Graphium agamemnon Linnaeus (Lepidoptera: Papilionidae), a pest of soursop (Annona muricata Linnaeus), in Vietnam: Biology and a novel method of control

Few butterflies are pests of economic significance, but some may be locally destructive, such as the papilionid Graphium agamemnon Linnaeus, which is known to feed on the commercially important soursop (Annona muricata Linnaeus) in Vietnam. This paper documents the life history and ecology of G. agamemnon and investigates commonly used control measures in south‐east Vietnam. A novel method of controlling G. agamemnon infestation is described. If soursop basal rootstock (Annona glabra Linnaeus) is encouraged to shoot during times of peak butterfly activity, ovipositing G. agamemnon females are preferentially attracted to the new growth where the resulting early stages may be easily detected and removed by hand.     

Aristolochiaceae‐ and Asteraceae‐feeding by larvae of Papilio xuthus L. (Lepidoptera: Papilionidae) in Japan: A review

Our recent observations of Aristolochiaceae‐ and Asteraceae‐feeding by larvae of Papilio xuthus L. (Lepidoptera: Papilionidae), which is generally a typical Rutaceae‐feeding swallowtail, inspired us to survey published works describing its host range and aspects of its chemical ecology. Papilio xuthus larvae have been observed feeding on a total of 22 plant species other than members of Rutaceae, including those of Asarum (Aristolochiaceae) and Cosmos (Asteraceae). Most observation records and our current study indicated that Aristolochiaceae‐feeding by P. xuthus larvae was not due to oviposition error, but to larval movement to Asarum from adjacent rutaceous hosts after they had become unsustaining. Many larvae developed on Asarum to further stadia but we confirmed that some did not, indicating that Asarum was unsuitable for some individuals. According to previous and current observations, P. xuthus females oviposit directly on Cosmos and their larvae can develop to adults although, again, their performance on these plants is not always favorable. Host choice by swallowtail butterflies is determined both at the egg‐laying and larval‐feeding stages. Although adult P. xuthus use a mixture of unique secondary metabolites as their host‐location cue, larvae use primary nutrients as their major phagostimulants. Larval feeding on Asarum could suggest a reversion triggered by vestigial chemosensitivity to ancestral olfactory and/or gustatory cues, because several major clades of Papilionidae feed on Aristolochiaceae. Further studies on the phytochemical/chemosensory bases for these associations are needed if we are to understand the evolutionary pathway of host selection in P. xuthus, as indicated by these relatively unusual host‐seeking behaviors.     

Influence of target plant density on herbivorous insect oviposition choice: Ambrosia artemisiifolia L. (Asteraceae) and Zygogramma suturalis F. (Coleoptera: Chrysomelidae)

Zygogramma suturalis F. has been introduced to Russia for the biological control of the common ragweed Ambrosia artemisiifolia L. The functional response of Z. suturalis to the density of the target plant was studied at two levels: between plants and between 0.1 m² sampling plots. The number of Z. suturalis eggs per unit of plant weight was almost independent of plant weight, indicating that a functional response between plants is absent. However, tall and intermediate height plants received more eggs per phytomass unit than short plants. Between plots, correlation analysis showed that absolute Z. suturalis egg density is positively dependent on the ragweed density. Experiments showed that the locomotor activity of ovipositing females decreased when on the ragweed, suggesting orthokinesis. The number of leaf beetle eggs per unit of ragweed weight was negatively correlated with host plant density in May‐June, when the majority of eggs are laid, but was positively correlated in July and loosely, or not significantly, correlated in August. Seasonal changes in the functional response of a herbivorous insect to host plant population density have not been reported previously. A negative functional response of a herbivorous insect to target plant density can be a serious obstacle to the biological control of weeds.     

Effects of plant odor on oviposition by the black swallowtail butterfly,Papilio polyxenes (Lepidoptera: Papilionidae)

Black swallowtail females laid more eggs on plant models treated with contact stimulants and volatiles from carrot leaves than on models treated only with contact stimulants. The volatiles enhanced landing rates and females alighted more frequently on artificial leaves treated with host volatiles than on adjacent control leaves. Volatiles from cabbage, a nonhost, inhibited landing rates on artificial leaves treated with carrot contact stimulants. Examination of antennae revealed two major types of sensilla, believed to be olfactory in function. Electroantennogram preparations responded more strongly to carrot volatiles than to cabbage volatiles and several shared responses at particular retention times to carrot volatile components eluting from a gas chromatograph. Our results are consistent with a long-standing hypothesis that behavioral responses to essential oil components characteristic of the larval food plants have facilitated host shifts in the genus Papilio.     

New evidence on the systematic and phylogenetic position of Parides burchellanus (Lepidoptera: Papilionidae)

Parides burchellanus is considered a rare and threatened swallowtail species restricted to central Brazil. It shows considerable morphological similarity to Parides panthonus jaguarae, with which it shares both geographical range and larval host plant. At present, P. burchellanus and P. panthonus are believed to be distinct species, based on minor differences in male genitalia. In this study, the phylogenetic and systematic position of P. burchellanus in relation to three subspecies of P. panthonus (P. p. jaguarae, P. p. lysimachus and P. p. aglaope) was evaluated using molecular evidence: the complete sequence of the mtDNA genes COI and COII and of the nuclear gene EF‐1α (c. 3300 bp). In addition, the informativeness of the ‘barcode’ region next to the 5′ end of COI (c. 650 bp) was evaluated for delimiting these taxa. Individual analysis by neighbour‐joining, using Kimura 2‐parameter distance model, and by maximum parsimony showed that P. p. jaguarae + P. p. lysimachus + P. p. aglaope + P. burchellanus form a strongly supported monophyletic clade, and all molecular regions consistently recovered P. p. jaguarae and P. burchellanus as sister species. The genetic divergence among the subspecies of P. panthonus and P. burchellanus is equivalent to the divergence among conspecifics of other species of Parides, and smaller than the interspecific divergence among different sister species of this genus. The results support the proposal that P. p. jaguarae and P. burchellanus are likely to be synonymous, and suggest that P. burchellanus can be considered conspecific with P. panthonus. The taxonomic classification of P. burchellanus should be revised on the basis of the molecular data.     

Behaviour of roach (Rutilus rutilus L.) altered by Ligula intestinalis (Cestoda: Pseudophyllidea): a field demonstration

1. We studied the influence of a cestode parasite, the tapeworm Ligula intestinalis (L.) on roach ( Rutilus rutilus L.) spatial occupancy in a French reservoir (Lake Pareloup, South-west of France).
2. Fish host age, habitat use and parasite occurrence and abundance were determined during a 1 year cycle using monthly gill-net catches. Multivariate analysis [generalized linear models (GLIM)], revealed significant relationships ( P  < 0.05) between roach age, its spatial occupancy and parasite occurrence and abundance.
3. Three-year-old roach were found to be heavily parasitized and their location toward the bank was significantly linked to parasite occurrence and abundance. Parasitized fish, considering both parasite occurrence and abundance, tended to occur close to the bank between July and December. On the contrary, between January and June no significant relationship was found.
4. These behavioural changes induced by the parasite may increase piscivorous bird encounter rate and predation efficiency on parasitized roach and therefore facilitate completion of the parasite's life cycle.     

Field observations of mating,oviposition, and feeding behavior ofAnticarsia gemmatalis (Lepidoptera: Noctuidae) in a soybean field

The temporal occurrence and frequency of mating, oviposition, and feeding of wild velvetbean caterpillar moths, Anticarsia gemmatalis,in a soybean field (Glycine max)were documented. Mating occurred predominately during the first 4 h after sunset and primarily on leaflet bottoms. Oviposition was concentrated within the first 6 hr after sunset. Eggs were laid singly, and in areas of high trichome density, on leaflets, pulvini, and petioles. Feeding occurred primarily at night, with most males feeding during the first half of the night and females during the second half. Males and females shared some food sites but others were visited strictly by males.     

The influence of a shortage of hosts on the specificity of oviposition behaviour in species of Dacus (Diptera, Tephritidae)

ABSTRACT. When deprived of their preferred hosts for up to 16 days prior to behaviour assays, three relatively specialized tephritid flies, D. cacuminatus (Hering), D. cucumis French and D. jarvisi (Tryon), retain strong preferences for their particular hosts. Moreover, in the absence of the preferred hosts, D. cacuminatus , and to a lesser extent D. cucumis , will not accept fruits that are outside their normal host range. D. jarvisi readily accepts other fruits in the absence of its preferred host, Planchonia careya , but in common with the other two shows no increase in the number of eggs laid with increasing periods of deprivation. None of these species accumulate oocytes when deprived of fruits.
In contrast, the highly polyphagous D. tryoni Frogg. lays more eggs and oviposits readily into a previously unacceptable fruit after 4 days without access to hosts. This change in behaviour is associated with a marked increase in the number of mature eggs carried by females.
These results suggest an important difference between the generalist and more specialized species in the physiological control of oocyte maturation. In D. tryoni there appears to be no inhibition of oocyte development once the primary follicle has matured, whereas in the other species each ovariole contains no more than one mature egg.
In D. tryoni , the change in behaviour which accompanies this increase in egg load, may influence its propensity to accept unusual fruits, and may help to explain its rapid acceptance of most cultivated fruits introduced to Australia.     

Oviposition preference of swallowtail butterfly,Papilio polytes (Lepidoptera: Papilionidae) on four Rutaceae (Sapindales) host plant species

Abstract Oviposition preference and egg deposition site selection by the butterfly, Papilio polytes L. (Lepidoptera: Papilionidae) on four rutaceous host plants, Citrus aurantofolia (Christm.) Swing., Citrus hystrix DC., Citrus reticulata Blanco, and Murraya koenigii (L.) Sprengel, were assessed in field cages measuring 2 × 2 × 2 m. Simultaneous two-choice and four-choice oviposition tests of whole host plants were conducted. The mean total number of eggs laid per plant on C. reticulata in the two-choice test was significantly higher (P < 0.01) than those on C. aurantifolia, C. hystrix, and M. koenigii. Among the three other host plants, C. aurantifolia was preferred over C. hystrix, and M. koenigii (P < 0.01) and C. hystrix was preferred over M. koenigii (P < 0.01). In the four-choice test, C. reticulata was highly preferred and significantly different from C. hystrix and M. koenigii. However, no oviposition preference was detected with C. aurantifolia. Among the various plant parts in the two- and four-choice tests, eggs on leaves of each plant were the highest, followed by numbers on stems, and negligible numbers on pots. These numbers on leaves of C. reticulata and C. aurantifolia were not significantly different (P > 0.05), but differed significantly (P < 0.01) from those on leaves of C. hystrix and M. koenigii. The quantitative trend of egg-laying on stems was very similar to that observed for the leaves. Papilio polytes showed strong preference to lay eggs on the underside of leaves of all host plants than on the upper side or on the petiole. More eggs were laid on the upper side of each host plant than on its petiole. The four host plants in descending order of preference were C. reticulata≥C. aurantifolia > C. hystrix > M. koenigii. Although M. koenigii was the least preferred, it has the potential to serve as an alternative host plant for P. polytes which can be manipulated when necessary, to alleviate the infestation of this pest to the citrus industry.     

Phenology of Parasetigena silvestris (Diptera: Tachinidae), gypsy moth (Lymantria dispar) (Lepidoptera: Lymantriidae) larval parasitoid and its efficiency for parasitisation

Parasetigena silvestris is a univoltine, solitary, larval endoparasitoid which lays its eggs on the surface of gypsy moth larvae. Field collection of the host larvae (2nd through 5th instar) from an artificially established gypsy moth population were made to compare stage specific parasitism between larvae without and with P. silvestris tachinid eggs. The tachinid oviposition rate detected was highest in second instar larvae, and then decreased as larvae developed toward full maturity. The opposite was true for tachinid parasitoid emergence which had no emergence from second through third host instar larvae. Fourth instar gypsy moth larvae, however, experienced significantly higher parasitism by P. silvestris in the larvae with eggs than those without the eggs. The braconid wasp Cotesia melanoscelus caused significantly higher parasitism in early instar larvae with P. silvestris eggs than in those without the eggs. The tachinid prefers to lay more eggs on parasitised larvae by the braconid even though the braconid is a superior competitor to the fly during multiparasitism. Factors influencing parasitism rates by P. silvestris such as host-parasitoid synchronisation and the multiparasitism interaction with C. melanoscelus are discussed.     

豚草生育期和被利用状态对广聚萤叶甲产卵选择的影响

【背景】植食性昆虫对产卵场所的选择行为受多种因素的影响,其中寄主植物的发育阶段和被同种其他个体利用程度是影响其产卵选择的重要因素之一。【方法】采用野外罩笼的选择性试验,观察了广聚萤叶甲成虫对不同生长发育阶段、不同被取食程度、不同落卵量的豚草植株的产卵选择行为,分析产卵选择频次,用Cox比例风险模型拟合识别期以估计产卵选择偏好性。【结果】开花期豚草被选择产卵的风险(瞬间概率)仅为生长期的16.5%,苗期豚草被选择产卵的风险为生长期的34.1%;成虫对3种被食程度豚草的产卵选择频次之间存在显著差异(n=20,P<0.01),在3级被食程度豚草上产卵次数最多(12次),而在5级被食豚草上产卵次数最少(2次),表明成虫明显偏好将卵产于已被中等程度取食的植株上;成虫对不同落卵量植株(0、4、8个.株-1)未表现出显著的产卵偏好,对不同密度(高、低)斑块的豚草的产卵选择亦无显著差异。【结论与意义】豚草生育期和被取食程度影响广聚萤叶甲雌虫的产卵选择,而植株上的落卵量和豚草密度对产卵选择没有影响。     

水稻矮缩病毒对黑尾叶蝉取食及产卵偏好性的影响

水稻矮缩病毒（Rice dwarf virus, RDV）是水稻普通矮缩病（Rice dwarf disease）的病原,主要依赖黑尾叶蝉Nephotettix cincticeps经卵以持久增殖方式传播。本研究采用室内试验观测了带毒与无毒的黑尾叶蝉在健康及感病水稻间的取食、产卵选择趋性。取食偏好性试验发现,无毒叶蝉对感病水稻趋性更强,从观测的第8小时开始达显著差异水平;带毒叶蝉则对健康水稻趋性更强,在观测的第24小时开始达到显著差异水平,表明RDV侵染水稻会引起黑尾叶蝉取食偏好性的改变。产卵偏好性试验发现无毒及带毒黑尾叶蝉在健康及感病水稻间3个观测指标（每植株卵块数、每卵块的卵量及每植株上的总卵量）均无显著差异,表明RDV侵染水稻对黑尾叶蝉产卵选择偏好性无显著影响。本文初步明确RDV对黑尾叶蝉取食和产卵偏好性的影响,为揭示介体昆虫-病毒-寄主植物三者之间的互作机制提供佐证。     

Suitability of Eucalyptus and Corymbia for Mnesampela privata (Guenée) (Lepidoptera: Geometridae) larvae

Abstract 1 Mnesampela privata (Guenée) has a host list of 40 Eucalyptus and at least one Corymbia species. Larval survival and performance was studied on 19 species to investigate how certain leaf traits influence the suitability of different species. 2 After 7 days, survival on Eucalyptus aggregata and Eucalyptus camphora is greater than 70% even though the toughness of leaves is 0.15–0.19 mg/mm². However, after the same time, survival on genotypes of Eucalyptus melliodora and Eucalyptus sideroxylon was less than 60%, or even 0%, even though the toughness of some leaves was as low as 0.11 mg/mm². An unmeasured allelochemical, rather than toughness, may reduce survival on these species. 3 Dry weights of first‐instar larvae were negatively correlated with leaf toughness for 13 of the species studied. Species that produced the heaviest first‐instar larvae were not the same hosts that produced the heaviest second‐instar larvae. 4 Dry weights of female pupae were negatively correlated with total oil content for five of the species studied. 5 Larvae exhibit age‐related changes in feeding behaviour. Neonates skeletonize leaves (avoid leaf veins and oil glands) and post‐third‐instar larvae ingest whole leaf fragments (consume small leaf veins and oil glands). These findings suggest that neonates are sensitive to high leaf toughness and non‐oil plant secondary metabolites whereas older larvae are less sensitive to high leaf toughness and are likely to become larger adults on hosts with lower oil contents.     

Comparison of oviposition behavior of a solitary and a gregarious parasitoid (Hymenoptera: Mymaridae)

Anaphes victus Huber andAnaphes listronoti Huber (Hymenoptera: Mymaridae) are respectively solitary and gregarious egg parasitoids of the carrot weevil,Listronotus oregonensis (LeConte) (Coleoptera: Curculionidae). We made detailed ethograms of the oviposition behavior on unparasitized and parasitized hosts for the two species. We then compared the behavior of virgin and mated females for the oviposition of male and female progenies. The two species did not always oviposit after insertion of the ovipositor, but these punctures without oviposition could be readily differentiated from oviposition.A. victus oviposited only once by puncture, whileA. listronoti deposited one to three eggs during the same sequence. The variability of the duration of the various components was generally lower for a given female than between females. Two components, the abdominal vibrations and the pause, were significantly shorter in ovipositions that resulted in male progency for the two species. However, an important overlap in duration prevents using these differences to sex the progeny at oviposition. Virgin females of both species, although capable of producing only males, exhibited both behaviors. Parasitized hosts were recognized through internal and external markings that were used in host discrimination.     

光周期变化对毛健夜蛾交配和产卵的影响

【目的】毛健夜蛾Brithys crini(Fabricius)可为害葱莲Zephyranthes candida等石蒜科绿化植物,前期研究表明不同光周期对其交配和产卵节律行为及交配率和产卵量均有显著影响。本实验期望探明间歇光照等复杂光照条件对毛健夜蛾交配和产卵的影响。【方法】在光照培养箱条件下(光源为白色日光灯,光照强度约为500 lx),观察了间歇光照长度(20,10,5,1和0 min)、暗期位点(D10:00-22:00,D12:00-24:00,D14:00-02:00和D16:00-04:00)和非24 h光暗循环(4L∶4D,8L∶8D,24L∶24D和48L∶48D)3种光照条件下毛键夜蛾成虫交配及产卵行为。【结果】间歇光照长度为20,10,5,1和0 min时,成虫交配数分别为0,3,10,14和11对,配对数分别为25,29,31,39和26对;间歇光照长度为20和10 min时,交配数与对照组差异显著;10,5,1和0 min时已交配单雌产卵量差异不显著(分别为354.67,322.30,339.57和310.45粒)。暗期位点为D10:00-22:00,D12:00-24:00,D14:00-02:00和D16:00-04:00时,成虫交配数分别为13,18,15和12对,配对数分别为16,19,17和16对,交配数差异不显著;已交配单雌产卵量差异不显著(分别为516.15,527.28,495.53和458.50粒);交配起始时间、交配高峰时间和产卵起始时间、产卵高峰因暗期位点不同而异。非24 h光暗循环(4L∶4D,8L∶8D,24L∶24D和48L∶48D)条件下成虫交配数分别为16,15,14和14对,配对数分别为18,16,14和16对,交配数差异不显著;已交配单雌产卵量差异显著(分别为590.56,559.67,497.21和419.29粒)。【结论】这些结果显示毛健夜蛾交配和产卵行为主要发生在暗期,暗期短于40 min时不能发生交配行为,暗期位点和长度对交配和产卵行为有影响。     

Effect of sorghum resistant to Stenodiplosis sorghicola (Coquillett) (Diptera: Cecidomyiidae) on oviposition and development of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae)

Abstract Helicoverpa armigera oviposition preference for, and larval development on sorghum hybrids with differing resistance to sorghum midge, Stenodiplosis sorghicola , were investigated. When H. armigera larvae were fed seed of resistant and susceptible hybrids in the laboratory there were no differences in larval and pupal sizes or the rate of development. The same result was recorded when larvae fed on panicles on plants in a glasshouse. On some sampling occasions, significantly more eggs were laid on panicles of resistant hybrids in the field. This occurred when plants were in plots and also in a mixed planting. Midge-resistance status did not affect levels of egg parasitism. In a field study using recombinant inbred lines between a midge-resistant and a midge-susceptible line, no relationship was found between level of resistance and oviposition of H. armigera . We conclude that, although midge-resistant hybrids are sometimes preferred for oviposition by H. armigera, the resistance per se does not determine this preference. Egg survival, larval survival, development and resultant damage are not significantly affected by the midge-resistance status of the host.     

广聚萤叶甲成虫取食经历对后续 产卵寄主选择的影响

【背景】取食经历对植食性昆虫的寄主选择行为具有较大影响,影响天敌昆虫寄主专一性测定的设计和结果解释。【方法】采用选择性试验,观察了入侵豚草的重要天敌——广聚萤叶甲成虫羽化后取食不同植物对其后续产卵寄主选择的影响。【结果】与取食豚草的试虫相比,有取食三裂叶豚草、苍耳或菊芋经历的成虫选择苍耳产卵的频次增加,不再对豚草表现出明显的选择偏好性。对产卵识别期的Cox模型分析结果表明,成虫早期取食不同植物,对后续产卵选择有显著影响,成虫羽化后如果先取食豚草或三裂叶豚草,则选择苍耳产卵的倾向显著低于豚草;但如果先取食苍耳、菊芋和农家向日葵,则选择苍耳产卵的倾向与豚草无显著差异。【结论与意义】由此推测,广聚萤叶甲初羽化成虫取食的植物对其后续产卵选择具有较大影响,因而在寄主专一性测定中应关注测试前饲喂的植物种类。     

Oviposition on host plants by a tropical forest grasshopper (Microtylopteryx hebardi: Acrididae)

Abstract. 1. The tropical forest grasshopper Microtylopteryx hebardi Rehn (Orthoptera, Acrididae, Ommatolampinae) oviposits inside leaves or stems of its host plants. This is the first known instance of oviposition inside living plant tissue (rather than in the ground, on top of leaves, or in detritus) for a tropical forest acridid.
2. In understorey secondary forest at La Selva, Costa Rica, M.hebardi females fed on fifteen species of host plants, but oviposited in only four of these.
3. In laboratory choice tests, females showed selectivity for oviposition host plants similar to that inferred from field observations.
4. Plant volume was a better predictor of the number of eggs laid per stem than variables that indicated leaf or stem characteristics of individual plants.
5. Unlike the ovipositor of acridids laying eggs in the ground, that of M.hebardi is equipped with toothed, sclerotized edges, probably used to bore into plant tissue.
6. Endophytic oviposition in M.hebardi may be related to finding host plants in a habitat that is complex, heterogeneous, and rich in plant species.     

Vetiver grass (Vetiveria zizanioides (L.) Nash) as trap plant for Chilo partellus (Swinhoe) (Lepidoptera: Pyralidae) and Busseola fusca (Fuller) (Lepidoptera: Noctuidae)

The preference of lepidopterous stem borer moths to oviposit on certain wild host plants can be exploited in habitat management systems by using those hosts as trap crops. Vetiver grass (Vetiveria zizanioides (L.) Nash) was evaluated for its attractiveness and suitability to the pyralid Chilo partellus (Swinhoe) (Lepidoptera: Pyralidae) and the noctuid Busseola fusca (Fuller) (Lepidoptera: Noctuidae). Two choice tests were conducted in the laboratory and in the greenhouse to determine oviposition choice of C. partellus for maize, Vetiver and rice (Oryza sativa L.), and of B. fusca for Vetiver and maize. C. partellus larval survival was evaluated in green house studies. Results indicated that C. partellus chose Vetiver grass over maize though larval survival on Vetiver was extremely low. B. fusca did not show any host preference.     

Effect of host deprivation on egg quality,egg load,and oviposition in a solitary parasitoid,Chetogena edwardsii (Diptera: Tachinidae)

Solitary parasitoids are limited to laying one egg per host because larvae compete within hosts. If host encounter rate is low, females should not increase the number of eggs/host in response. The tachinid fly, Chetogena edwardsii,was used to evaluate the effect of host deprivation on egg accumulation, oviposition behavior, and egg quality in a solitary parasitoid. Females deprived of hosts for 2– 7 days accumulate about 1 day's supply of eggs. Egg output of deprived females once hosts are restored does not differ from that of control females. Deprived females retain one egg in the uterus where it undergoes embryogenesis. Maggots emerging from retained eggs are more likely to survive in hosts molting in 40 h or less after receipt of an egg than are maggots emerging from eggs fertilized shortly before oviposition. Egg retention is a consequence of host deprivation that permits females to broaden the range of hosts they can exploit to include soon-to-molt hosts and possibly multiply parasitized hosts.