BEHAVIOR Courtship Behavior in rosaceana and pyrusana (: )

1 2 3 TOMISLAV CURKOVIC, JAY F. BRUNNER, AND PETER J. LANDOLT

Ann. Entomol. Soc. Am. 99(3): 617Ð624 (2006) ABSTRACT The characterization of courtship behavior in two sympatric and synchronic leafroller species, Choristoneura rosaceana (Harris) and Kearfott, indicated that only pher- omone permeated airßow was needed as a releaser to initiate the male mating sequence. Mating ethograms demonstrate that males of both species perform six observable, discrete, and homogeneous steps: 1) wing fanning; 2) Þrst contact; 3) male next to female (mostly in C. rosaceana), head-to-head (only P. pyrusana); 4) curled abdomen; 5) genitalia engagement; and 6) end-to-end position (mating). The sequences were highly stereotypic, suggesting that once a male starts the mating sequence, the rest of the steps will most likely follow. First contact with the female was a preprogrammed response, not requiring further cues. Copulation was more likely when the female remained stationary after Þrst contact. Unsuccessful mating sequences were frequent during the study because females escaped by walking away, turning around, or jumping away. Because courtship behavior is a mechanism to select sexual partners, it is possible to hypothesize that responses resulting in an unsuccessful mating (assumed to be rejection) validate this mechanism. The mating sequence of C. rosaceana best matches the simple courtship behavior model, whereas the sequence in P. pyrusana resembles an interactive courtship. Overall results indicate that courtship behavior in both species would be compatible with attracticide (i.e., sex pheromone ϩ insecticide) technology that requires direct contact between males and the pheromone source.

KEY WORDS courtship behavior, Pandemis pyrusana, Choristoneura rosaceana

Sexual behavior is best understood in the context of of an attracticide, it is important to Þrst understand its the sexual selection theory, which states that differ- normal sexual behavior (Krupke 1999). Modern at- ential reproduction occurs between conspeciÞc indi- tracticides are baits that combine the use of synthetic viduals within the same sex (Cade 1985). Males try to pheromones as the attractant and a contact insecticide increase the number of mates (and compete among that kills the target species (Charmillot et al. 2000). themselves), and females select sexual partners to This technology represents a selective alternative to enhance offspring Þtness. Thus, both sexes invest dif- the conventional use of broad-spectrum insecticides. ferentially (Andersson and Iwasa 1996), e.g., females Attracticides have been developed and reported for in eggs and pheromone production and males in fe- several species of Lepidoptera, e.g., Cydia pomonella male searching and courtship behavior. Courtship be- (L.) (Tortricidae), Pectinophora gossypiella (Saun- havior is deÞned as the short-range behavioral se- ders) (Gelechiidae), and Choristoneura rosaceana quence before copulation (Alexander et al. 1997). (Harris), and Pandemis pyrusana Kearfott (Tortrici- use courtship behaviors as mechanisms to en- dae) (Hofer and Angst 1995; Charmillot et al. 1996, sure successful conspeciÞc mating and select pheno- 2000; Curkovic and Brunner 2003, 2005; Curkovic types among sexual partners (Cade 1985, Alexander et 2004). al. 1997). Descriptions of mating and courtship behavior have Understanding of sexual behavior is necessary when been published for only a few tortricid species. In developing pest control strategies based on synthetic some species, courtship is regulated by female and sex pheromone sources (Lingren et al. 1982), other- male clues. For example, in Grapholita molesta wise failures can occur (Silverstein 1981). Therefore, (Busck) the male Þrst responds to the female phero- to evaluate the potential of techniques designed to mone from long distance, produces a courtship pher- prevent successful mating of a target species, e.g., use omone (short-range approach), and Þnally makes physical contact with the female to express the com- 1 Departamento de Sanidad Vegetal, Facultad de Ciencias Agro- plete behavioral sequence that ends in a successful no´micas, Universidad de Chile, Casilla 1004, Santiago, Chile. mating (Baker and Carde´ 1979). However, in most 2 Tree Fruit Research and Extension Center, Washington State reports, mating depends only on pheromone-medi- University, Wenatchee, WA, 98801. 3 USDAÐARS Yakima Agricultural Research Laboratory, Wapato, ated attraction and acceptance by the female of a WA 98951. conspeciÞc male (Castrovillo and Carde´ 1980, Shimizu

0013-8746/06/0617Ð0624$04.00/0 ᭧ 2006 Entomological Society of America 618 ANNALS OF THE ENTOMOLOGICAL SOCIETY OF AMERICA Vol. 99, no. 3 and Tamaki 1980, Grant 1987). Reports by Delisle ing excessive pheromone “contamination” that could (1995) and Knight and Turner (1998) addressed the affect normal male behavior. The wind tunnel pro- sexual behavior for C. rosaceana and P. pyrusana but duced an air ßow by suction that exhausted any pher- did not describe a courtship sequence for either spe- omone-permeated air out of the tunnel and out of the cies. building. Openings of the mating arena tube were The objectives of this study were to characterize the placed parallel to the airßow. courtship behavior for both C. rosaceana and P. pyru- Management. A single calling female was in- sana. SpeciÞcally, we sought to deÞne body parts Þrst troduced into a mating arena tube at least 2 h before involved in contact between conspeciÞc males and observations and Þlming and then placed next to females and to determine whether there was any ev- the wind tunnel until observations were begun. Males idence of short-range cues (male or female produced) were placed individually into mesh cylinder cages required for successful mating. These two tortricid (4 cm in diameter by 2 cm in height), covered with a species often coexist in Washington ( plastic lid (LS1, Prairie Packaging, Bedford Park, IL), spp.) orchards and broad-spectrum insecticides are provided with honey solution via a cotton wick, and the primary tactic used for their control (Beers et al. acclimated on a table next to the wind tunnel (upwind 1993, Brunner 1994). Knowledge of courtship behav- the females) at least 2 to 3 h before experiments were ior is an important Þrst step in the development of an initiated. Observations were made in the Þrst 2Ð4 h of attracticide formulation for both species. Differences the scotophase, which corresponds to the sexual ac- or subtleties in close range mating behavior could alter tivity period for both C. rosaceana and P. pyrusana how an attracticide formulation is developed or indi- (Evenden 1998, Knight and Turner 1998). Females cate the need for components other than the sex could be readily observed transitioning from a resting pheromone. state (Fig. 1B) to a calling (releasing pheromone) state (Fig. 1C). A single male was introduced inside the mating arena (at the downwind end) after a fe- Methods and Materials male was observed to be calling. The distance between Insects. C. rosaceana and P. pyrusana pupae were both sexes at this point was 10Ð15 cm. Five to 10 obtained from colonies maintained at the Washington mating arena tubes were used in each observation and State University Tree Fruit Research and Extension Þlming session. Laboratory conditions during obser- Center, Wenatchee, WA. Larvae were reared follow- vations were 21 Ϯ 1ЊC, 55 Ϯ 5 RH, 30 Ϯ 4 cm/s ing methods of Shorey and Hale (1965). Colonies were (airßow), and 2 lux. maintained in walk-in growth chambers at 23 Ϯ 2ЊC Recording and Photographing Moth Behavioral Se- and 40Ð50% RH, under a photoperiod of 16:8 (L:D) h quences. Visual observations were made after accli- by using eight ßuorescent lights (Ϸ1,900 lux in the mation of the observer for 10 min and by using a center of the room). Pupae were sexed, washed in 5% ßashlight covered with a red Þlter (gelatin 29, Eastman commercial bleach solution, placed in small groups Kodak, Rochester, NY). Two models of manual video (15Ð20) in 96-ml closed plastic cups (P325, Solo Cup cameras with infrared illumination capabilities were Co., Urbana. IL), provided with honey water solution used to record the behavioral sequences (Sony 360x (20% U.S. grade honey ϩ 2 g of FABCO-1 [mold model CCD-TRV67 and Sony 120x DCR-PC100). The inhibitor, formaldehyde substitute], BioServ, French- camera lens was set against the mating arenas (tubes). town, NJ), and kept in a growth chamber under con- Recordings were made from below, allowing the ob- ditions described above. Male and female pupae were servation of detailed steps during the mating se- held in different chambers to avoid any preexposure quence, through the Plexiglas, within 2 to 3 cm from to conspeciÞc individuals of the opposite sex. Upon the female. Pictures of individual insects (e.g., calling) emergence, groups of four or Þve adults of the same or couples performing the mating sequence in plastic sex were placed in 96-ml plastic cups and provided petri dishes were taken from below using a digital with a honey solution via cotton wicks. Two- to 4-d-old camera (Nikon Coolpix 950, 3ϫ optical). A 127-cm males and 2- to 6-d-old females were used in experi- color projection system (Panasonic model PTJ- ments, because preliminary results showed Ͼ97% of 4578R) was used to play tapes directly from the vid- males and 100% of females survived in these age cat- eocameras and to record individual moth behavior. egories (Curkovic 2004), and they were sexually ma- Ethogram and Data Analysis. Observable events in ture at those ages (Delisle 1995). the mating sequence were recorded and presented in Observation Arenas. The arena for observation and ethograms, where the sequences of behavioral steps recording of behavioral sequences was made of a and their respective frequencies are shown (Cas- transparent Plexiglas tube (20 cm in length by 10 cm trovillo and Carde´ 1980, Haynes and 1984). Con- in diameter) with nylon organdy cloth at both ends, tingency tables were developed of frequencies of spe- which allowed airßow through the arena. One end had ciÞc mating behavior actions after Þrst contact of a hole in its center to allow for the introduction of females by males. The sequence was analyzed assum- . The mating arena tube was placed at the up- ing that a speciÞc behavior was dependent on the wind end of an indoor wind tunnel where the metal immediately preceding step; thus, its frequency be- duct (upwind end) was removed. The positioning of came a conditional probability (Fagen and Young the mating arena tube inside of a wind tunnel was 1978). Pairs of moths were observed until a total of at important for conducting the experiment while avoid- least 30 for each species had completed all sequences May 2006 CURKOVIC ET AL.: COURTSHIP BEHAVIOR OF C. rosaceana AND P. pyrusana 619

Fig. 1. Behavioral steps during successful and unsuccessful courtship sequences for C. rosaceana. (A) Resting male. (B) Resting female. (C) Calling female. (D) Male activated. (E) Male wing fanning. (F) Male wing fanning while walking. (G) First contact with posterior of female. (H) Male next to female. (I) Male with curved abdomen. (J) Head-to-head contact (P. pyrusana only). (K) Genital contact. (L) Mating pair. (M) Male making unsuccessful copulation attempt. successfully, ending in a mating. For both species, Results and Discussion contingency tables were developed for 1) the court- ship outcome based on the female body part Þrst The number of couples needed to obtain 30 com- contacted by males and 2) courtship outcome based plete mating sequences (ending in engagement of on the female response to Þrst contact by males. Chi- genitalia) was much higher in P. pyrusana (n ϭ 139) square tests (␣ ϭ 0.05) were performed for both spe- than in C. rosaceana (n ϭ 42). This difference was cies (SAS Institute 2002). because P. pyrusana females expressed the typical call- 620 ANNALS OF THE ENTOMOLOGICAL SOCIETY OF AMERICA Vol. 99, no. 3

Table 1. Number of C. rosaceana males, and percentage out of the total sequences (in parentheses), that first contacted a female body region during courtship attempts

Wing position Head Thorax Abdomen Terminalia Wings Total Elevated 9 9 35 10 11 74 Resting 4 1 1 6 23 35 Total 13 (11.9) 10 (9.2) 36 (33) 16 (14.7) 34 (31.2) 109 (100) Mateda 1 (3.2) 0 (0) 26 (83.9) 1 (3.2) 3 (9.7) 31 (100)

a Sequences ending in successful mating. ing posture (Fig. 1C) less frequently than C. rosaceana walking straight toward the pheromone source. De- (62 versus 93%), they accepted the male less often pending on the femaleÕs posture, the maleÕs head under experimental conditions, or a combination. In- and/or labial palps also might have made Þrst contact deed, the ratio of copulatory attempts to successful (FC) with the female body. sequences was Ϸ40% lower with C. rosaceana. The The FC (Fig. 1G and 1H) varied between the spe- P. pyrusana response was much more variable with cies in terms of the region of the female body Þrst very few pairs completing successful mating se- touched. In C. rosaceana, FC occurred mostly be- quences on some nights and relatively high numbers tween the male antennae/head and female abdomen on other nights. The ratio of copulatory attempts to (33%), wings (31.2%), terminalia (Matsuda 1976) total sequences, however, was similar in the males of (14.7%), head (11.9%), or thorax (9.2%) when ex- both species, 1.83 in C. rosaceana versus 1.85 in P. posed (Table 1). When only successful mating se- pyrusana, indicating that they attempted copulation in quences are considered, 83.9% of C. rosaceana males a similar way regardless of female response (accepting made FC with the female abdomen (Table 1). The or rejecting males). Indeed, some tortricid males will upper surface of female wing was contacted when attempt to copulate with conspeciÞc females not ex- they were lowered (Fig. 1H), e.g., when disturbed. pressing a calling posture (Palaniswamy et al. 1979). Occasionally, when the femaleÕs wing was raised in the Courtship Sequences in C. rosaceana and P. pyru- typical calling position (Fig. 1C), C. rosaceana males sana Males. Both C. rosaceana and P. pyrusana males were observed to contact the female body with their were inactive in airßow in the absence of a calling forelegs. Apparently WFW and FC are prepro- female. Other species tend to remain active through- grammed responses elicited by detection of phero- out the day, apparently because of some intrinsic basal mone in the airstream and required no further cues to sexual activity (Palaniswamy et al. 1979). C. rosaceana initiate a curled abdomen action (Fig. 1I) or copula- and P. pyrusana males rested on the substrate with tion attempt. No males curled their abdomen (CAB) their wings tentlike and the antennae projected back- or attempted copulation without FC with some part of ward, parallel to their body (Fig. 1A). Most pictures the femaleÕs body. FC with the female probably pro- presented in Fig. 1 are of C. rosaceana because be- vided a textural cue to the male or possibly an un- havioral steps during courtship for this species could known chemical cue, leading to a CAB and attempted be observed under illumination, whereas this was copulation, as observed in C. fumiferana by Grant much more difÞcult for P. pyrusana, which was more (1987). Copulation attempts seemed to be indepen- sensitive than C. rosaceana to almost any external stim- dent of any female releaser cue because males exe- ulus. However, the sequences portrayed were very cuted it quickly after they CAB, even when females similar for both species, except for the head-to-head were out of range or facing the opposite direction (Fig. 1J, HTH) step in P. pyrusana. (Fig. 1M). Most females of both species, Ϸ80%, oriented them- The mating behavioral sequence in P. pyrusana dif- selves perpendicular to the airßow when assuming the fered only slightly from C. rosaceana. Considering all calling position, i.e., releasing pheromone (Fig. 1C). of P. pyrusana courtship behaviors, FC was most fre- Once exposed to an airßow containing pheromone, quent between male head/antennae and the femaleÕs males of both species become activated. They slightly abdomen (28.1%), thorax (25.3%), head (21.2%), ter- raised their bodies from the substrate and projected minalia (16.4%), or wings (9%) (Table 2). However, their antennae perpendicular or forward relative to when only successful mating sequences were consid- the airßow direction and their hair pencils were ex- ered, P. pyrusana males showed less preference for tended slightly backward (Fig. 1D). These observa- a particular part of the female body Þrst contacted. tions suggest that pheromone-permeated air was the P. pyrusana males made FC most often with the fe- necessary initial cue to trigger the courtship sequence. maleÕs head (36.7%), abdomen (30.0%), or thorax Males then started wing fanning (Fig. 1E) while sta- (23.3%) before the next step, head-to-head contact tionary, followed by wing fanning while walking (Fig. 1J, HTH), in the courtship behavior sequence (Fig. 1 F, WFW) either in circles or upwind. Occa- (Table 2). sionally during WFW, the male antennae vibrated, It is thought that prominent and stereotyped court- apparently touching the substrate, and were possibly ship steps are incorporated into the mating sequence the Þrst male structure to contact the femaleÕs body, as they increase in their signal value, i.e., for species or because all males observed approached the female sexual identity, or for mate quality assessment (Phelan May 2006 CURKOVIC ET AL.: COURTSHIP BEHAVIOR OF C. rosaceana AND P. pyrusana 621

Table 2. Number of P. pyrusana males, and percentage out of the total sequences (in parentheses), that first contacted a female body region during courtship attempts

Wing position Head Thorax Abdomen Terminalia Wings Total Elevated 21 37 41 22 1 122 Resting 100021224 Total 31 (21.2) 37 (25.3) 41 (28.1) 24 (16.4) 13 (9) 146 (100) Mateda 11 (36.7) 7 (23.3) 9 (30) 0 (0) 3 (10) 30 (100)

a Sequences ending in successful mating. and Baker 1990). The HTH step within the courtship 0.13, dashed lines). Most P. pyrusana males perform six sequence has been reported in several species of steps to consummate a successful mating, including Pyralidae, where females are calling upwind (Grant the HTH step. Skipping the HTH step and moving and Brady 1975, Grant 1976, Phelan and Baker 1990) directly to CAB occurs at a low frequency (0.23) in and is associated with female acceptance, probably P. pyrusana males. The mating sequence after the Þrst because of some olfactory discrimination process two or three steps is highly stereotypic because the (Grant 1976) during contact between female anten- conditional probability between nonalternative steps nae and the maleÕs wing glands (Grant and Brady is 1.0. This suggests that once a male starts the mating 1975). There is, however, no report of functional wing sequence, the rest of the steps will most likely follow. glands in C. rosaceana or P. pyrusana (Birch and Hefetz Similar kinds of behavior have been reported for 1987, Horak 1991), suggesting that in P. pyrusana a G. molesta (Baker and Carde´ 1979) and C. pomonella different mechanism might be involved in HTH con- (Castrovillo and Carde´ 1980). However, unlike tact behavior. G. molesta (Castrovillo and Carde´ 1980), there were Figure 2A and B shows mating sequence ethograms no additional cues observed within the courtship be- for males of C. rosaceana and P. pyrusana, respectively. havior sequences that were necessary for successful Both leafroller species perform six observable, dis- mating in C. rosaceana and P. pyrusana. crete, and homogeneous steps: WFW to mating In C. rosaceana, immediately after FC, the male (MAT) (Fig. 1L). In Fig. 2, the primary mating be- havior sequence is shown by the bold sold line, slightly CAB (Fig. 1I) and moves toward the femaleÕs terminalia. The maleÕs hair pencils were extended whereas the secondary sequence is shown by a dashed Њ line. Most C. rosaceana males complete only Þve of six in a wider angle, up to 180 . This maneuver always steps, the primary sequence being WFW-FC-CAB- occurred, regardless of the structures encountered in genital engagement (GE) (Fig. 1K)-MAT. The alter- FC, and was required for genital engagement native steps (e.g., male next to female in C. rosaceana; (Fig. 2A). Sometimes, the male positioned himself Fig. 1I) occur at relatively low frequencies (Յ0.03 or next to the female (Fig. 1H, MNF) (also observed in C. pomonella by Castrovillo and Carde´ 1980) and then quickly maneuvered trying to engage the femaleÕs terminalia, i.e., make a copulation attempt (Fig. 1K). In P. pyrusana, the male, after FC, most frequently moved to make HTH contact. The P. pyrusana male then quickly CAB and made a copulation attempt. In both species, male and female genitalia were partially exposed during the copulation attempt (Fig. 1K). Dur- ing the copulation attempt, the male seemed to retain contact with one antenna on the femaleÕs body. In P. pyrusana, the HTH step could help in avoiding interspeciÞc approaches that might lead to incompat- ible mating between the species. If the maleÕs movement was quick, and the female terminalia were within the maleÕs range, copulation was usually successful (Fig. 1L). Studying C. fumi- ferana courtship behavior, Palaniswamy et al. (1979) also found that, if males maneuvered quickly to engage the female genitalia, and the female remained station- Fig. 2. Ethogram for those encounters that resulted in ary, mating was more likely. In P. pyrusana, males successful mating by males of C. rosaceana (n ϭ 31) (A) or usually reacted quickly and contacted the female gen- ϭ P. pyrusana (n 30) (B). Abbreviations indicate the differ- italia (sometimes by an extreme curving of their ab- ent steps observed within the sequence: wing fanning while walking (WFW); Þrst contact (FC); head-to-head (HTH), domen) while maintaining the HTH position. Copu- in P. pyrusana only; male next to female (MNF); curved lation attempts seemed to be an automatic response abdomen (CAB); genitalia engagement (GE); and mating after FC with some part of the femaleÕs body or HTH (MAT). in both C. rosaceana and P. pyrusana. 622 ANNALS OF THE ENTOMOLOGICAL SOCIETY OF AMERICA Vol. 99, no. 3

Table 3. Number and percentage (in parentheses) of female C. rosaceana responding in a particular manner after first contact made by a male

Abdomen Matinga Walk away Jump away Turn around Stationary Total elevated Successful 20 (64.5) 0 3 (9.7) 0 8 (25.8) 31 (100) Unsuccessful 56 (71.8) 4 (5.1) 10 (12.8) 1 (1.3) 7 (9) 78 Total 76 (69.7) 4 (3.7) 13 (11.9) 1 (0.9) 15 (13.8) 109 (100)

a Walk away, female takes at least one step away from the approaching male in any direction (usually forward); jump away, as in walk away but jumping; turn around, the female stays in place but makes a circle around the male; abdomen elevated, the female elevates her abdomen, making it unreachable by males; and stationary, female stays still in place during copulation attempt.

The mating sequence of C. rosaceana best matches Copulation depended on female response after FC the simple courtship behavior model presented by in C. rosaceana (␹2 ϭ 81.2, P Ͻ 0.001) and P. pyrusana Phelan and Baker (1990), i.e., a sequence where the (␹2 ϭ 173.4, P Ͻ 0.001) and was more likely when the male, after locating and contacting a calling female, female remained stationary (Tables 3 and 4). How- simply attempts copulation. Similar simple stereo- ever, some males were able to mate even with a female typed sequences have been observed in other Tortri- whose initial behavior was to escape, i.e., apparently cidae (Palaniswamy et al. 1979, Castrovillo and Carde´ showing some initial form of rejection. In these cases, 1980, Shimizu and Tamaki 1980). However, the se- the persistent male either walked away a short dis- quence in P. pyrusana resembles an interactive court- tance or performed WFW in circles, and then either ship (Phelan and Baker 1990), where after the maleÕs rested (frequently cleaning their antennae at this FC with the female there is an additional HTH contact time) or again initiated the mating sequence by ap- before copulation is attempted. proaching the female. This behavior is similar to re- Courtship sequences often did not result in suc- ports for other Lepidoptera (Baker and Carde´ 1979, cessful mating in C. rosaceana and P. pyrusana, where Haynes and Birch 1984) when initial copulatory at- unsuccessful mating was even more common. Females tempts were unsuccessful in sequences that eventu- of C. rosaceana and P. pyrusana escaped by walking ally ended in mating. away (70 and 66%, respectively), turning around (12 Mating (copulation) success also was signiÞcantly and 14%), or jumping away (4 and 6%) (Tables 3 and dependent on the female body part Þrst contacted by 4). Failure of the male to engage the female genitalia males of both species (C. rosaceana, ␹2 ϭ 144.2, P Ͻ also can occur because a copulation attempt was made 0.001; and P. pyrusana, ␹2 ϭ 263.4, P Ͻ 0.001), which, in the wrong direction (i.e., away from the female) or in turn, was dependent on the female wing position because the male was too far from the femaleÕs ter- (elevated or resting) (C. rosaceana, ␹2 ϭ 43.9, P Ͻ minalia (Fig. 1M). Under laboratory conditions, i.e., 0.001; and P. pyrusana, ␹2 ϭ 103.9, P Ͻ 0.001) (Tables during the relatively short time (Ϸ30 min) a couple 1 and 2). In our study, one C. rosaceana male at- was together in the mating arena, most of the ap- tempted up to 27 copulation attempts before success- proaches in C. rosaceana (71.6%) and P. pyrusana fully engaging the female genitalia (Fig. 1K). After (79.5%) resulted in no mating. This observation con- genital engagement, males turned around (heading trasts with data from Knight and Turner (1998) where the opposite position) and the couple assumed an 85% of the P. pyrusana couples mated when paired for end-to-end position (Fig. 1L). Male hair pencils cov- 24 h in small (30-ml) vials. However, unsuccessful ered the female terminalia during this position. Oc- mating sequences have been reported in courtship casionally in C. rosaceana, males made copulation at- studies of G. molesta (Baker and Carde´ 1979), C. fumi- tempts toward the wrong direction, were too far from ferana (Palaniswamy et al. 1979), and C. pomonella the abdomen, or at a different height (Fig. 1M), again (Castrovillo and Carde´ 1980). Because courtship suggesting that the copulation attempt is a reßex ac- behavior is a mechanism to select sexual partners tion triggered by key contacts, i.e., FC in C. rosaceana (Alexander et al. 1997), we hypothesize that responses and HTH in P. pyrusana. resulting in an unsuccessful mating (assumed to be Based on these data, the female-produced sex pher- rejection) validate this mechanism. omone (calling) is the only apparent trigger leading to

Table 4. Number and percentage (in parentheses) of female P. pyrusana responding in a particular manner after first contact made by a male

Abdomen Matinga Walk away Jump away Turn around Stationary Total elevated Successful 19 (63.34) 0 0 1 (3.33) 10 (33.33) 30 (100) Unsuccessful 78 (67.2) 9 (7.8) 20 (17.2) 0 9 (7.8) 116 Total 97 (66.4) 9 (6.2) 20 (13.7) 1 (0.7) 19 (13) 146 (100)

Walk away, female takes at least one step away from the approaching male in any direction (usually forward); jump away, as in walk away but jumping; turn around, the female stays in place but makes a circle around the male; abdomen elevated, the female elevates her abdomen, making it unreachable by males; and stationary, female stays still in place during copulation attempt. May 2006 CURKOVIC ET AL.: COURTSHIP BEHAVIOR OF C. rosaceana AND P. pyrusana 623

FC in C. rosaceana and P. pyrusana. Such a courtship Curkovic, T. 2004. Behavioral responses of Choristoneura behavior should be compatible with a pheromone- rosaceana (Harris) and Pandemis pyrusana Kearfott males based attracticide technique because it would likely to attracticide sources. Ph.D. dissertation, Washington result in male contact with the attracticide source, be State University, Pullman, WA. it a lethal or sublethal event (Curkovic and Brunner Curkovic, T., and J. F. Brunner. 2003. Assessment of an 2005). This is further supported by observations we attracticide formulation to control Cydia pomonella (L.) (Lepidoptera: Tortricidae) in apple orchards in Wash- have made, and that will be the subject of another ington State, USA. Agric. Te´cnica (Chile) 63: 231Ð239. article, of males of both species making FC and cop- Curkovic, T., and J. F. Brunner. 2005. Residual and sub- ulatory attempts with baited lures and attracticide lethal effects of an attracticide formulation on Choristo- formulations loaded with the species-speciÞc phero- neura rosaceana (Harris), Pandemis pyrusana Kearfott, mone blend used as sources in wind tunnel and Þeld and Cydia pomonella (L.) males (Lepidoptera: Tortrici- assays. dae). Crop Prot. 24: 637Ð641. Delisle, J. 1995. Effect of male and female age on the mating Acknowledgments success of the obliquebanded leafroller, Choristoneura rosaceana (Lepidoptera: Tortricidae) under different We appreciate assistance from Phillip Kirsch and Darek ecological conditions. J. Behav. 8: 781Ð799. Czokajlo (Integrated Pest Management Technologies, Port- Evenden, M. 1998. Semiochemical-based disruption of land, OR) and Kathy Pierre and Mike Doerr (Tree Fruit mate-Þnding behavior in Choristoneura rosaceana (Har- Research and Extension Center, Washington State Univer- ris) and (Robinson) (Lepidoptera: sity) in supporting and conducting different aspects of Tortricidae) in apple orchards. Ph.D. this project. We acknowledge the assistance of Richard dissertation, Simon Fraser University, Vancouver, British Alldredge (Department of Statistics, Washington State Uni- Columbia, Canada. versity) for statistical advice and guidance. This research was Fagen, R. M., and D. Y. Young. 1978. Temporal patterns of partially supported by Agricultural Research Center, Wash- behaviors: durations, intervals, latencies, and sequences, ington State University, Pullman, WA. We appreciate support pp. 100Ð107. In P. W. Colgan [ed.], Quantitative ethology. from the Washington Tree Fruit Research Commission and Wiley, Kingston, Ontario, Canada. from the Washington Commission on Pesticide Registration Grant, C. G. 1976. Female coyness and receptivity during for partial funding of this research. courtship in Plodia interpunctella (Lepidoptera: Pyrali- dae). Can. Entomol. 108: 975Ð979. Grant, C. G. 1987. Copulatory behavior of budworm, References Cited Choristoneura fumiferana (Lepidoptera: Tortricidae): ex- Alexander, R. D., D. C. Marshall, and J. R. Cooley. 1997. perimental analysis of the role of sex pheromone and Evolutionary perspectives in insect mating, pp. 4Ð31. In associated stimuli. Ann. Entomol. Soc. Am. 80: 78Ð88. J. C. Choe and B. J. Crespi [eds.], Mating systems in Grant, C. G., and U. Brady. 1975. Courtship behavior of insects and arachnids. Cambridge University Press, Cam- phycitid moths. I. Comparison of Plodia interpunctella bridge, United Kingdom. and Cadra cautella and role of male scent glands. Can. J. Andersson, M., and Y. Iwasa. 1996. Sexual selection. Trends Zool. 53: 813Ð826. Ecol. Evol. 11: 53Ð58. Haynes, K. F., and M. C. Birch. 1984. Mate-locating and Baker, T. C., and R. T. Carde´. 1979. Courtship behavior of courtship behaviors of the artichoke plume moth, oriental fruit moth (Grapholita molesta): experimental Platyptilia carduidactyla (Lepidoptera: Pterophoridae). analysis and considerations of the role of sexual selection Environ. Entomol. 13: 399Ð408. in the evolution of courtship pheromones in the Lepi- Hofer, D., and M. Angst. 1995. Control of pink bollworm in ᭨ doptera. Ann. Entomol. Soc. Am. 73: 100Ð105. cotton with Sirene , a novel sprayable attract & kill Beers, E. H., J. F. Brunner, M. Willett, and G. Warner. 1993. formulation. In Proceedings/1995 National Cotton Amer- Orchard pest management: a resource book for the Pa- ican Council 2: 68Ð69. ciÞc Northwest. Good Fruit Grower, Yakima, WA. Horak, M. 1991. Morphology, pp. 1Ð22. In L. van der Geest Birch, M., and A. Hefetz. 1987. Extrusible organs in male and H. Evenhuis [eds.], Tortricid pests: their biologies, moths and their role in courtship behavior. Bull. Entomol. natural enemies, and control. Elsevier, Amsterdam, The Soc. Am. 13: 222Ð229. Netherlands. Brunner, J. F. 1994. Pest management of leafrollers in Knight, A. L., and J. E. Turner. 1998. Sexual biology of Washington apple orchards, pp. 54Ð67. In Proceedings Pandemis pyrusana (Lepidoptera: Tortricidae) under lab- of the Washington State Horticultural Association 89th oratory conditions. J. Entomol. Soc. Br. Columbia 95: Annual Meeting, 5Ð7 December, 1993, Yakima, WA. 89Ð94. Wash. State Hort. Assoc., Wenatchee, WA. Krupke, C. H. 1999. Behavioral response of male codling Cade, W. H. 1985. Insect mating and courtship behaviour. moth (Cydia pomonella (L.)) to a semiochemical-based Comp. Insect Physiol. Biochem. Pharmacol. 9: 591Ð619. attract and kill management strategy. M.S. thesis, Simon Castrovillo, P. J., and R. T. Carde´. 1980. Male codling moth Fraser University, Vancouver, British Columbia, Canada. (Laspeyresia pomonella) orientation to visual cues in the Lingren, P. D., J. R. Raulston, A. N. Sparks, and W. W. Wolf. presence of pheromones and sequences of courtship be- 1982. Insect monitoring technology for evaluation of haviors. Ann. Entomol. Soc. Am. 72: 173Ð188. suppression via pheromone systems, pp. 171Ð193. In Charmillot, P. J., D. Pasquier, A. Salco, and D. Hofer. 1996. A. F. Kydonieus and M. Beroza [eds.], Insect suppression Essais de lutte contre le carpocapse Cydia pomonella L. with controlled release pheromone systems. CRC, Boca par un proce´de´ attracticide. Rev. Suisse Vitic. Arboric. Raton, FL. Hortic. 69: 431Ð439. Matsuda, R. 1976. Morphology and evolution of the insect Charmillot, P. J., D. Hofer, and D. Pasquier. 2000. Attract abdomen. Pergamon, Elmsford, NY. and kill: a new method for control of the codling moth Palaniswamy, P., W. Seabrook, and R. Ross. 1979. Precop- Cydia pomonella. Entomol. Exp. Appl. 94: 211Ð216. ulatory behavior of males and perception of a potential 624 ANNALS OF THE ENTOMOLOGICAL SOCIETY OF AMERICA Vol. 99, no. 3

male pheromone in spruce budworm, Choristoneura Shorey, H. H., and R. L. Hale. 1965. Mass-rearing of the fumiferana. Ann. Entomol. Soc. Am. 72: 544Ð551. larvae of nine noctuid species on a simple artiÞcial me- Phelan, P. L., and T. C. Baker. 1990. Comparative study of dium. J. Econ. Entomol. 58: 522Ð524. courtship in twelve phycitinae moths (Lepidoptera: Silverstein, R. M. 1981. Pheromones: background and po- Pyralidae). J. Insect Behav. 3: 303Ð326. tential for use in insect pest control. Science (Wash., DC) SAS Institute. 2002. JMP statistics and graphics guide, ver- 213: 1326Ð1332. sion 5th ed. SAS Institute, Cary, NC. Shimizu, K., and Y. Tamaki. 1980. Releasers of male copu- latory attempt in the smaller tea tortrix moth (Lepidop- tera: Tortricidae). Appl. Entomol. Zool. 15: 140Ð150. Received 20 April 2005; accepted 6 January 2006.