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Tomato,Lycopersicon esculentumMill,is one of the most important vegetable cropsin Brazil, with 55,000 ha under production,

yielding 1.5 million ton/year (FAO 1993). Theaverage production is about 50 ton/ha. How-ever, in Rio de Janeiro State, the tomato pro-duction average is higher (70 ton/ha) and rep-resents 80% of the vegetable crops on themarket.

The tomato-fruit borer NeoleucinodeselegantalisGuene (Lepidoptera: Crambidae)is the most important pest in several tomatogrowing regions of Central and SouthAmerica, including some Caribbean Islands

(Salas et al.1992). The larvae feed inside thetomato fruit, causing estimated losses of upto 45%. After the larvae leave the tomato fruit,they pupate in the soil or enfolded in leaves(Marcano 1991). After mating, females de-

posit their eggs on small fruits (23 mm diam)and under the calyx (Blackmer et al. - in

press). Each moth is capable of laying 160eggs (Marcano 1991). The majority of eggshatch during the first hour of scotophase andapproximately one hour later the larvae enter

in the fruit (Blackmer et al.in press). Currentcontrol strategies include two to three appli-cations of pesticides per week (Reis & Souza1996), and cultural practices such as the de-struction of infested fruits or wild solanaceoushosts (Gallo et al.1988). Once the larvae en-ter the fruit, pesticides are ineffective and sub-lethal doses of pesticides can lead to insecti-cide resistance problems. Therefore, newstrategies for monitoring and controllingN.elegantalisneed to be developed such as theuse of a sex pheromone (Jutsum & Gordon1989, Ridgway et al.1990).

Synthetic sex pheromone in Lepidopterahave been widely used for monitoring, tim-ing spray and controlling methods (eg. lure &kill, mass trapping or matting disruption)(Roelofs & Card 1987, Jutsum & Gordon1989, Ridgway et al.1990). No informationhas been published on the mating behaviorand sex pheromone ofN. elegantalis,althoughit has been know that virgin females of Lepi-dopteran attract male for matting from longdistances. Therefore, this paper aimed to study

the emergence of adults and mating behaviorof female of the tomato-fruit borer, N.elegantalis.

Extraction and evaluation of the sexpheromone glands were also evaluated withina wind tunnel in order to confirm the sex

pheromone components.

Material and Methods

Insects. Tomato fruits showing the typicalscared entrance hole of the larva were col-lected from So Jos de Ub and Itaperuna,

state of Rio de Janeiro, Brazil. They weremaintained in the laboratory until the larvaeleft the fruit to pupate. Pupae were sexed ac-cording to Butt e Cantu (1962). Pupae andadults were kept in transparent perspex cages(30x30x30 cm) at 23 1oC, on a 12L:12D

photoperiod and 70% RH. Male adults weremaintained in separate BOD chambers toavoid contamination from the female sex

pheromone.

Timing of Adult Emergence.Male (N=100)and female (N=100) pupae were kept inperspex cages and hourly observed for adultemergence during 24 hours. As adultsemerged, they were recorded and removedfrom the cage. The observations during thescotophase were made with a torch that hadthe light source covered with red cellophane.

Calling Behavior. The observations of call-ing behavior were carried out at 231C and

643% RH, beginning one hour beforescotophase. Approximately 20 couples were

placed in screened cages (30x30x30 cm) twohours prior to the observations. The callingand mating behavior of newly emerged (

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An. Soc. Entomol. Brasil 29(3) 455Setembro, 2000

Gland Extracts. Abdominal tips of virgin fe-males were extracted for 10-15 min. in hexaneand kept in glass microcapillary tubes in a

freezer (-20oC) until behavioral tests could beconducted.

Wind Tunnel Tests. Behavioral tests werecarried out within a flight tunnel (80x30x30cm) calibrated to 25 cm s -1 , 5 lux (light inten-sity), 241oC and 65% R.H. The airflow was

produced by an electrical fan and was puri-fied by a 5 cm layer of activated charcoal fil-ter. The odor source was placed at 80 cm up-wind from the release platform (37 cm lenght

x 4 cm diam.) of the male moths. Groups ofthree males were placed in a screened cage(5x5x10 cm) and allowed to acclimatize tothe tunnel condition for at least two hours priorto testing. The males were tested once, dur-ing the female calling period. The odor sourceconsisted of either two virgin females placedwithin a 3x5 cm diam. screened cage or agland extract containing two female equiva-lents (2 FE) or hexane as control. Gland ex-tracts or hexane were placed on separated 1x1

cm filter paper and tested after the solvent hadevaporated. The number of males taking off,

performing upwind flight behavior towardsthe odor source, landing at the source and at-tempting to copulate with the odor source wererecorded. A smoke plume of hydrochloric acidand ammonium hydroxide was regularly visu-alized to ensure that the structure of the plumewas conical and that it passed over the plat-form containing the males.

Results and Discussion

Emergence of Adults. The emergence ofadults ofN. elegantalisis governed by a cir-cadian rithym and this behavior is very com-mon among the lepidopteran (Matthews &Matthews 1988, Horodyski 1996). Both sexesemerged only during the scotophase. The fe-males began to emerge during the 1st hour ofscotophase, whereas the males began toemerge in the 2nd hour. The highest emer-gence rate occurred during the 4th hour for

both sexes (Fig.1). Adult emergence was pe-

riodic, occurring mainly early evening until7th hour of scotophase. The results suggestthat there is a synchronized pattern of emer-

gence of adult moths.

Calling Behavior and Duration of Copula-tion.During the photophase (the adult rest-ing period), both sexes curved their abdomensupward and kept their antenna motionless.This position is typical for calling behaviorof several species of moths such as the to-mato leaf miner Tuta absoluta (Meyrick)(Hickel et al. 1991), the tomato pinworm

Keiferia lycopersi cella (Walsingham)

(McLaughlin et al. 1979) and the pinkbollworm Pectinophora gossypiella(Saunders) (Tth 1985). During the calling

behavior,N. elegantalisfemales maintainedtheir abdomen straight in an horizontal posi-tion while moving their antennae up and downvertically. The males during activity also per-formed such position and movements of an-tennae. The courtship behavior began whenmales flew near a calling female (usually 1-2cm) and walked towards her while rapidly

vibrating his wings and opening the hairbrushes. Occasionally, a female would fly offwhen approached.

In general, the percentage of mating ofN.elegantalisin laboratory was low. Such re-sults could be a reflect on the difficulty of rear-ing N. elegantalis in laboratory conditions(Alvaro E. Eiras & Jos R. P. Parra, unpub-lished). Newly emerged (

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456 Eiras

hour (27.5%) (Fig. 3). Thus, these results sug-

gest that the best time to extract the sexpheromone glands would be between the 5th

and 9th hour of scotophase, using 48-72 h old

virgin femaleN. elegantalis.The majority of Lepidoptera mate during

Figure 1: Emergence time for female ( ) and male (+)N. elegantalisduring a 12 L:12D cycle(scotophase : photophase) in the laboratory (N = 100).

0

5

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30

11 12 1 2 3 4 5 6 7 8 9 10 11 12

Hour

%e

mergence

Scotophase

Figure 2:Mating ofN. elegantaliscouples of different ages in the laboratory.

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the scotophase (Roelofs & Card 1987) andthe periodicity of the calling behavior has beenconsidered one of the main mechanism en-suring reproductive isolation (Card &Roelofs 1973). One of the characteristics ofinsects that have a short life span is that mat-ing occurs shortly after emergence (Matthews& Matthews 1988).

There is no published data on the lifespanofN. elegantalisin the field, but observationsof caged virgin female held in a trap in thefield, survived up to 14 days (Alvaro Eiras,unpublished data). Adults reared in the labo-ratory with different liquid diets survived upto 15 days (mean 9.9 1.5 days for males)and 14 days (8.8 2.3 for females) (Andradeet al.,unpublished). There is no evidence thatwhether this species is migratory. However,this moth has the ability to move between to-mato fields, which can be separated by quitea distance.

The duration of the copulation rangedfrom 70 min. (24 h old) up to 224 min. (96 hold). The longest period of copulation was

observed for 48 h, although there was no dif-ference between the ages (Fig. 4).

Wind Tunnel.The observations of the up-wind flights ofN. elegantalisin the wind tun-nel showed that males exhibited significantlyhigher response levels to the gland extract thanto control (Fig. 5). Only the take-off rate wassimilar when the source was either a virginfemale or the gland extract. However, the up-wind flights, flights close to the source, land-

ing rates and attempts to copulate at the sourcewere significantly greater for the gland extractthan for the virgin female. Very few upwindflights to the control treatment were observed.Although the virgin females exhibited the call-ing behavior position when they were pre-sented as the odor source, the behavior ofmales suggested that the females were not re-leasing sex pheromone. The low proportionof couples mating (Figs. 2 and 3) under labo-ratory conditions suggests that not all virginfemales engage in calling behavior when con-ditions (age and hour of scotophase) seem

Figure 3. Percentage of mating of N. elegantalis under laboratory conditions duringscotophase (N=422) (23oC; 12L:12D, 65% RH).

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458 Eiras

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24 48 72 96

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Duration(min.)

Figure 4: Mean duration (s.e.) of N. elegantaliscopulating at different ages.

Figure 5: Behavioral responses of theN. elegantalismales to virgin females (n=35), control(n=15) and gland extracts (n=72) in the wind tunnel. Bars mean standard error.

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Take off Upwind flight Flight close Landing Copulation

%o

frespon

se

Control Virgin female Gland extract

insect and the environmental conditions (i.e.,temperature, relative humidity, wind speed)

influence calling behavior. AsN. elegantalisis a specialist on solanaceous plants, host plant

otherwise favorable. Many factors could in-fluence the females to elicit upwind flight

(wind tunnel) and mating (calling behavior).It is likely that the physiological state of this

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volatiles may act as additional cues that stimu-late calling behavior. The fact that matingoccurs on host plants is important in sex se-

lection and mating finding. In many speciesof herbivorous insects, both sexes are attractedto the host plant odors. In some species, malesare attracted to females in the presence of host

plant odor. For example, the males of the leekmoth, Acrolepiopsis assectella (Zeller) areattracted in the presence of the odors of leek(Bernays & Chapman 1994).

At the moment, sex pheromone gland ex-tracts of 48-72 h virgin femaleN. elegantalisis being submitted to chemical analysis in or-

der to identify the active compounds.

Acknowledgements

This work was supported by the Interna-tional Foundation for Science (IFS, F/2478-1), CNPq (grant # 520817/96-6) andFundao de Amparo Pesquisa do Estadodo Rio de Janeiro (FAPERJ, E26.170.363/95).The technical support from EMATER-RJ (SoJos de Ub and Itaperuna, RJ), Arli de

Ftima, Ederaldo Azeredo and DeniseMoreira (LPP/CCTA/UENF) are also ac-knowledged. Thanks also to Dr. J.L Blackmerand the referees for their corrections of themanuscript.

Literature Cited

Bernays, E.A. & R.F. Chapman. 1994.Host-plant selection by phytophagous insects.New York. Chapman H Hall. 312p.

Blackmer, J.L., A.E. Eiras & C.L.M. Souza.Oviposition Preference ofNeoleucinodeselegantalis (Guene) (Lepidoptera:Crambidae) and Rates of Parasitism byTrichogramma pretiosum Riley(Hymenoptera: Trichogramma- tidae) on

Lycopersicon esculentumin So Jos deUb, RJ, Brazil. An. Soc. Entomol. Brasil(in press).

Butt, B.A. & E. Cantu. 1962. Sexdetermination of Lepidopteran pupae.

Washington, USDA. 7 p.

Card, R.T. & W.F. Roelofs. 1973.

Temperature modification of the male sexpheromone response and factors affectingfemale calling inHolomelinaimmaculata(Lepidoptera: Arctiidae). Can. Entomol.105: 1505-1512.

FAO 1993.Quartely Bulletin of Statistics.Rome, v.6. no.4

Gallo, D., O. Nakano, S. Silveira Neto,R.P.L. Carvalho, G.C. De Batista, E.

Berti Filho, J.R.P. Parra, R.A. Zucchi,S.B. Alves & J.D. Vendramim. 1988.Manual de Entomologia Agrcola.Editora Agronmica Ceres, So Paulo.649 p.

Hickel, E.R., E.F. Vilela, J.O.G. Lima &T.M.C. Della Lucia. 1991.Comporta-mento de chamamanto de Scrobipalpulaabsoluta (Lepidoptera: Gelechiidae).Pesq. Agropec. Bras. 26: 827-835.

Horodyski, F.M. 1996. Neuroendocrinecontrol of insect ecdysis by eclosionhormone. J. Insect Physiol. 42: 917-924.

Jutsum, A.R. & R.F.S. Gordon. 1989.Insectpheromone in plant protection. JohnWilley & Sons. 369p.

Marcano, R. 1991. Ciclo biolgico delpe rforador de l fru to de l tomateNeoleucinodes elegantalis Guenee(Lepidoptera: Pyralidae), usando

berenjena (Solanum melongena) comoalimento. Bol. Entomol. Venez. 6: 135-141.

Mattews, R.W. & J.R. Mattews. 1988 .Insect Behavior. New York, John Wiley& Sons, 507p.

Mclaughlin, J.R., A.Q. Antonio, S.L. Poe& D.R. Minnick. 1979.Sex pheromone

biology of the adult tomato pinworm,

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