptera, Coleoptera but can also infect Hymenoptera, Diptera, Coleoptera and Trichopteraand Trichoptera

► Apprx. 60 percent of Apprx. 60 percent of 1200 known insect 1200 known insect viruses belongs to viruses belongs to family baculoviridaefamily baculoviridae

► Baculovirus infection Baculovirus infection described in 700 described in 700 species of species of invertebratesinvertebrates

OrderOrder SpeciesSpecies

LepidopteraLepidoptera 455455

HymenopteraHymenoptera 3131

DipteraDiptera 2727

ColeopteraColeoptera 55

NeuropteraNeuroptera 22

TrichopteraTrichoptera 11

ThysanopteraThysanoptera 11

SphanopteraSphanoptera 11

Baculovirus

NPVMany virions within occlusion body called polyhedra, occurs in nucleus

GVOne or two virions within occlusion

body called granules, occurs in nuclear- cytoplasmic milieu after

rupture of nuclear membrane

SNPV Single packaging

of nucleocapsid in virion

MNPVmultiple packaging

of nucleocapsid in virion

Mode of Action

Table:4 Efficacy of Table:4 Efficacy of Baculoviruses against Baculoviruses against

insect pestsinsect pestsVirus Dose Pest Mortality (%)

Reference

HzNPV 100-250 LE/ha

Helicoverpa zea

90- 96 Dhaliwal et al., 2007

SINPV 375 LE/ha Spodoptera litura

95.00 Arora et al., 2003

HaNPV 1 X 108 OB’s Helicoverpa armigera

90.60 Snegapriya and Manjula, 2008

AgNPV 50 LE/ha Anticarsia gemmatalis

80.00 Dhaliwal et al., 2007

SNPV - Helicoverpa armigera

Effective control

Hu et al., 2003

SfNPV 2.5X 1011 OB’s

Spodoptera frugiperda

Effective control

Dhaliwal et al., 2007

Genetic Genetic ImprovementImprovement

►To combine pathogenecity of virus with To combine pathogenecity of virus with insecticidal action of a toxin, hormone insecticidal action of a toxin, hormone or enzymeor enzyme

►To improve production, modifying host To improve production, modifying host range & enhancing utility range & enhancing utility

►To reduce the time from infection with To reduce the time from infection with recombinant virus to death of infect recombinant virus to death of infect such that feeding damage is below such that feeding damage is below economic threshold economic threshold

Recombinant DNA Technology

Viral Genomic DNA Plasmid

Cultured insect cells

b

A B

a

Foreign gene

b

a b

Viral DNA

Transfer vector

Homologous recombination

Allelic replacement

Screening by Plaque assay selection of recombinant virus

ExamplesExamples► Buthus eupeus Buthus eupeus insect toxin- 1 (BeIt) is an insect insect toxin- 1 (BeIt) is an insect

specific paralytic neurotoxin isolated from scorpion specific paralytic neurotoxin isolated from scorpion Buthus eupeus, Buthus eupeus, was inserted into AcMNPV was inserted into AcMNPV ((Autographa californica Autographa californica multiple nuclear multiple nuclear polyhedrosis virus) genome under control of polyhedrosis virus) genome under control of polyhedrin gene promoterpolyhedrin gene promoter

► Juvenile hormone esterase (JHE) gene from tobacco Juvenile hormone esterase (JHE) gene from tobacco hornworm, hornworm, Heliothis virescensHeliothis virescens genome into AcMNPV genome into AcMNPV genome. In late instar lepidopterous larvae, genome. In late instar lepidopterous larvae, juvenile hormone is inactivated by an increase in juvenile hormone is inactivated by an increase in JHE level, this reduction in JH titers initiates JHE level, this reduction in JH titers initiates metamorphosis to the pupal stage and to a metamorphosis to the pupal stage and to a cessation of feedingcessation of feeding

Kaushik, 2008

Field Stability and Field Stability and PersistencePersistence

► Highly susceptible to damage by desiccation Highly susceptible to damage by desiccation and by exposure to sunlight or UV radiationsand by exposure to sunlight or UV radiations

► Additives like Charcoal, egg albumin, Additives like Charcoal, egg albumin, molasses, optical brighteners and sugarmolasses, optical brighteners and sugar

► Addition of crude sugar (15%) to HaNPV Addition of crude sugar (15%) to HaNPV spray fluid increased persistence of virus spray fluid increased persistence of virus both under natural sunlight and shadeboth under natural sunlight and shade

► Brighteners reduces the LCBrighteners reduces the LC5050 of gypsy moth of gypsy moth Lymantia disparLymantia dispar NPV by 800- 1300 fold NPV by 800- 1300 fold

► Evening sprayEvening spray

Baculoviruses are Baculoviruses are safesafe

►Only found in insects (mainly Only found in insects (mainly lepidopterean species)lepidopterean species)

►Narrow host range, high selectivityNarrow host range, high selectivity►No production of metabolites or toxinsNo production of metabolites or toxins►Baculoviruses are safe and cause no Baculoviruses are safe and cause no

hazards to human healthhazards to human health

ProtozoansProtozoans► More than 1000 species pathogenic to More than 1000 species pathogenic to

insectsinsects► Chronic nature of infection so limited Chronic nature of infection so limited

efficiencyefficiency► Few are Highly virulent or fast acting so Few are Highly virulent or fast acting so

more appropriate for long term control more appropriate for long term control programmes with high economic injury programmes with high economic injury levellevel

► Sarcomastigophora, Apicomplexa, Sarcomastigophora, Apicomplexa, Microspora and CiliophoraMicrospora and Ciliophora

Table:Table:5 Protozoans 5 Protozoans considered for control of considered for control of

insect pestsinsect pestsParasiteParasite HostHost

MicrosporidiansMicrosporidians

Nosema acridophagous, N. Nosema acridophagous, N. cuneatum, N. locustaecuneatum, N. locustae

GrasshoppersGrasshoppers

N. algeraeN. algerae Anopheles albimanus, Culex Anopheles albimanus, Culex tritaeniorhynchustritaeniorhynchus

N. fumifueranaeN. fumifueranae Spruce budwormSpruce budworm

N. heliothidisN. heliothidis Helicoverpa zeaHelicoverpa zea

N. pyraustaN. pyrausta Ostrinia nubialisOstrinia nubialis

N. whiteiN. whitei Tribolium castaneumTribolium castaneum

N. N. spp.spp. Helicoverpa armigera, Spodoptera Helicoverpa armigera, Spodoptera litura litura

Vairimorpha necatrixVairimorpha necatrix Agrotis ipsilon, Helicoverpa zeaAgrotis ipsilon, Helicoverpa zea

Contd….Contd….ParasiteParasite HostHost

Septate gregarines

Gregarina garnhani Schistocera gregaria

G. polymorpha Tenebrio molitor

Aseptate gregarines

Ascogregarina culicis, A. geniculati

Aedes aegypti

Neogregarines

Mattesia trogodermae Trogoderma granarium

Farinocystis tribolii Tribolium castaneum

Mode of ActionMode of Action► Similar to that of virusesSimilar to that of viruses► N. N. spp. normally invade fat body and spp. normally invade fat body and

pericardiumpericardium► Pathogenecity expression:Pathogenecity expression: Increased Increased

mortality rates, reduced fecundity, delayed mortality rates, reduced fecundity, delayed development, decreased activity and reduced development, decreased activity and reduced food consumptionfood consumption

► Cytopathological effects:Cytopathological effects: Nuclear and cellular Nuclear and cellular hypertrophy, extensive alteration of hypertrophy, extensive alteration of cytoplasmic organelles like ER, Mitochondria, cytoplasmic organelles like ER, Mitochondria, ribosome bodies, protein granules and ribosome bodies, protein granules and vacuolesvacuoles

Metarhizium anisopliae Beauveria bassiana infection of Clover Worm

Beauveria bassiana infection of worm within woody substrate

Fungi

Table:6 Entomopathogens used Table:6 Entomopathogens used for the control of pestsfor the control of pests

ProductProduct FungusFungus TargetTarget

Mycotol, Vertalec Verticillium lecanii Whitefly, thrips and aphids

Meta guard, Metarhizium anisopliae Termites

Biogreen Metarhizium anisopliae Locusts

Bio-Path Metarhizium anisopliae Cockroaches

Bio-Blast Metarhizium anisopliae Termites

Cobicant Metarhizium anisopliae Sugarcane spittle bug

Bio-Cane Metarhizium anisopliae Cane grubs

Green Muscle Metarhizium anisopliae Locusts, grasshoppers

Conidia Beauveria bassiana Coffee berry borer

Cornguard Beauveria bassiana European corn borer

Naturalis- L Beauveria bassiana Cotton pests

Mycotrol GH Beauveria bassiana Locusts, grasshoppers

Mycotrol WH and Botanigard

Beauveria bassiana Whitefly, aphids, thrips

PFR- 97, Pae- Sin Paecilomyces fumosoroseus

Whitefly

Entomopathogenic fungi -in Insect Control

Entomopathogenic fungi -in Insect Control

Tea Mites

Rice bugs

Helicoverpa Beauveria infected Helicoverpa

Paecilomyces infected tea mites

Metarhizium infected rice bugs

The Pests which are difficult to control by Pesticides can be controlled by Biopesticides

Mode of action of Mode of action of Entomopathogenic fungiEntomopathogenic fungi

Table: 7 Table: 7 Selected Selected metabolites of importantmetabolites of important Entomopathogenic fungiEntomopathogenic fungi

Pathogen Metabolite

Metarhizium anisopliae Destruxins (>27 types), cytochalasin

Beauveria bassiana Bassianin, beauvericin, bassianolide, tenellin

Beauveria brogniartii Oosporein

Paecilomyces fumosoroseus Beauvericin, beauverolies, pyridine-2,6-dicarboxylic acid

Verticillium lecanii Dipcolonic acid, hydroxycarboxylic acid,

vertilecannins, bassianolide

Tolypocladium spp. Cyclosporin, efrapeptins (5 types)

Hirustella thompsonii Hirsutellin A, hirsutellin B, phomalatone

► Destruxins :Destruxins : cyclic peptides, biological activity cyclic peptides, biological activity includes disruption of calcium balance in cells and includes disruption of calcium balance in cells and inhibition of vacuolar ATPasesinhibition of vacuolar ATPases

► Beauvericin:Beauvericin: hexadepsipeptide produced by hexadepsipeptide produced by Beauveria bassiana, Paecilomyces fumosoroseus Beauveria bassiana, Paecilomyces fumosoroseus and Fusariumand Fusarium spp. It shows antibiotic activity spp. It shows antibiotic activity against several species of bacteria and moderate against several species of bacteria and moderate insecticidal activityinsecticidal activity

► Bassianolide:Bassianolide: Lethal at high doses but induce Lethal at high doses but induce atonical symptoms at low doses in silkwormatonical symptoms at low doses in silkworm

► Bassianin and Tenellin:Bassianin and Tenellin: non-peptide toxins non-peptide toxins inhibits erythrocyte membrane ATPasesinhibits erythrocyte membrane ATPases

► Hirsutellin:Hirsutellin: Antigenic, thermostable protein. Antigenic, thermostable protein. Hirsutellin A Hirsutellin A is highly toxic to larvae of wax is highly toxic to larvae of wax moth and mosquitoesmoth and mosquitoes

► Efrapeptins:Efrapeptins: produced byproduced by Tolypocladium Tolypocladium spp.,spp., iinsecticidal and miticidal activity, limited nsecticidal and miticidal activity, limited antimicrobial activityantimicrobial activity

Factors influencing Factors influencing fungal efficacyfungal efficacy

►The PathogenThe Pathogen►The Insect hostThe Insect host►The EnvironmentThe Environment

The PathogenThe Pathogen► Virulent strain must be compatible with the Virulent strain must be compatible with the

hosthost► Spore density must be highSpore density must be high► Virulent strain must have low LDVirulent strain must have low LD50 50 & LT& LT5050

► Ecologically fit strains Ecologically fit strains persists well in fieldpersists well in fieldmore tolerant to UV radiationmore tolerant to UV radiationresist desiccation, microbial attackresist desiccation, microbial attackhave sufficient endogenous reserves to have sufficient endogenous reserves to survive adverse conditions survive adverse conditions

Insect hostInsect host► Stress Stress

Starved Starved Plutella xylostella Plutella xylostella larvae more larvae more susceptible than fed larvae tosusceptible than fed larvae to Paecilomyces Paecilomyces fumosoroseus fumosoroseus (Altre and Vandenberg, 2001)(Altre and Vandenberg, 2001)

► Developmental stage Developmental stage ► Insect densityInsect density► Insect behaviour (foraging & grooming)Insect behaviour (foraging & grooming)

Conidia of Conidia of M. anisopliae M. anisopliae are spread among are spread among individual termites by groomingindividual termites by groomingForaging coccinellids transfer conidia from Foraging coccinellids transfer conidia from sporulating cadavers to healthy aphids sporulating cadavers to healthy aphids inducing significant mortalities in aphid inducing significant mortalities in aphid populationpopulation

EnvironmentEnvironment►Solar radiations Solar radiations ►TemperatureTemperature►Relative humidityRelative humidity►RainfallRainfall►Host plantHost plant

Table:8 Efficacy of Fungi Table:8 Efficacy of Fungi against pestsagainst pests FungusFungus ConcentrationConcentration

(conidia/ ml)(conidia/ ml)Pests (Crop)Pests (Crop) Mortality Mortality

(%)(%)ReferenceReference

Beauveria bassiana 1 X 108 Lygus lineeolaris 77.47 Sabbahi et al., 2008

1 X 108 Anthonomus signatus 60.35

1 X 108 Otiorhynchus ovatus 54.50

1 X 1010 Holotrichia consanguinea

56.67 Jat and Choudhary, 2006

5 X 109 Holotrichia consanguinea

53.33

1 X 107 Varroa destructor 100.00 Meikle et al., 2006

Metarhizium anisopliae

1 X 107 Varroa destructor 75.00 Meikle et al., 2006

Beauveria bassiana 4 X 1012 to 5 X 1012

Nilaparvata lugens 63- 98 Dhaliwal et al., 2007

2 X 1012 Helicoverpa armigera 100.00 Gulati et al., 2008

2X 1012 Spodoptera litura 100.00 Gulati et al., 2008

1X 109 Pieris brassicae 50.00 Gulati et al., 2008

Nomurea rileyi 1 X 108 Helicoverpa armigera 82.10 Snegapriya and Manjula, 2008

1 X 109 Helicoverpa armigera 70.00 Manjula and krishnamurthy, 2005

1 X 109 Spodoptera litura 53.40 Manjula and krishnamurthy, 2005

Crystal

Sporulated culture

Bacillus thuringiensisBacillus thuringiensis (Bt) (Bt)

Bacteria

Insecticidal toxin of Bacillus thuringiensis B. thuringiensis is an aerobic spore-forming

bacterium which produces a toxin (Bt toxin or Cry) that kills certain insects

The Bt toxin or Cry is produced when the bacteria sporulates and is present in the parasporal crystal

Several different strains and subspecies of B. thuringiensis exist and produce different toxins that kill specific insects

They have no toxicity to human & there is no withholding period on produce sprayed with Bt

Table:9 Some properties of the insecticidal toxins from various strains of B. thuringiensisStrain/subsp. Protein size Target

InsectsCry #

berliner 130-140 kDa Lepidoptera CryI (Cry1Aa)

kurstaki KTP, HD1

130-140 kDa Lepidoptera CryI (Cry1Ab)

entomocidus 6.01

130-140 kDa Lepidoptera CryI (Cry1Ba)

aizawai 7.29 130-140 kDa Lepidoptera CryI (Cry1Ca)

aizawai IC 1 135 kDa Lepidoptera, Diptera

CryII (Cry1Da)

kurstaki HD-1 71 kDa Lepidoptera, Diptera

CryII (Cry2Ab)

tenebrionis (sd) 66-73 kDa Coleoptera CryIII (Cry3Aa)

morrisoni PG14 125-145 kDa Diptera CryIV (Cry4Aa)

israelensis 68 kDa Diptera CryIV (Cry4Ba)

Cry protein: mode of action The Cry protein is made as an inactive protoxin Conversion of the protoxin (e.g., 130 kDa) into the

active toxin (e.g., 68 kDa) requires the combination of a slightly alkaline pH (7.5-8) and the action of a specific protease(s) found in the insect gut

The active toxin binds to protein receptors on the insect gut epithelial cell membrane

The toxin forms an ion channel between the cell cytoplasm and the external environment, leading to loss of cellular ATP and insect death

Bt strain Trade name Uses

Bt var. aizurai Florback, Centari Diamondback moth

Bt var. galleriae Certan Wax moth larvae in honey combs

Bt var. israelensis Bactimos, Bactis, Thurimos, Vectobac

Larvae of mosqitoes and balckflies

Bt var. kurstaki Bt, Biobit, Dipel, Delfin, Javelin

Lepidopterous larvae

Bt var. sandiego Diterra, M- one plus

Beetles and weevils

Bt var. thuringenesis Muscabac, Thuricide

Flies, Lepidopterous larvae

Table:10Table:10 Bt based commercially available pesticides

Mechanism of Resistance Lower level of toxin activation

Bt resistant strain of Plodia interpunctella displayed slower processing and activation of Cry 1 protoxinsHeliothis virescens exhibited slow activation as well as faster degradation of toxin by midgut extracts

Reduced binding to midgut membraneP. interpunctella was found to highly resistant to Cry 1Aa, Cry 1Ab and Cry 1Ac but not to Cry 1B, Cry 1C and Cry 1D.

How to prevent it? Production of hybrid Bt toxins Stacking of Bt toxin genes Use of Bt toxins in combination with other

insecticidal proteins such as chitinase and Cyt1A

In plants, the planting of crop buffer zones with non-genetically engineered Bt plants to maintain an insect susceptible population

Bt and Human Health Risks The toxicology pathway

– Hazard is ubiquitous – Exposure (contact) is not unusual – Doses are low (below threshold for response) Results of mammalian, human studies – No effects at doses > 5,000 mg/kg Cry proteins Contrast with other insecticides – Response follows the dose

Registered MicrobialActive Ingredients Agrobacterium radiobacter Bacillus thuringiensis subsp. kurstaki Bacillus thuringiensis subsp. Israelensis Bacillus thuringiensis subsp. tenebrionis Colletotrichum gloeosporioides f.sp. malvae Cydia pomonella Granulovirus Chondrostereum purpureum Strain HQ1

Gypsy Moth Nucleopolyhedrovirus (NPV) Red-Headed Sawfly NPV HaNPV Pseudozyma flocculosa Streptomyces griseoviridis Strain K61 Ophiostoma piliferum(pending) Beauveria bassiana Metarhizium anisoplia Verticillium lecanii Nomurea rileyi

Safety testing of microbials

Necessary to know what are the hazards infection of man, livestock, useful animals and plantsPoisoning, allergy, carcinogenesis by toxins

Routes of hazards oral (by food)RespirationParenterel in woundsDermal (through skin)Might occur during production, packaging and storage of pathogens, application to crops, operations during post- harvest crop storage, consumption of treated crop & by environmental pollution

3- tier testingTier I : Includes acute oral, inhalation, intraperitoneal, dermal and ocular application plus allergenicity tests and mutagenecity screensTier II: Quantification of the effects and expanded mutagenecity testsTier III: Tetratogenecity and long term tests

Microbials are non-toxic to man and vertebrates because digestion of proteins is at low ph. Stomach enzyme pepsin (ph=2) degrades the endotoxin into atoxic compound

Table:11 Summary of desirable characteristics required by microbial pesticidesCharacteristic Bacteria Fungi Viruses Protozoa

Time to kill Good Poor Poor Poor

Easy to apply Yes Yes Yes Yes

Storage Characteristics

Good Poor Good Poor

Environmental stability

Poor Poor Poor Poor

Safe to non target organisms

Yes Yes Yes Yes

Easy to produce Yes Yes Poor Poor

BotanicalsBotanicals

Allium cepa

Chrysanthemum sp. Annona squamosa Tagetes erecta

Ricinus communis Ipomoea fistulosa

► Pesticides derived from plants Pesticides derived from plants ► Generally act in one of two ways: Generally act in one of two ways:

contact poisoncontact poison

stomach poisonstomach poison► About 2,50,000 plant species evaluatedAbout 2,50,000 plant species evaluated► 2121 useful in pest management2121 useful in pest management

1005 exhibited insecticidal activity1005 exhibited insecticidal activity

384 antifeedants384 antifeedants

297 repellents297 repellents

27 attractants27 attractants

31 growth inhibiting properties31 growth inhibiting properties

Purohit and Vyas, 2004

Table:12Table:12 Characteristics of major Characteristics of major traditional botanicalstraditional botanicals

Botanical insecticide

Source plant (s) Mode of action Toxicity Uses

Pyrethrins Flowers of pyrethrum daisy, Tanacetum

(Chrysanthemum) cinerariaefolium

Interferes with Na & k ion movement in

nerve axons

Mammalian oral

LD50 >1000, some allergic reactions can

occur

On pests and humans to control fleas, ticks ,

lice Breaks down rapidly

Rotenone Roots of Derris, Lonchocarpus, other

tropical legumes

Disrupts energy metabolism in mitochondria

Oral LD50 =25-3000

Dermal>1000

In gardens& orchards against many insects

especially beetles. Persists effectively for 4-5 days or more. Use

as a fish poison

Sabadilla Seeds of tropical lily Schoenocaulon officinale and european Veratrum

album

Interferes with Na & k ion movement in

nerve axons. Irritates skin and

mucous membranes, potent inducer of sneezing

Oral LD50 near 4000

In vegetables and fruits against bugs and citrus

thrips. Breaks down rapidly

Ryania Wood stems of Ryania speciosa

Activate Ca++ ion release channels

and causes paralysis in

muscles of insects and vertebrates

Oral LD50 near 1000 Dermal

near 4000

In fields &fruit crops against caterpilllars

&thrips. Often combine with rotenone &

pyrethrins in commercial mixtures

for garden use

Nicotine Tobacco, Nicotiana sp., Duboisia, Anabasis, Asclepis, Equistem,

Lycopodium

Mimics acetylcholine & overstimulates

receptor cells to cause

convulsions & paralysis

Oral LD50= 3-

188 Dermal near 50

Very toxic to

humans

Mostly in greenhouses &

gardens. Nicotine

fumigations target aphids, thrips &mites

Neem Leaves, bark, seeds of neem (Azadirachta indica)

& chinaberry (Melia azedarach )

Biochemical nature of feeding

deterrence, repellance,

growth regulation

effects are not well described

Oral LD50 > 13000

Use medicinally in humans. On

many crops & landscape

plants especially

against soft bodied&

secondary pests. Very

short persistence on treated plants

Limonene/

Linalool

Citrus oils Causes spontaneous stimulation of

sensory nerves, biochemical

mode of action

Limonene oral LD50

>5000Dermal>3500

Mostly in pet shampoos, dip & sprays to kill fleas & ticks.

Very short persistence on treated plants

Source: Weinzierl (2000)

Mode of action of BotanicalsMode of action of Botanicals Ovipositional deterrentOvipositional deterrent► affects the egg laying and egg hatchingaffects the egg laying and egg hatching► may be due to strong odour of product or presence of may be due to strong odour of product or presence of

substance which causes malfunctioning of ovariole in substance which causes malfunctioning of ovariole in females. eg. females. eg. Pongamia pinnataPongamia pinnata, , Annona squamosaAnnona squamosa

OvicidalOvicidal► kill eggs and disrupts embryonic development so kill eggs and disrupts embryonic development so

prevents hatching of eggs. Eg. prevents hatching of eggs. Eg. Annona squamosa, Annona squamosa, Parthenium Parthenium sp.sp.

Attractants eg. Attractants eg. RepellentsRepellents eg. Fennel ( eg. Fennel (Foeniculum vulgareFoeniculum vulgare), ),

Eucalyptus globulus, Moringa oleifera, Allium cepa, Eucalyptus globulus, Moringa oleifera, Allium cepa, MenthaMentha

Feeding deterrents/ AntifeedantsFeeding deterrents/ Antifeedants► Gustatory substances which causes the pest to stop Gustatory substances which causes the pest to stop

feeding and starve to death or causes cessation of feeding and starve to death or causes cessation of feeding. Eg. feeding. Eg. Melia azedarach, Melia azedarach, Neem, Garlic, Datura Neem, Garlic, Datura

Contd….Contd…. Antigonadal agentsAntigonadal agents ► Vapours of oil of Vapours of oil of Acorus calamusAcorus calamus reported to inhibit reported to inhibit

the development of ovaries of a no. of stored grain the development of ovaries of a no. of stored grain pests pests

► In male insects it showed sperm malformation and In male insects it showed sperm malformation and agglutinationagglutination

Insect growth regulators Insect growth regulators eg. eg. Lantana Lantana sp., sp., Pongamia Pongamia pinnatapinnata

Physiological effectsPhysiological effects► slow necrosis of mid gut epithelial cellsslow necrosis of mid gut epithelial cells► reduction in size and no. of cellsreduction in size and no. of cells► Malformation of circular and longitudinal muscles or Malformation of circular and longitudinal muscles or

welling of organelles when taken as stomach poisonwelling of organelles when taken as stomach poison NeurotoxinNeurotoxin

Which type of plants Which type of plants should we use?should we use?

The plant should be a perennialThe plant should be a perennial It should have a wide distribution & be present It should have a wide distribution & be present

in large numbers in nature otherwise it should in large numbers in nature otherwise it should be possible to grow it by agricultural practices.be possible to grow it by agricultural practices.

The plant parts used should be removable: The plant parts used should be removable: leaves, flowers or fruitleaves, flowers or fruit

Harvesting should not mean destruction of the Harvesting should not mean destruction of the plantplant

Plants should require small space, reduced Plants should require small space, reduced management, little water and fertilizationmanagement, little water and fertilization

Plant should not otherwise have a high Plant should not otherwise have a high economic valueeconomic value

The active ingredient should be effective at The active ingredient should be effective at low rateslow rates

Table:13Table:13 Important plants with Important plants with pesticidal activitypesticidal activity

Common name

Scientific name Plant parts used

Active principle

Custard apple

Annona squamosa Leaves and bark Annonin, squamocin

Pongam Pongamia glabra Leaves, fruits, seeds, oil roots and flowers

Pongamol, Pongapin, pongone, karanjanin

Eucalyptus Eucalyptus globulus Leaf and oil Camphene, limonene, linalool, α- terpienol

Moringa Moringa olefifera Leaves, flowers Moringyne

Clerodenderon

Clerodenderon indicum

Leaves Trans- decalin, clerodin

Ipomoea Ipomoea fistulosa Leaves, flowers and whole plant

Ipomomin, isoergin, ergine, ipalbdinium

Murraya Murraya koenigii Leaves and bark Murraxonin, murrayanone

Jatropha Jatropha curcas Leaves, seed, seed cake, oil

Jatrophin, curcusone, jatrophol

Common name

Scientific name Plant parts used Active principle

Datura Datura strmonium Leaves, fruits, dried seeds, roots

Atropine, hyoscyamine

Tobacco Nicotiana tabacum Leaves, whole plant Nicotine, nornicotine, anabasine

Sweet flag Acorus calamus Rhizomes Calamol, α asarone, β asarone

Lantana Lantana camera Leaves, whole plant Lantonolic acid, lantic acid

Indian Aloe Aloe vera Leaves, rhizomes Aloesin, aloin

Calotopis Calotropis gigantea Leaves, roots Calatropin, calatoxin

Mint Mentha spicata Leaves, flowers, whole plant, oil

Menthole, limonene, menthone

Ocimum Ocimum sanctum, O. basilicium

Leaves, stems, whole plants, oil

Juvocimene- I, II, ocimin

Onion Allium cepa Bulb Oleic acid, cepocode- D, α and β tocopherols

Common name

Scientific name Plant parts used Active principle

Garlic Allium sativum Leaves, flowers, whole plant, bulbs

Allicin, diallyl sulphide

Chilli Capsicum annum Leaves and fruits Capsacin

Marigold Tegetes erecta Leaves, flowers, roots

Mycene, tagetone. allopatulein

Lemon grass

Cymbopogon marginatus

Leaves and roots Cymbopogon, Cymbopogonal

Turmeric Curcuma longa Rhizomes Curcumol, curcumin

Ginger Zingiber officinali Rhizomes Gingerols, arcurcumene

Khejiri Prosopis julifora Leaves and seeds Juliprosopine, prosopidione, juliflorinine

Ardusa Ailanthus excelsa Leaves Ailanthone

Castor Ricinus communis Leaves and oil Ricin, ricinnie

Source: Dodia et al. (2008)

Pest resistance to Pest resistance to phytochemicalsphytochemicals

►Neem tree itself is attacked by about Neem tree itself is attacked by about 60 species of insects besides mites, 60 species of insects besides mites, nematodes and 16 phytopathogens nematodes and 16 phytopathogens like like Aonidiella orientalis, Pulvinaria Aonidiella orientalis, Pulvinaria maxima maxima etcetc

►Some resistance to pyrethrins has Some resistance to pyrethrins has been reported among a few been reported among a few agricultural pests, particularly those agricultural pests, particularly those with resistance to organochlorines, with resistance to organochlorines, orgaophosphates and carbamatesorgaophosphates and carbamates

Table:14 Efficacy of botanicals Table:14 Efficacy of botanicals against non insect pestsagainst non insect pests

Plant material Activity of material

Against Disease/ organism

Reference

Leaf extract of Datura

Inhibits mycelial growth

Aspergilllus flavus Satish et al., 2002


Die back of chilli Gehlot, 2005

Fungicidal activity

Paddy diseases Krishnappa et al., 2005

Garlic bulb extract Fungicidal activity

Mustard white rust powdery mildew, Club rot of sarson

Chattopadhayet al., 2005

Ethanol extract of garlic bulb


Root rot & web blight of french bean

Sharma and Gupta, 2003

Garlic, Neem, Onion, Datura, Tulsi, Mint

Antifungal activity

Alternaria of Senna Tetarwal and Rai, 2007

Onion, Ginger, Tulsi, Lantana

Antifungal activity

Penicillium expansum rot on apples

Singh and Sumbali, 2007

Plant material Activity of material Against Disease/ organism Reference

Jatropha extract - Cowpea aphid born mosaic virus

Patel, 1999

Onion, Garlic, Tulsi, Lantana

- Cowpea aphid born mosaic virus

Patel, 1999

Onion, Neem, Turmeric, Ginger

Antibacterial activity

Black gram leaf crinkle virus Thirumalaisang and Rathi, 2007

Garlic, Amaltas, Anola, Castor, Peepal, Marigold, Jatropha, Jamun,


Soft rot of radish Raju et al., 2007

Essential oils of aguaribay, anden thyme. Pepeeine, camoline and pennyroyal


Paenibacillus larvae Fuselli et al., 2006

Ocimum basilicum, Lavandula officinalis

repellent, toxic and ovipositional deterrent

Tetranychus urticae Refaat et al. (2002

Pongamia pinnata seed extract

Acaricidal activity Tetranychus urticae Monikaet al., 2009

Rotenone Varroa destructor Eguaras et al., 2005

Some medicinal plantsSome medicinal plants► Alangium salvifolium Alangium salvifolium (L.f.) Wang.(L.f.) Wang. Local name: Ooduga chettuLocal name: Ooduga chettu Medicinal uses: Medicinal uses: fruits are used as antiometicfruits are used as antiometic► Annona squamosaAnnona squamosa Linn.Linn. Local name: SethafalamLocal name: Sethafalam Medicinal uses: Medicinal uses: leaf paste is applied over joints to get relief leaf paste is applied over joints to get relief

from pain and 5 grams of seed powder along from pain and 5 grams of seed powder along with milk taken against gastric colic with milk taken against gastric colic

► Azadirachta indicaAzadirachta indica A.Juss. A.Juss. Local name: NeemLocal name: Neem Medicinal Uses: Medicinal Uses: leaf smoke is used for the control of leaf smoke is used for the control of

mosquitoes and leaf paste is used to cure skin diseases.mosquitoes and leaf paste is used to cure skin diseases.► Ailanthus excelsaAilanthus excelsa Roxb. Roxb. Local name: Pedda vepaLocal name: Pedda vepa Medicinal uses: Medicinal uses: bark and leaf smoke is used for control of bark and leaf smoke is used for control of

mosquitoesmosquitoes

► Balanites aegyptiacaBalanites aegyptiaca (L.) Del. (L.) Del. Local name: GareLocal name: Gare Medicinal uses: Medicinal uses: small twigs are kept in the ventilators to avoid the small twigs are kept in the ventilators to avoid the

entry of microbes. Dried leaf smoke is used to control the houseflies entry of microbes. Dried leaf smoke is used to control the houseflies inside the home. Fruit pulp is taken orally to control the loose motions.inside the home. Fruit pulp is taken orally to control the loose motions.

► Bambusa arundinacea Bambusa arundinacea (Retz.) Willd.(Retz.) Willd. Local name: VeduruLocal name: Veduru Medicinal uses: Medicinal uses: stem stripes are used to bind the fractured bonesstem stripes are used to bind the fractured bones..► Calotropis procera Calotropis procera (Ait.) Aitf.(Ait.) Aitf. Local name: jelladuLocal name: jelladu Medicinal uses: Medicinal uses: leaves are pounded with caster oil and banded over leaves are pounded with caster oil and banded over

knee joints to get relief from joint painknee joints to get relief from joint pain► Eucalyptus globulusEucalyptus globulus Local name: SafedaLocal name: Safeda Medicinal uses: Medicinal uses: Externally for athlete’s foot disease, dandruff, Externally for athlete’s foot disease, dandruff,

inhalation for asthmainhalation for asthma► Ginkgo bilobaGinkgo biloba Local name: ginkgoLocal name: ginkgo Medicinal uses: Medicinal uses: Relieves asthma, treat cerebral disordersRelieves asthma, treat cerebral disorders► Vitex negundo Vitex negundo Local name: Local name: VaviliVavili Medicinal uses: Medicinal uses: Malaria, poisonous bites, leukemia, reduce blood Malaria, poisonous bites, leukemia, reduce blood

pressurepressure

Advantages of Advantages of BiopesticidesBiopesticides

Difficult for insects to develop resistance to these Difficult for insects to develop resistance to these pesticidespesticides

Safe to natural enemies and higher organisms Safe to natural enemies and higher organisms Biodegradable :Biodegradable : Rapid degradation of the active Rapid degradation of the active

ingredient make it more acceptable. ingredient make it more acceptable. In cotton residues of In cotton residues of Azadirachtin dissipated within 12 hr when applied @ 20 & Azadirachtin dissipated within 12 hr when applied @ 20 & 40 ppm concentrations40 ppm concentrations (Indumathi, 2002) (Indumathi, 2002)

Cheaper, renewable, can be handled safelyCheaper, renewable, can be handled safely Often have other uses like household insect repellents or Often have other uses like household insect repellents or

are plants with medicinal properties are plants with medicinal properties Most are compatible with insecticides and microbial Most are compatible with insecticides and microbial

agentsagents There is great demand for residue free cotton garments, There is great demand for residue free cotton garments,

fruits, vegetables and beverages, large scale utilization of fruits, vegetables and beverages, large scale utilization of botanical pesticides will certainly help us in meeting botanical pesticides will certainly help us in meeting international standards of quality and safety in these international standards of quality and safety in these productsproducts

Disadvantages ofDisadvantages of BiopesticidesBiopesticides

Slow effectSlow effect Lack persistence and wide spectrum activityLack persistence and wide spectrum activity Rapidly degraded by UV light so residual action is Rapidly degraded by UV light so residual action is

slow. slow. Half lives of pyrethrins on tomato and bell Half lives of pyrethrins on tomato and bell pepper fruits were 2 hrs or lesspepper fruits were 2 hrs or less (Antonious, 2004) (Antonious, 2004)

Effective dose is higher i. e. 30 ml/10L especially in Effective dose is higher i. e. 30 ml/10L especially in neemneem

Seasonal availability of plant products indicates the Seasonal availability of plant products indicates the need for their storageneed for their storage

Not easily available everywhereNot easily available everywhere Poor water solubility and are generally not Poor water solubility and are generally not

systemic in naturesystemic in nature All products applied followed by growers have not All products applied followed by growers have not

been scientifically verifiedbeen scientifically verified

1. Inherently less harmful than conventional pesticides

2. Suppress, rather than eliminate, a pest population, so leaves the vulnerable population to natural enemies

3. Effective and often quickly biodegradable and present no residue problems

4. Mostly self perpetuating

5. Safe for non target organisms and human

Conclusion

Future prospective

Ecological studies on dynamics of diseases in insect populations are necessary

Efforts should be made to minimize the loss of infectivity of certain pathogens due to photoinactiavtion

Extension work needs to be geared up among the farming community to make them aware about the use and benefits of biopesticides

Biotechnological approaches could be useful for obtaining bioactive products on large scale

use of biopesticides

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