Size and flight ability of Telenomus remus parasitoids reared on eggs of the factitious host Corcyra cephalonica

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REVISTA

BRASILEIRA

DE

Entomologia

AJournalonInsectDiversityandEvolution

w w w . r b e n t o m o l o g i a . c o m

Biological

Control

and

Crop

Protection

Size

and

ﬂight

ability

of

Telenomus

remus

parasitoids

reared

on

eggs

of

the

factitious

host

Corcyra

cephalonica

Aline

Pomari-Fernandes

a

_,

_Adeney

_de

_Freitas

_Bueno

b,∗

_,

_Sérgio

_Antonio

_De

_Bortoli

c

a_Universidade_Federal_da_Fronteira_Sul,_Laranjeiras_do_Sul,_PR,_Brazil

b_Empresa_Brasileira_de_Pesquisa_{Agropecuária,}_Embrapa_Soja,_Londrina,_PR,_Brazil

c_Faculdade_de_Ciências_Agrárias_de_Jaboticabal,_Universidade_Estadual_Paulista,_Jaboticabal,_SP,_Brazil

a

r

t

i

c

l

e

i

n

f

o

Articlehistory:

Received19October2015 Accepted12February2016 Availableonline4March2016 AssociateEditor:DanielR.Sosa-Gomez Keywords:

Eggparasitoid Insectmassrearing Platygastridae Naturalenemy

a

b

s

t

r

a

c

t

Intwoindependentbioassays,sizeandflightabilityofparasitoidsrearedoneggsofCorcyracephalonica for19generationsandparasitoidsrearedonanaturalhost(Spodopterafrugiperdaeggs)for250 gener-ationswerecomparedasfastqualitycontrolproceduresforinsectrearing.Thesizeofparasitoidswas examinedbymorphometricanalysisusingastereoscope.Lengthandwidthofthewings,righthind tibia,andthebodyof20individuals(malesandfemales)weremeasured.Intheanalysisofflightability, parasitoidsweredividedintothreegroups:individualsabletofly(“flyers”),individualsthatdidnotfly buthadnovisibledeformation(“walkers”),andindividualswithvisibledeformation(“deformed”).We observedthatparasitoidswerelargerwhenrearedonthenaturalhostthanonthefactitioushostfor allevaluatedmorphologicalcharacters.However,therewasnosignificantdifferencebetweenthe treat-mentsregardingthenumberof“flyers”,“walkers”or“deformed”parasitoids.Thisindicatesthateven thoughtherearingofT.remusonafactitioushostaffectsparasitoidsize,itdoesnotnecessarilyaffectits flightabilityandthereforesuggeststhatC.cephalonicaissuitableasafactitioushostformassrearingof T.remus.Otherbiologicalparametersstillneedtobeevaluated,suchashostfindingability,parasitism capacity,andparasitoidfieldefficacyinordertoprovideamorecompletepictureoftheeffectscaused byahostchange.However,becausefastlaboratorytestsareneededinrearingfacilities,theoneusedin thisstudymightbeusefultorapidlyassessparasitoidquality.

Introduction

Telenomusremus(Nixon,1937)(Hymenoptera,Platygastridae) isan eggparasitoidofvariousLepidopteraspecies (Cave, 2000,

Pomarietal.,2012),currentlyonlyrearedonasmallscaledueto

theinherentdifﬁcultiesofrearingitonitsnaturalhost,Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera, Noctuidae) (

Pomari-Fernandesetal.,2014).Spodopterafrugiperdarearingistoo

time-andresource-consuming(Perkins,1979),mainlybecauseoflarval cannibalism,whichrequirestherearingoflarvaeinindividualvials todecreasepre-imaginalmortality(Chapmanetal.,2000).A possi-blealternativeisrearingtheparasitoidonafactitioushost.Natural enemyrearingonfactitioushostsisadeterminingfactorforthe successofmanybiologicalcontrolprogramsbecauseitreduces pro-ductioncostsandincreasestheviabilityforthelarge-scaleuseof thebiocontrolagent(Parra,1997).

∗ Correspondingauthor.

E-mail:adeney.bueno@embrapa.br(A.deFreitasBueno).

It is crucialthat laboratory-rearedinsects remaincapableof controllingtargetpestsin thefield similartobiologicalcontrol agentsfoundinnature(ClarkeandMcKenzie,1992).Thishasbeen one ofthemain goalsof insect-rearingfacilities that were cre-atedtosupplybiologicalcontrolprogramswithnaturalenemies oftargetpests.Therefore,qualitycontroloftheproducedinsectis akeyfactorforthesuccessofmostbiologicalcontrolprograms, withtheoverallqualityofthenaturalenemydefinedasits abil-itytocontroltargetpestsafteritsreleaseinthefield(Clarkeand

McKenzie,1992).However,ﬁeldevaluationcanbeexpensiveand

ineffectiveifitisnotclearlydefined.Thus,fastandeasy-to-perform laboratorytestsareoftheoreticalandpracticalinterest.Theycan giveanindicationoffieldperformanceandprobablymakeamore labor-intensivefieldevaluationunnecessary.Forexample,inorder toimproverearingoftheeggparasitoidTrichogrammapretiosum Riley,1879(Hymenoptera:Trichogrammatidae),theInternational OrganizationofBiologicalControl(IOBCGlobalWorkingGroup: QualityControlofMassRearedArthropods)recommendsthe eval-uationofsevendifferentbiologicalvariablesinthelaboratory(van

Lenteren,2003).However,Prezotti(2001)reportedthatonlythe

http://dx.doi.org/10.1016/j.rbe.2016.02.004

0085-5626/© 2016 Sociedade Brasileira de Entomologia. Published by Elsevier Editora Ltda. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

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variableslongevity,parasitismindex,andﬂightactivityneedtobe assessedtomaintainthehighqualitystandardsrequiredformass rearingofthiseggparasitoid.

Flyingandwalkingareimportantcharacteristicsforanatural enemy’sperformanceunderﬁeldconditionssincetheyaredirectly relatedtoitsforaginganddispersalcapacity(GardnerandLenteren, 1986).Itisimportanttopointoutthatthevaluesofthesetraits maychangeacrossgenerations duringmassrearing,and there-foreshouldbeclosely monitored.Thus,toensurethequalityof laboratory-producedparasitoids,itisimportanttodevelop meth-odsthatassesstheabilityofparasitoidstoﬂyandwalk.

In addition, insect morphology must be considered, which maybeinﬂuencedbyenvironmentalvariationandhostchanges

(Grenieretal.,2001).Parasitoidsizeisamorphologicalparameter

thatmightbeimpairedbyhostchoice.Therefore,thisstudyaimed toevaluatethesizeand ﬂightabilityofT.remusrearedoneggs ofthefactitious hostCorcyra cephalonica(Stainton,1866) (Lepi-doptera:Pyralidae)comparedtothoserearedoneggsofthenatural hostS.frugiperdainordertodeterminedifferencesbetweenthose parasitoids.Thisresearchgeneratedinformationthatwillhelpto improvethequalitycontroloffutureT.remusmassproductionin thelaboratoryaswellastheuseofthiseggparasitoidinextensive biocontrolprograms.

Materialandmethods

Parasitoidandhostcolonies

Corcyracephalonicaeggs,S.frugiperdaeggsandT.remusfemales usedintheexperimentscamefrominsectcolonieskeptatEmbrapa Soybean,Londrina,StateofParaná,Brazil.Spodopterafrugiperda wasoriginally collected from maize plants in Rio Verde, State ofGoiás,andhasbeenkeptinthelaboratoryforapproximately ﬁveyears.Thisspeciesisrearedunderlaboratory-controlled envi-ronmental conditions (25±2◦C temperature, 70±10% relative humidity,and14/10hphotoperiod[L/D])andfedontheartiﬁcial dietdescribedbyGreeneetal.(1976)andParra(2001).Corcyra cephalonicawassuppliedbyUNESP/Jaboticabalandhasbeenkept inthelaboratoryforapproximatelythreeyears.Corcyracephalonica isrearedonitsnaturaldiet,usingamethodologyadaptedfrom Zeller(1879)forrearingAnagastakuehniella(Lepidoptera:

Pyrali-dae)(Parra,1997).

TelenomusremuswasoriginallycollectedinEcuadorandreared attheparasitoidrearingfacilitiesofESALQ/USP(LuizdeQueiroz CollegeofAgriculture/UniversityofSãoPaulo),fromwheresome specimens were transferred to Embrapa Soybean seven years (around250generations)ago.AtEmbrapaSoybeanlaboratory,T. remuswasrearedonbothS.frugiperdaeggmassesandonunviable C.cephalonica(upto24h)eggsinordertoprovidetwodistinct colonies(rearedondifferenthosts).Ineachcolony,hosteggswere gluedonto whiteBristol board (2.5cm×5cm)and placed with eggspreviouslyparasitizedbyT.remus.Smalldropsofhoneywere addedtotheinsideofthesetubestofeedtheadultsassoonasthey emerged.Thetubeswerethenclosed,andtheeggswereallowed tobeparasitizedfor24h.Theadultsthatemergedfromtheseeggs wereusedfortrialsorcolonymaintenance.

MorphologicalcharactersofTelenomusremus

Theexperimentwascarried outin a5×2factorial random-izedblockdesign(5parasitoids×2 parasitoidgenders –female ormale)with10replicatesconsistingofoneadultthatwas mea-suredindividually.Therefore,10maleand10femaleparasitoids rearedonC.cephalonicaeggsfromfourdifferentgenerations(F1,F8, F13,andF19)wereanalyzedandcomparedwithparasitoidsreared onS.frugiperda.TelenomusremusrearedonS.frugiperdaeggsand

exposedtoparasitismonC.cephalonicaeggsformedtheF0 gen-eration.TheF1 generationwastheﬁrstgenerationofparasitoids rearedonC.cephalonicaeggs,andsuccessivelyafterwards.

Foreachreplicate(adultinsect),morphometricevaluationsof lengthandwidthoftherightanteriorwing,lengthof theright hindtibia,andbodylength(headtothetipoftheabdomen)were performed.Tomeasuremorphologicalcharacters,eachspecimen wasphotographedinastereoscopicmicroscope(LeicaApplication Suite,Version1.6.0).Imageswereusedformorphometricanalysis withthesoftwareImageJ(Version1.47).

FlightabilityofTelenomusremus

Thetrialwascarriedoutin controlledenvironmental condi-tionsinsideaBiochemicalOxygenDemand(BOD)climatechamber (ELETROLab®,modelEL212,SãoPaulo,SP,Brazil)setat70±10% humidity,temperatureof25±2◦C,and12/12hphotoperiod(L/D). Experimental design was completelyrandomized with 5 treat-ments(T.remusfromC.cephalonicaeggsoftheF1,F8,F13,andF19 generationsandT.remusfromeggsofthenaturalhost,S.frugiperda) and10replicates.Eachreplicatecontained100–150pupaeofT. remusrearedonC.cephalonica(F1,F8,F13,andF19)orS.frugiperda eggs.Aroundthetimeofemergence,thoseT.remuspupaewereput onaplasticplateof2.5cmdiameterand1cmheight,whichwas placedonthebottomofeachreplicate.Thisprotocolwasoriginally proposedbyDuttonandBigler(1995)andadaptedinESALQ-USP

(Prezottietal.,2002),asbrieﬂydescribedinthefollowing.

ReplicatesconsistedofacagemadeofaPVCcylinder(18cm highand11cmindiameter).Theinteriorofthecagewaspainted withblackinkonawhiteacryliclatexlayertofacilitateattachment. Thebottomofthecagewassealedwithflexibleblackplastic(larger thanthetubediameter)fittedtightlybyaStyrofoamdisk approxi-matelyonecentimeterthickandofthesamediameterasthetube. Afterfitting,theprotrudingportionoftheplasticwasfixedtothe tubebyelasticbands,creatingaperfectsealandpreventingthe escapeofparasitoids.Then,entomologicaladhesive(composedof polybuteneandsyntheticsilica)wasspreadoverthewallsofthe cage(3.5cmfromthebottom),toserveasatrapfor“walkers” (par-asitoidsthatwereunabletoflybutcouldwalkandhadnovisible deformation).AtransparentPetridishsprayedwithentomological adhesivewasplacedontopofthecylindertoserveasatrapfor flyingparasitoids.

The positionand the number of parasitoidsin the adhesive ring(“walkers”),inthePetridish(“ﬂyers”),and“deformed”were recordedandusedtocalculatetheirpercentagesofthetotal num-ber of emerged adults. The parasitoids considered “non-ﬂyers” wereobservedunderastereoscopetodeterminethepercentage ofindividualswithwingdeformities(“deformed”)(Prezottietal.,

2002).

Dataanalyses

Prior to ANOVA, experimental results were subjected to exploratoryanalysesto assess theassumptions of normalityof residuals (Shapiro and Wilk, 1965) and homogeneity of vari-anceofthetreatments(BurrandFoster,1972)and,ifnecessary, transformed for ANOVA. For “Deformed” parasitoids, data was transformedby√X+0.5.Thetreatmentmeanswerethen com-paredbytheTukeytestatthe5%probabilitylevel(SASInstitute,

2001).

Results

MorphologicalcharactersofTelenomusremus

Therewasnointeractionbetweenparasitoidsand genderin thefactorial analyses(Table1),andthereforeboth factorswere

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Table1

Telenomusremus:measurementsofmorphologicalcharacters(mm)whenrearedontheeggsofthenaturalhost(Spodopterafrugiperda)andthefactitioushost(Corcyra cephalonica).

Parameter Morphologicalcharacters(cm)a

Winglength Wingwidth Bodylength Righthindlength

Parasitoid S.frugiperdab _0.546_±_0.008_a _0.176_±_0.003_a _0.601_±_0.013_a _0.152_±_0.004_a C.cephalonicac_F 1 0.485±0.007b 0.152±0.003b 0.551±0.008b 0.132±0.003c C.cephalonicaF8 0.490±0.006b 0.157±0.003b 0.584±0.010ab 0.146±0.003ab C.cephalonicaF13 0.487±0.007b 0.149±0.003b 0.567±0.012ab 0.131±0.003c C.cephalonicaF19 0.476±0.007b 0.151±0.002b 0.570±0.010ab 0.140±0.003bc Gender Female 0.483±0.005B 0.155±0.002ns _0.601_±_0.007_A _0.132_±_0.002_B Male 0.510±0.006A 0.159±0.002 0.547±0.005B 0.149±0.002A Statistics CV(%) 5.81 8.17 6.80 8.18 Fhost/generation 18.85 14.13 4.71 12.61 Fgender 21.41 2.98 48.95 54.01 Fhost/generation*gender 0.10 0.19 0.60 1.35 phost/generation <0.0001 <0.0001 0.0018 <0.0001 pgender <0.0001 0.0881 <0.0001 <0.0001 phost/generation*gender 0.9829 0.9408 0.6624 0.2599

a_Means_(±SE)_followed_by_the_same_lower_case_letter_in_{host/generation}_and_capital_letters_in_gender_parameters_did_not_{statistically}_differ_(Tukey_test,_p_>_0.05)_for_each

morphologicalcharacter.

b_T._remus_reared_on_eggs_of_S._frugiperda_by_{approximately}₂₅₀_generations. c _T._remus_reared_on_eggs_of_C._cephalonica_by₁_(F

1),8(F8),13(F13),and19(F19)generations. ns _{Non-signiﬁcant.}

analyzed independently. In the parasitoids analysis,differences wereobserved in all evaluatedmorphological characters:wing length, wing width, body length, and right hind tibia length

(Table1).Overall,morphologicalmeasurements(mm)ofT.remus

hadhighervalueswhentheparasitoidwasrearedonthenatural host,S.frugiperda.Winglengthandwidthvaluesweresigniﬁcantly higherofT.remusrearedonS.frugiperdathanofparasitoidsreared onC.cephalonicaeggs(F1,F8,F13,andF19generations).Bodylength didnotdifferbetweenparasitoidsrearedoneggsofS.frugiperdaor C.cephalonicaF8,F13,andF19.Also,therighthindtibialengthwas similarbetweenparasitoidsfromS.frugiperdaandC.cephalonica

F8(Table1).Intheanalysisofthefactorgender,maleshadlonger

wingsandtibiaethanfemalesbutshorterbodylength.Incontrast, wingwidthdidnotdifferbetweenthegenders(Table1).

FlightabilityofTelenomusremus

Thetotalnumberofparasitoidsemergingfromthe100to150T. remuspupaewassimilarforthetwohosts,varyingfrom114.8(C. cephalonicaF1)to127.6(S.frugiperda)(Table2).ThenumberofT. remus“ﬂyers”rearedonS.frugiperdaeggs(102.8)didnotdifferfrom

thatofparasitoidsrearedonC.cephalonicaeggsintheF1(96.8),F8 (96.4),F13(101.9),andF19(106.3)generations(between80.33%and 84.43%“ﬂyers”,Table2).Likewise,thenumberofparasitoids with-outanyvisibledeformationthatdidnotﬂy(“walkers”)weresimilar betweentreatments.Inaddition,“deformed”parasitoidswereless than1%ineachtreatment,anddidnotdifferbetweentreatments

(Table2).

Discussion

TheobservedreductioninmorphologicalcharactersofT.remus whenswitchingfromeggofanaturaltothoseofafactitioushost mightbeassociatedwiththedifferentformsandsizesofbothhost eggs.Moreover,differenthosteggsmighthavedifferentsurfaces, chorion structures, and other egg properties during embryonic development(Cônsolietal.,1999).Thosehostfeatureswere previ-ouslypointedoutasimportantfactorsforT.remusparasitismand developmentbyBuenoetal.(2014).Thereisanimportant differ-enceinshapebetweeneggsofC.cephalonica,whichareellipsoidal (meanlength573.5mmandmeanwidth346.1mm)andeggsof S.frugiperda,whicharealmostspherical(meanlength454.9mm

Table2

Telenomusremus:ﬂightability(mean±SEnumberofparasitoidsemergedfromdifferenthosts).

Host Ga _Total_parasitoidsb _Flyersc _Walkersd _Deformede,f

S.frugiperda * 127.6±3.9ns _102.8_±_2.7ns_(80.83%) _23.9_±_2.4ns_(18.49%) _0.9_±_0.2ns_(0.68%) C.cephalonica F1 114.8±4.2 96.8±3.4(84.43%) 17.3±1.8(14.92%) 0.7±0.2(0.64%) C.cephalonica F8 116.4±2.0 96.4±1.9(82.89%) 19.7±1.7(16.86%) 0.3±0.2(0.25%) C.cephalonica F13 122.7±4.2 101.9±3.0(83.33%) 20.2±2.7(16.17%) 0.6±0.3(0.50%) C.cephalonica F19 126.9±2.4 106.3±2.3(83.84%) 20.0±1.9(15.70%) 0.6±0.2(0.47%) CV(%) 9.03 8.39 17.68 21.38 F 2.87 2.47 1.09 0.98 p 0.0336 0.0578 0.3753 0.4261

a_Generation_of_parasitoids_used_in_the_treatment_(*T._remus_was_reared_on_eggs_of_S._frugiperda_for_{approximately}₂₅₀_generations_and_on_eggs_of_C._cephalonica_for₁_(F 1),

8(F8),13(F13),and19(F19)generations).

b_Total_number_of_parasitoids_emerged_in_the_treatment_(Flyer₊_Walkers₊_Deformed).

c _Number_of_parasitoids_able_to_ﬂy,_and_its_proportion_(%)_of_the_total_number_of_parasitoids_emerged.

d _Number_of_parasitoids_that_did_not_ﬂy_but_had_no_visible_deformation,_and_its_proportion_(%)_of_the_total_number_of_parasitoids_emerged. e_Number_of_parasitoids_with_visible_deformation,_and_its_proportion_(%)_of_the_total_number_of_parasitoids_emerged.

f _Statistics_performed_on_transformed_data_by√_X₊_0.5. ns _{Non-signiﬁcant.}

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and mean width 390.2mm) (Cônsoli et al., 1999). Host size is reportedtobedirectlyrelatedtoparasitoiddimensions(Gautum, 1986).Forexample,adultsofT.remus,rearedonAgrotisspinifera (Hubner,1808) (Lepidoptera: Noctuidae)eggswere largerthan parasitoidsfromSpodopteralitura(Fabricius,1775)(Lepidoptera: Noctuidae)eggs,whicharesmaller.However,bothC.cephalonica andS.frugiperdaeggshaveasimilarvolumeofaround0.036mm3

(Cônsolietal.,1999).Thisindicatesthatthehostinﬂuenceonthe

morphologyoftheproducedparasitoidsisnotduetoeggsizealone. Forexample,differenttimespansofco-evolutionbetweenT. remusanditsvarioushostsmayhaveresultedindifferentdegrees ofadaptationtoeachspecifichostegg(Buenoetal.,2009).The studiedT.remuscolonyhasbeenrearedonS.frugiperdaeggsunder laboratoryconditionsforabout250generations,possiblyleading tobetteradaptationoftheparasitoidstraintothishostcompared withC. cephalonica,which wasreared for only 19 generations. Asaconsequence,memoryoftheoriginalhostmaybeinvolved in host-locatingability and hostacceptance and therefore may haveinfluencedtheresultsreportedhere.However,itis impor-tanttopointoutthatparasitoidsdisplayinterspecificvariationin learningrateandmemorydynamicsthatreflectsvariationinthe foragingtaskandlargelydeterminestheirfitness(Hoedjesetal., 2011).Hostpreferenceinnatetothespecies(pre-imaginal condi-tioning)mightbealteredbylearningrateandmemorydynamics asaresult ofexperiencegainedduring foragingand parasitism

(Pomari-Fernandesetal.,2015).Althoughlearningisusually

con-sideredasmoreimportantforgeneralists,itisalsoacrucialfactor forspecialist parasitoidwasps (Hoedjes et al.,2011)suchas T. remus.

Parasitoidscanchangetheirinnatepreferencesforodorcues thatguidethemtopatchesofhosts(Hoedjesetal.,2011). Associ-atingthesignslearnedduringparasitismorduringdevelopment enablesparasitoidfemales tolocateandparasitizeitshostwith greaterefﬁciencyandspeed(Cobert,1985;Nurindahetal.,1999;

Hoedjesetal.,2011),aphenomenonknownas_{␣-conditioning}or

associativelearning(Vinson,1998;Nurindahetal.,1999). There-fore,althoughfemale parasitoidshave aninnate preference for certain odors, foraging efﬁciency of most species is optimized byassociativelearning (Hoedjes etal.,2011).Parasitoidswhich hadexperiencedthepresenceofacertainhostspecies,thereafter narrowtheir(olfactory)‘searchimage’bylearning,asaformof temporalspecialization(Hoedjesetal.,2011).

Inaddition,morphologicalcharactersarelistedintheliterature asgoodindicatorsoftheﬁtnessandfertilityofadultparasitoids fromdifferenthostsandrearingfacilities.Changinghostspecies canclearlyimpactparasitoidmorphology,asreportedfordifferent speciesofthegenusTrichogramma(KazmerandLuck,1991;Grenier etal.,2001).Differencesamonghostscanbeduetovarious rea-sons.Forexample,S.frugiperdalaysitseggsinsuperposedmasses whileC.cephalonicalaysitseggsindividually.Thiscanaffectnot onlyparasitismbutalsothehost’ssuitabilityforparasitoid devel-opment(Cônsolietal.,1999),directlyaffectingthequalityofthe producedparasitoids.Therefore,tostudythesedifferencesinorder todetermineanappropriatehostforparasitoidmassrearingthat maximizesproduction,reducescosts,anddoesnotchangethe mor-phologicalcharactersofnaturalenemiesmightbeimportantforthe successofabiologicalcontrolprogram(Vazetal.,2004).

EventhoughindividualsofT. remusrearedonC.cephalonica weresmaller(mainlyintheirwingdimensions)thanindividuals rearedonS.frugiperdaeggs,noimpairmentinflyingcapacitywas observedinthelaboratorytest(shortdistance).Thesimilarityin thepercentagesofflyingindividualsfromC.cephalonica (genera-tionsF1,F8,F13,andF19)andindividualsfromthenaturalhostS. frugiperdaindicatesthatwhilethereductioninwingsizewas sig-nificant,itwasnotsufficienttocompromisetheflightabilityof theinsect.Theaveragepercentage(≈83%)ofparasitoidscaptured

onthecover(“ﬂyers”)wassimilartothatfoundbyotherauthors usingthesameprotocolforotherparasitoidspecies.Rodrigueset

al.(2009)foundaveragesfrom85.9to97.7%ofﬂyingindividuals

andPrezottietal.(2002)reportedmeanpercentagesbetween74.7

and90.6%forT.pretiosum.Thesimilarityofresultssuggeststhat theprotocoltestedcanalsobeusedtostudytheﬂightactivityofT. remusforqualitycontrolinmassrearingfacilities.

Theaveragepercentage of“walkers”caughtintheglue ring (_≈16%) washigherthan that obtainedin otherstudies usingT. pretiosum(Prezottietal.,2002;Rodriguesetal.,2009),whichis probablyrelatedtobehavioral differencesbetweenspecies.The percentageoftheseindividualswithdeformitiessuchasstuntedor foldedwingswaslessthan1%.Thisconfirmsthatthevisual obser-vationofthepercentageofindividualswithdeformedwingsalone isinsufficienttocharacterizethequalityoftheparasitoid,since almostallofthe“walkers”apparentlyhadnormalwings(Prezotti etal.,2002).Thesenon-flyingindividualsshouldbebetter evalu-atedbeforedeterminingwhethertheycouldhaveanegativeeffect onbiologicalcontrolprograms.GardnerandLenteren(1986) con-sideredthatbothflyingandwalkingareimportantfeaturesforthe performanceofnaturalenemiesinfieldconditions,astheyrelate toforaginganddispersal.

Considering both the morphometry and the flight test, our resultssuggestthatthehost-specificsizedifferencesofT.remus especiallyregarding winglengthand width,didnot necessarily affecttheflightactivityoftheparasitoidsincethepercentageof “flyers”didnotsignificantlydifferbetweenhosts.Inthefuture,the mostappropriatenumberofinsectstobereleasedshouldbe stud-ied,basedontheparasitismcapacityofT.remus,inordertotest thehypothesisthatreleasingagreaternumberofT.remusreared onC.cephalonicawillbeaseffectiveasreleasingasmallernumber ofthesameparasitoidrearedonS.frugiperda.

Other biological characteristics may alsobe affected due to changesinparasitoidsize.Forexample,innatureitis common toﬁnd increasingfertility withincreasingadult size.Chau and

Mackauer(2001)reportedthattheparasitoidMonoctonus

paulen-sis(Ashmead)(Hymenoptera:Braconidae)preferredlargeraphids, whichwasunderstoodasaprocessofselectiontomaximizetheir fertility(number,size,andqualityofeggs).Inaddition,the qual-ityofthehostisnotsimplyrelatedtosize,reﬂectingthebiomass availabletobeconsumedbytheparasitoid,butalsotothe devel-opment period. To maximize its size in low-quality hosts, the parasitoidcanreduceitsgrowthrateand increasethe develop-mentperiod(SequeiraandMackauer,1992).Adultparasitoidscan alsoincreasetheirlifespanduringtheabsenceof suitablehosts

(Carneiro et al., 2009) or even develop mechanisms of oocyte

absorptiontophysiologicallysynchronizeeggformationwithhost availability(Chabi-Olayeetal.,2001).Therefore,otherbiological parametersstillneedtobeevaluatedsuchasparasitoidfinding abil-ity,parasitismcapacity,andparasitoidfieldefficacyinordertohave amorecompletepictureofhostchangeeffectsonparasitoid biol-ogy.However,fastlaboratorytestsareneededinrearingfacilities andtheoneusedinthisstudymightbeusefultorapidlyindicate parasitoidquality.Inaddition,takingintoconsiderationtheresults discussedhere,thereisaclearindicationthatC.cephalonicacanbe usedasafactitioushostformassrearingofT.remus.

Conﬂictsofinterest

Theauthorsdeclarenoconﬂictsofinterest.

Acknowledgements

Authors wish to thank Embrapa Soybean and the sponsor agenciesCAPESandCNPqforﬁnancialsupportandscholarships

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provided.ThanksarealsoextendedtoDagmarFrischandtothe edi-torof“AmericanJournalExperts”forprovidingEnglishrevisions. ThispaperwasapprovedforpublicationbytheEditorialBoardof EmbrapaSoja.

References

Bueno,R.C.O.F.,Bueno,A.F.,Xavier,M.F.C.,Carvalho,M.M.,2014.Telenomusremus (Hymenoptera:Platygastridae)parasitismoneggs ofAnticarsiagemmatalis (Lepidoptera:Eribidae)comparedwithitsnaturalhostSpodopterafrugiperda (Lepidoptera:Noctuidae).Ann.Entomol.Soc.Am.107,799–808.

Bueno,R.C.O.F.,Parra,J.R.P.,Bueno,A.F.,2009.Biologicalcharacteristicsand ther-malrequirementsofaBrazilianstrainoftheparasitoidTrichogrammapretiosum rearedoneggsofPseudoplusiaincludensandAnticarsiagemmatalis.Biol.Control 51,355–361.

Burr,I.W.,Foster,L.A.,1972.ATestforEqualityofVariances.UniversityofPurdue, WestLafayette.

Carneiro, T.R.,Fernandes, O.A.,Cruz, I.,2009. Influência da competição intra-específicaentrefêmeasedaausênciadehospedeironoparasitismodeTelenomus remusNixon(Hymenoptera,Scelionidae)sobreovosdeSpodopterafrugiperda (J.E.Smith)(Lepidoptera,Noctuidae).Rev.Bras.Entomol.53,482–486. Cave,R.D.,2000.Biology,ecologyanduseinpestmanagementofTelenomusremus.

Biocontrol21,21–26.

Chabi-Olaye,A.,Schulthess,F.,Poehling,H.M.,Borgemeister,C.,2001.Factors affect-ingthebiologyofTelenomusisi(Polaszek)(Hymenoptera:Scelionidae),anegg parasitoidofcerealstemborersinWestAfrica.Biol.Control21,44–54. Chapman, J.W., Williams, T., Martinez, A.M., Cisneros, J., Caballero, P., Cave,

R.D., Goulson, D.,2000. Does cannibalism in Spodoptera frugiperda (Lepi-doptera:Noctuidae)reducetheriskofpredation?Behav.Ecol.Sociobiol.48, 321–327.

Chau,A.,Mackauer,M.,2001.PreferenceoftheaphidparasitoidMonoctonus paulen-sis(Hymenoptera:Braconidae,Aphidinae)fordifferentaphidspecies:female choiceandoffspringsurvival.Biol.Control20,30–38.

Clarke,G.M.,McKenzie,L.J.,1992.Fluctuatingasymmetryasaqualitycontrol indi-catorforinsectmassrearingprocesses.J.Econ.Entomol.85,2045–2050. Cobert,S.A.,1985.Insectchemosensoryresponses:achemicallegacyhypothesis.

Ecol.Entomol.10,143–153.

Cônsoli,F.L.,Kitajima,E.W.,Parra,J.R.P.,1999.Ultrastructureofthenaturaland factitioushosteggsofTrichogrammagalloiZucchiandTrichogrammapretiosum Riley(Hymenoptera:Trichogrammatidae).Int.J.InsectMorphol.Embryol.28, 211–229.

Dutton, A., Bigler, F., 1995. Flight activity assessment of the egg parasitoid Trichogrammabrassicae(Hym.:Trichogrammatidae)inlaboratoryandﬁeld con-ditions.Entomophaga40,223–233.

Gardner,S.M.,Lenteren,J.C.,1986.Characterizationofthearrestmentresponsesof Trichogrammaevanescens.Oecologia8,265–270.

Gautum,R.D.,1986.Inﬂuenceofdifferentnoctuidhostsontheparasitisationby TelenomusremusNixon(Scelionidae:Hymenoptera).J.Entomol.Res.10,70–73. Greene,G.L.,Leppla,N.C.,Dickerson,W.A.,1976.Velvetbeancaterpillar:arearing

procedureandartiﬁcialmedium.J.Econ.Entomol.69,487–488.

Grenier,S.,Grille,G.,Basso,C.,Pintereau,B.,2001.Effectsofthehostspeciesand thenumberofparasitoidsperhostonthesizeofsomeTrichogrammaspecies (Hymenoptera:Trichogrammatidae).Biocontr.Sci.Technol.11,21–26.

Hoedjes,K.M.,Kruidhof,H.M.,Huigens,M.E.,Dicke,M.,Vet,L.E.M.,Smid,H.M.,2011. Naturalvariationinlearningrateandmemorydynamicsinparasitoidwasps: opportunitiesforconvergingecologyandneuroscience.Proc.R.Soc.B278, 889–897.

Kazmer,D.J.,Luck,R.F.,1991.Femalebodysize,ﬁtnessandbiologicalcontrol qual-ity:ﬁeldexperimentswithTrichogrammapretiosum.LesColloquesdeI’INRA56, 37–40.

Nurindah,G.G.,Cribb,B.W., Gordh,G.,1999.Effects ofphysiological condition andexperienceonovipositionbehaviourofTrichogrammaaustralicumGirault (Hymenoptera:Trichogrammatidae)oneggsofHelicoverpaarmigeraHubner (Lepidoptera:Noctuidae).Aust.J.Entomol.38,104–114.

Parra, J.R.P.,2001.Técnicasde criac¸ãode insetospara programasdecontrole biológico.FEALQ,Piracicaba.

Parra,J.R.P.,1997.Técnicasdecriac¸ãodeAnagastakuehniella,hospedeiro alter-nativoparaproduc¸ãodeTrichogramma.In:Parra,J.R.P.,Zucchi,R.A.(Eds.), Trichogramma e ocontrolebiológico aplicado.FEALQ/USP, Piracicaba,pp. 121–150.

Perkins,W.D.,1979.Laboratoryrearingofthefallarmyworm.FloridaEntomol.62, 87–91.

Pomari,A.F.,Bueno,A.F.,Bueno,R.C.O.F.,MenezesJunior,A.O.,2012.Biological char-acteristicsandthermalrequirementsofthebiologicalcontrolagentTelenomus remus(Hymenoptera:Platygastridae)rearedoneggsofdifferentspeciesofthe genusSpodoptera(Lepidoptera:Noctuidae).Ann.Entomol.Soc.Am.105,72–81. Pomari-Fernandes,A.,Bueno,A.F.,Queiroz,A.P.,DeBortoli,S.A.,2015.Biological parametersandparasitismcapacityofTelenomusremusNixon(Hymenoptera: Platygastridae)rearedonnaturalandfactitioushostsforsuccessivegenerations. Afr.J.Agric.Res.10,3225–3233.

Pomari-Fernandes,A.,Queiroz,A.P.,Bueno,A.F.,Sanzovo,A.W.,DeBortoli,S.A.,2014. TheImportanceofRelativeHumidityforTelenomusremus(Hymenoptera: Platy-gastridae)ParasitismandDevelopmentonCorcyracephalonica(Lepidoptera: Pyralidae)andSpodopterafrugiperda(Lepidoptera:Noctuidae)Eggs.Ann. Ento-mol.Soc.Am.,1–7.

Prezotti, L., 2001. Controle de qualidade de Trichogramma pretiosum Riley, 1879(Hymenoptera:Trichogrammatidae)emcriac¸õesdelaboratório.Tesede doutorado,ESALQ/USP,Piracicaba.

Prezotti,L.,Parra,J.R.P.,Vencovsky,R.,Dias,C.T.,Cruz,I.,Chagas,M.C.M.,2002. Testedevôocomocritériodeavaliac¸ãodaqualidadedeTrichogrammapretiosum Riley(Hymenoptera:Trichogrammatidae):Adaptac¸ãodemetodologia.Neotrop. Entomol.31,411–417.

Rodrigues,S.M.M.,Sampaio,M.V.,Miranda,J.E.,2009.Avaliac¸ãodacapacidadede vôo,parasitismoeemergênciadelinhagensdeTrichogrammapretiosumRiley (Hymenoptera:Trichogrammatidae).Arq.Inst.Biol.76,749–753.

Institute,S.A.S,2001.SASUser’sGuide:Statistics,Version8e.SASInstitute,Cary,NC. Sequeira,R.,Mackauer,M.,1992.Nutritionalecologyofaninsecthost-parasitoid

association:thepeaaphidAphidiuservisystem.Ecology73,183–189. Shapiro,S.S.,Wilk,M.B.,1965.Ananalysysofvariancetestfornormality(complete

samples).Biometrika52,591–611.

vanLenteren,J.C.,2003.QualityControlandProductionofBiologicalControlAgents: TheoryandTestingProcedures.CABI,Wallingford.

Vaz, L.A.L., Tavares, A.T., Lomônaco, C., 2004. Diversidade e tamanho de himenópterosparasitoidesdeBrevicorynebrassicaeL.eAphisneriiBoyerde Fonscolombe(Hemiptera:Aphididae).Neotrop.Entomol.33,225–230. Vinson,S.B.,1998.ThegeneralhostselectionbehaviorofparasitoidHymenoptera

andacomparisonofinitialstrategiesutilizedbylarvaphagousandoophagous species.Biol.Control11,79–96.