Attraction of newly hatched codling moth larvae (Laspeyresia pomonella) to synthetic stereo-isomers of farnesene

Newly hatched Laspeyresia pomonella larvae were attracted to only two of six synthetic stereo-isomers of the acyclic sesquiterpene farnesene. These were (E,E)-α-farnesene and (Z,E)-α-farnesene which together comprise a natural attractant for the insect. Two other α-isomers and two β-isomers had no influence on larval behaviour. The activity of isomers is correlated with their molecular shape.     

Termination of the facultative diapause in the codling moth, Laspeyresia pomonella (Lepidoptera, Tortricidae)

The abiotic factors regulating the termination of the facultative diapause of the mature larva of the codling moth, Laspeyresia pomonella (L.), are described. The termination of diapause under long-day conditions (LD) is influenced by: (i) the rearing temperature of the larvae during prediapause development, (ii) the duration of the preincubation period, i.e. the time for which the diapausing larvae remain under prediapause rearing conditions, (iii) the reactivating incubation, i.e. the period for which the larvae are chilled, and (iv) the complementary incubation (LD and, except in one experiment, 26°), i.e. the period after the chilling needed for the pupation of the insects. The complementary incubation is distinctly shorter if the prediapause development of the larvae takes place at rearing temperatures below 26°, i.e. 21° or 19°. The latter conditions led to 100% pupae and pupation could be accelerated by prolonging the preincubation period. In larvae reared at 26°, the prolongation of the preincubation period raised the rate of pupation to a maximum of only 56% and also caused higher mortality. On the other hand, diapause was terminated under short-day conditions if the temperature was raised to 26° after a rearing temperature of 19° and a preincubation period of 90 days.

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Beendigung der fakultativen diapause des apfelwicklers, Laspeyresia Pomonella (Lepidoptera, Tortricidae)

Zusammenfassung Es wurde untersucht, welche abiotischen Faktoren die Beendigung der fakultativen Diapause ausgewachsener Apfelwicklerlarven (Laspeyresia pomonella) steuern. Die Beendigung der Diapause unter Langtagbedingungen (LT) wird beeinflusst durch: 1. die Zuchttemperatur der Larven während der Prädiapauseentwicklung; 2. die Dauer der Präinkubation, d.h. die Zeit, während der diapausierende Larven unter Prädiapause-Zuchtbedingungen bleiben; 3. die Reaktivierungs-inkubation, d.h. eine Periode von 70 d, während der die Larven auf 4° gekühlt werden und 4. die Komplementärinkubation (LT und, ausser in einem Experiment, 26°), d.h. die nach der Kühlung bzw. dem Wechsel in der Photoperiode benötigte Zeitdauer bis zur Verpuppung. Die Komplementärinkubation ist deutlich kürzer, wenn die Prädiapauseentwicklung der Larven bei Temperaturen unter 26° stattfindet. Bei 19° verpuppten sich 100% der Larven, wobei der Zeitpunkt der Verpuppung durch die Verlängerung der Präinkubationszeit beschleunigt wurde. Bei Larven, die bei 26° gezüchtet wurden, erreichte die Verpuppungsrate lediglich 56% bei einer relativ langen Präinkubationsdauer, wobei deren Verlängerung auch die Larvenmortalität erhöhte. Nach einer Zuchttemperatur von 19° und einer Präinkubationsdauer von 90 Tagen konnte die Diapause unter Kurztagbedingungen beendet werden, wenn die Temperatur auf 26° erhöht wurde.

     

Circadian control of oviposition in the codling moth, Laspeyresia pomonella, Lepidoptera: Olethreutidae

The oviposition rhythm in Laspeyresia pomonella (L.) is entrained by light-dark cycles and freeruns in continuous light with a period =25.9 hr and in continuous darkness with =21.8 hr. In the laboratory as well as in the field, the median of oviposition occurs on average 2.5 hr before the onset of darkness. The codling moth can adapt quickly to a new light regime. Oviposition was resynchronized with a normal light-dark cycle within 48 hr after freerunning for several days in continuous light.

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Circadiane steuerung der eiablage beim apfelwickler, Laspeyresia pomonella, lepidoptera, olethreutidae

Zusammenfassung Der Eiablagerhythmus von Laspeyresia pomonella (L.) wird von Licht-Dunkel-Zyklen gesteuert und läuft frei im Dauerlicht mit einer Periode =25.9 St. und im Dauerdunkel mit =21.8 St. Im Labor sowie unter natürlichen Bedingungen lag der 50%-Punkt der täglichen Eiablage jeweils 2.5 St. vor dem Beginn der Dunkelheit. Der Apfelwickler kann sich rasch an ein verändertes Lichtregime anpassen. Nach mehreren Tagen Freilauf im Dauerlicht synchronisierte sich der Eiablagerhythmus innerhalb von 48 St. mit einem normalen Licht-Dunkel-Zyklus.

     

Death of Cydia pomonella larvae and damage to apple fruit, after field application of codling moth granulosis virus

In field experiments, larvae of codling moth Cydia pomonella (L.) rarely acquired granulosis virus on hatching from the egg, but picked up most later, on the tree surface. Deposits of virus sprayed in 1.0% w/v skimmed milk did not affect neonate larval behaviour. Larvae died, usually in the first instar, after entering treated fruit, but they frequently entered via the calyx or near the base of the stalk or through cracks in the skin, where little feeding damage by first-and sometimes second-instar larvae was seen.

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Résumé En verger, la pulvérisation d'oeufs de carpocapse avec du virus de la granulose en suspension dans l'eau (additionnée de lait écrémé dilué à 1%) n'a pas modifié la survie des chenilles avant pénétration dans le fruit; par contre la pulvérisation des arbres a provoqué une forte mortalité. Bien que des chenilles consommant des poils et la surface des feuilles aient été observées avant leur pénétration dans le fruit, ce qui aurait pu provoquer leur contamination par le virus, il semble que la contamination létale provienne des fruits seuls.La présence de produit n'a modifié ni le comportement larvaire, ni le taux de pénétration dans les fruits; la mortalité y a lieu ensuite, généralement au premier stade. Dans 74 à 78% des cas, les chenilles ont pénétré dans le fruit par le calice ou près de la base du pédoncule — aucun dégât provenant de larves du premier stade n'y était visible, de même que dans le calice pour les larves du deuxième stade. Par contre, toute pénétration par la surface du fruit était repérable dès le premier stade. Il est possible que la répartition des lieux de pénétration dans le fruit influe sur la létalité due au virus et explique les variations d'efficacité observées en verger. Un système de classification des dégâts, provoqués lors de la pénétration dans le fruit, de chenilles du premier au troisième stade est proposé pour évaluer l'efficacité des essais en verger.

     

The circadian rhythm of sperm release in the codling moth, Cydia pomonella

The release of sperm bundles from testes to the vas deferens is controlled by a circadian clock in several moth species. We investigated the pattern of sperm release in the codling moth, Cydia pomonnella L. (Lepidoptera: Tortricidae). Sperm release in the codling moth follows a two-step rhythm in light-dark cycles: sperm is released from the testis before lights-off, remains in the vas deferens during the dark phase and is transferred to the seminal vesicles after lights-on. This rhythm continues in constant darkness indicating that it has a circadian nature. The release of sperm is asynchronous in moths held in constant light. In contrast to previously investigated moths, constant light has no adverse effects on the male reproductive capacity in the codling moth.     

Differential ovicidal and larvicidal resistance to benzoylureas in the codling moth, Cydia pomonella

French populations of the codling moth Cydia pomonella (L.) (Lepidoptera, Tortricidae), a major pest in apple and pear orchards, have developed resistance to different classes of insecticides including the benzoylurea diflubenzuron, a chitin synthesis inhibitor. Ovicidal tests performed on two susceptible strains and one strain selected for its resistance to diflubenzuron revealed the same order of magnitude in resistance ratios to this compound (30-fold) and two other benzoylureas teflubenzuron and flufenoxuron (22- and 11-fold, respectively). Field rates of these three compounds induced a 45–55% decrease in hatching in the resistant strain, compared to over 90% in the susceptible insects. Despite a 52-fold ovicidal resistance ratio to the juvenile hormone analog fenoxycarb, this compound induced a 85% decrease in hatching in the resistant strain. Conversely the newly hatched larvae of the resistant strain exhibited a 45 000-, 33- and 2.1-fold resistance ratio to diflubenzuron, teflubenzuron and flufenoxuron, respectively. The latter value was not significant, and the field rate of flufenoxuron killed over 97% of the resistant larvae while diflubenzuron had no effect. This lack of relationship between ovicidal and larvicidal resistance may be due to different transport properties together with differential enzymatic metabolization. Our results may limit the validity of substitution instars, which approach is frequently used for resistance monitoring. More importantly for resistance management, the resistance of different target instars to each compound has to be considered when establishing control strategies.     

Haemolymph protein reserves of diapausing and nondiapausing codling moth larvae, Cydia pomonella (L) (Lepidoptera: Tortricidae)

Haemolymph from diapausing codling moth larvae contain a dominant soluble protein, which is of minor significance in the haemolymph of nondiapausing larvae. This haemolymph protein is accumulated during the ultimate larval instar and its concentration is maintained throughout diapause development. Larvae induced into a diapause-like condition following topical treatment with a juvenile hormone mimie stored the haemolymph protein.     

Identification of further sex pheromone synergists in the codling moth, Cydia pomonella

A number of angiosperm nonhost volatiles (NHVs) and green leaf volatiles (GLVs) were tested alone and as supplements to the antiaggregation pheromone, verbenone, for their ability to disrupt attack by the mountain pine beetle (MPB), Dendroctonus ponderosae Hopkins (Coleoptera: Scolytidae), on lodgepole pine, Pinus contorta Dougl. ex Loud. var. latifolia Engel. Preliminary experiments led to a refined NHV blend [benzyl alcohol, guaiacol, benzaldehyde, nonanal, salicylaldehyde, and conophthorin] and a refined GLV blend [(Z)-3-hexen-1-ol and (E)-2-hexen-1-ol]. In a 20-replicate experiment, NHV and GLV groups both singly, and verbenone alone, significantly reduced MPB mass attack on pheromone-baited trees and on trees within 5 m of the pheromone-baited trees. Both blends in combination with verbenone reduced the number of mass attacked, baited trees to three out of 20 compared to 20 out of 20 of the baited controls. Each binary combination was also effective at reducing mass attack. In these experiments, all tested repellents were released from devices stapled to trees at the same point as the pheromone bait, suggesting that the repellency could have been to a point source, rather than to the whole tree. Therefore, in two further experiments bands of release devices were wrapped around the treated trees and the pheromone bait was removed from the treated trees. In one experiment, when the aggregation pheromone bait was suspended between pairs of trees treated with the NHV blend plus GLV blend plus verbenone, only three out of 25 treated pairs had mass attack on at least one member of the pair. In the other 60-replicate experiment, with no pheromone baits present, attack occurred on 13 untreated and 11 banded trees, all in the path of a large advancing infestation. However, the mean attack density on the banded trees was significantly reduced to a level below the 40 attacks m^–2 of bark surface required to kill a healthy lodgepole pine. As a result of these experiments, operational trials are recommended.     

Overwintering of codling moth (Lepidoptera: Tortricidae) larvae in apple harvest bins and subsequent moth emergence.

Codling moths, Cydia pomonella (L.), have long been suspected of emerging from stacks of harvest bins in the spring and causing damage to nearby apple and pear orchards. With increased use of mating disruption for codling moth control, outside sources of infestation have become more of a concern for growers using pheromone based mating disruption systems. Studies were designed to provide information on bins as a source of codling moth and the pattern of codling moth emergence from stacks of bins. In these studies, codling moth larvae colonized wood harvest bins at a much higher frequency than harvest bins made of injection molded plastic (189 moths emerged from wood compared with five from plastic). There was no statistical difference in the number of moths infesting bins that had been filled with infested fruit compared with bins left empty at harvest. This suggests that codling moth enter the bins during the time that the bins are in the orchard before harvest. Emergence of laboratory reared adult codling moth from wood bins placed in stacks was found to be prolonged compared with field populations. Temperature differences within the bin stacks accounted for this attenuated emergence pattern. Covering bin stacks with clear plastic accelerated codling moth development in the upper levels of the stack. Codling moth emergence patterns from plastic-covered stacks more closely coincided with male flight in field populations. This information could be important in developing a technique for neutralizing codling moth-infested bins, and in understanding how infested bins may influence pest management in fruit orchards that are located near bin piles. Implications for control of codling moth in conventional orchards and in those using mating disruption as the principal component of an integrated pest management system include increased numbers of treatments directed at areas affected by infested bins.     

Survival of mature larvae of codling moth (Cydia pomonella) on apple trees and ground

The effects of predation by carabid and staphylinid beetles and birds (blue- and great-tits) on mature larvae of the codling moth Cydia pomonella were investigated in a field experiment. The number of predatory beetles on the ground beneath eight of 16 apple trees was reduced by an insecticide spray, and tits were excluded from the trunks and lower branches of eight trees by means of Terylene netting. Beetles had no significant effect on survival of larvae on trees, but only 8% of larvae survived to adulthood on trees exposed to blue- and great-tits, whereas on trees protected from them 48% survived. Larvae were taken rapidly by the tits from the time larvae first built cocoons in summer and, by the time the majority of larvae had emerged from apples in late summer or autumn, tits had removed most from cocoons beneath flakes of bark glued to trees. Thus tits fed on larvae mainly in summer and autumn. On trees protected from tits, 8% of mature larvae were killed by fungi, of which Verticillium lecanii was most important. It was calculated that, of the larvae maturing in apples, 44% failed to build cocoons on the trees, 47% were taken by tits, then 1% were killed by fungi. Larvae failing to build cocoons on trees may build them on the ground. Of larvae in cocoons planted on or in the ground in 1975, only one (0.3%) persisted through the winter; 98.6% disappeared, and 1.1% were found dead, covered by fungi; in 1976, all larvae disappeared by December. Larvae disappeared even in the absence of predators, and are thought to have moved in response to damp ground conditions.     

Effect of monosodium glutamate on apple leaf consumption by codling moth larvae

We have demonstrated that larvae of codling moth, Cydia pomonella (L) can successfully complete their first instar when fed apple leaves instead of fruit. Larvae fed leaves after hatching maximized their feeding intensity (about 320 g/larva/day) on day 2. Weight gain revealed a stereotypic sigmoid pattern that peaked on day 3. Although the maximum body weight of larvae fed leaves was 70–85% less than for larvae maintained on apples or on artificial diet, 100% of larvae fed leaves molted to the second instar 3–5 days after hatching. Our investigation revealed a diurnal pattern of leaf ingestion, and neonates' feeding intensity decreased significantly during the scotophase. We also demonstrated that monosodium glutamate (MSG) increased feeding on leaves by codling moth larvae. Depending on the duration of the bioassay, and larval age at time of initial exposure, 0.05 mg/ml and 0.1 mg/ml MSG increased apple leaf consumption by 25–60% over leaves alone. The effect of monosodium glutamate was best demonstrated during the first day following hatching. Exposure to MSG also accelerated molting to the second instar. Larvae exposed to MSG initiated consumption of leaf tissue significantly earlier than control neonates. The feeding stimulatory effect of MSG was not observed if exposure to this chemical was delayed until 3–4 h after hatch.The addition of feeding stimulants to pesticides that act via the alimentary tract may reduce the amount of active ingredients needed to maintain the efficacy of these formulations. Here, we postulate that first instar codling moth larvae are potential targets for treatment with pesticide formulations enhanced with monosodium glutamate.     

Attraction of codling moth males to apple volatiles

The attraction of the codling moth, Cydia pomonella, to apple volatile compounds known to elicit an antennal response was tested both in the field and in a wind tunnel. In the field, (E)‐β‐farnesene captured male moths. The addition of other apple volatiles, including (E,E)‐α‐farnesene, linalool, or (E,E)‐farnesol to (E)‐β‐farnesene did not significantly augment trap catch. Few females were caught in traps which also caught male moths, but female captures were not significantly different from blank traps. In the wind tunnel, males were attracted to (E,E)‐farnesol, but not to (E)‐β‐farnesene. The addition of (E,E)‐α‐farnesene to (E)‐β‐farnesene had a synergistic effect on male attraction. The male behavioural sequence elicited by plant volatiles, including upwind flight behaviour, was indistinguishable from the behaviour elicited by sex pheromone.     

Attachment ability of the codling moth Cydia pomonella L. to rough substrates

Host plant surfaces of the codling moth, Cydia pomonella L. (Lepidoptera, Tortricidae), vary in microtopography, which can affect its attachment, locomotion, and oviposition behaviour. This study was performed to investigate the effect of surface roughness on the attachment ability of adult insects. Using a centrifugal force device, friction forces of both sexes were assessed on six epoxy resin substrates differing only in the dimensions of their surface asperities, ranging from 0 μm to 12 μm. Surface topography significantly affected friction forces. Maximal force was measured on the smooth substrate whereas minimal force was assessed on microrough substrates with 0.3 μm and 1.0 μm size of asperities. On the remaining rough substrates, friction forces were significantly higher but still lower than on the smooth substrate. Both sexes generated similar forces on the same substrate, in spite of the considerable difference in their body mass. Thus, it is expected that both sexes can attach effectively to differently structured plant substrates in their habitat. However, since smooth surfaces have been reported previously to be the most favorable substrates for ovipositing females of C. pomonella, it is possible that they use their attachment system to sense the substrate texture and prefer those substrates to which their arolia attach the best.     

苹果蠹蛾气味结合蛋白基因CpomOBP20的克隆及表达分析

[目的] 通过克隆苹果蠹蛾气味结合蛋白CpomOBP20基因cDNA序列,分析其序列特征和表达谱,旨在更好地了解OBP基因在苹果蠹蛾生命活动过程中的作用,为该害虫的绿色防控提供理论支撑。[方法] 采用RT-PCR法扩增苹果蠹蛾气味结合蛋白CpomOBP20基因cDNA序列,并使用生物信息学软件对其核苷酸和氨基酸序列进行分析;基于qPCR技术分析CpomOBP20基因在苹果蠹蛾4龄幼虫不同组织(头、血淋巴、表皮、脂肪体、中肠、马氏管和唾液腺)以及雌雄成虫不同末端组织(头、触角、下唇须、喙、足和翅)中的表达情况,利用分子对接研究了CpomOBP20与3种保幼激素的结合能力。[结果] 苹果蠹蛾气味结合蛋白CpomOBP20基因的开放阅读框长459 bp,共编码152个氨基酸,等电点为6.30,蛋白分子质量为16.264 ku,N末端具有20个氨基酸组成的信号肽序列,蛋白质序列中具有6个保守的半胱氨酸残基,属于Classical OBP。序列分析表明,CpomOBP20的氨基酸序列与小菜蛾OBP (XP_011557123.1)的一致性最高,在亲缘关系上更加接近。qPCR结果表明,CpomOBP20基因在苹果蠹蛾4龄幼虫以及雌雄成虫不同组织中均有表达,其中在4龄幼虫的血淋巴中表达量最高,在雌雄成虫表达量最高的分别是翅和足,其次是头部。分子对接结果表明,CpomOBP20与3种保幼激素均具有较好的结合能力,可能参与保幼激素的结合与转运。[结论] 本研究明确了CpomOBP20的核苷酸和氨基酸序列的组成及编码蛋白的理化性质,并推测CpomOBP20的作用可能不仅局限于嗅觉识别,在非嗅觉器官中也可能起着重要的生理作用,为今后更深入地探究气味结合蛋白在苹果蠹蛾生命活动中的作用机理提供数据支撑。     

The hormonal regulation of the larval diapause in the codling moth, Laspeyresia pomonella (Lep. Tortricidae)

The hormonal control of the facultative diapause of the codling moth has been investigated. The diapause can be divided into 4 phases or periods: (1) diapause induction by short-day conditions (SD) in young larvae, (2) initiation of the diapause in the early last larval instar by a high titre of juvenile hormone, (3) onset and maintenance of diapause with inactivity of the neuroendocrine system, as evidenced by the results of neck-ligation experiments, (4)termination of diapause by the production of ecdysteroid.Diapause-induced larvae pupated after spinning the cocoon, if the state of induction was changed by injection with the anti-juvenile hormone precocene II at the beginning of the last larval instar and subsequent results of neck-ligation experiments, (4) termination of diapause by the production of ecdysteroid. treated with juvenile hormone during the first 1.5 days after the last larval moult and subsequently reared under SD. Under LD, continuous application of juvenile hormone during the last larval instar and after spinning did not prevent the insects from moulting to either a supernumerary larva, a pupa or a larval-pupal intermediate. Termination of diapause, i.e. pupation, was achieved by injecting diapausing larvae with 20-hydroxyecdysone. Although juvenile hormone was found to have a prothoractropic effect in diapausing larvae, no pupal moult could be induced by the application of the hormone. Contrary to the hormonal situation before pupation of nondiapausing larvae, no juvenile hormone could be detected before or during the pupation of larvae after diapause.     

Possible mechanisms of the difference in sensitivity of caterpillars of Adoxophyes orana and Laspeyresia pomonella to diflubenzuron

The sensitivity to diflubenzuron varies considerably among species of caterpillars that cause damage to fruit. The cause of this difference in sensitivity was studied in larvae of Adoxophyes orana F. R., a not so sensitive species and Laspeyresia pomonella L., a species that is highly sensitive. Results indicate that the ingestion pattern of diflubenzuron and significance of chitin synthesis to these species are of importance for explaining the difference. It is uncertain whether there is a difference in the affinity of the sites of action of A. orana and L. pomonella for diflubenzuron.

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Résumé La sensibilité au diflubenzuron varie considérablement suivant les espèces de lépidoptères qui provoquent des dégâts aux fruits. La cause de ces différences de sensibilité a été étudiée chez les larves d'Adoxophyes orana, une espèce peu sensible, et de Laspeyresia pomonella qui est très sensible. Les résultats soulignent l'importance du processus d'ingestion du diflubenzuron et de la synthèse de la chitine pour expliquer cette différence. Il n'est pas sûr qu'il y ait une différence d'affinité au diflubenzuron des cibles de A. orana et L. pomonella.

     

Disruption of sexual communication in Laspeyresia pomonella1 (codling moth), Grapholitha molesta1 (Oriental fruit moth) and G. Prunivora1 (lesser appleworm) with hollow fiber attractant sources

Emission of (Z)-8-dodecenyl acetate [7% (E) isomer] from hollow fiber dispensers at 0.15 g/ha/day from 1700 points (units of 10 fibers)/ha effects complete disruption of male Grapholitha molesta (Busck) attraction to synthetic lure and virgin females. Attraction of G. prunivora (Walsh) to synthetic lures is also completely disrupted. Emission of (E,E)-8,10-dodecadien-1-ol at 0.05 g/ha/day from 1700 points/ha effects complete disruption of male Laspeyresia pomonella (L.) attraction to synthetic pheromone, to virgin females and prevents mating with tethered females.

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Résumé L'émission du composé (Z)-8-dodecenyl acetate (7% de l'isomère E 8-12 Ac dans le texte), à la dose de 0,15 g/ha/jour, à partir d'émetteurs formés d'une fibre creuse (type Conrel (R)), répartis en 1700 points/ha, chaque point comportant des unités de 10 fibres, annihile complètement l'attraction du mâle de Grapholitha molesta à l'égard de femelles vierges ou de leures chimiques de synthèse. L'attraction de G. prunivora pour des leures synthétiques est également totalement interrompue.L'émission du composé E8 E10-dodécadien-1-ol (E8 E10-12:OH) à la dose de 0,05 g/ha/jour, à partir de 1700 points/ha, entraîne la destruction totale du comportement attractif de Laspeyresia pomonella pour des hormones de synthèse, ou pour des femelles vierges et empêche l'accouplement avec des femelles non mobiles liées par un système adhésif à un dispositif attractif (pherotrap 1C).

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Lepidoptera: Tortricidae: Olethreutinae     

Environmental regulation of female calling and male pheromone response periodicities in the codling moth (Laspeyresia pomonella)

Codling moth female calling and male pheromone responsiveness under the defined conditions of 23°C and light:dark (LD) 16:8 occurred primarily during scotophase. Under either continuous photophase or scotophase females called with periodicities very similar to their periodicity under the LD cycle, indicating that the rhythmicity is circadian. Male response rhythmicity was maintained under continuous photophase. A decrease in the temperature from 23° to 16°C resulted in a reduction in the proportion calling when the decrease in temperature occurred during scotophase and a shift of maximal calling into photophase when the decrease in temperature occurred 3 hr prior to the initiation of scotophase. Decreases of temperature from 23° to 16°C and of light intensity did not produce similar shifts in the periodicity of male upwind orientation. Of 6 pheromone dosages from 10^?5 to 10² μg, 10^?1 and 10⁰ μg elicited the most male upwind orientation.     

Control of diapause in codling moth larvae

Diapause in a New Zealand strain of codling moth (Cydia pomonella Linnaeus [Lepidoptera: Olethreutidae]) was induced in larvae by photoperiods of 15 h or less. Once diapause had been initiated, it could not be terminated by any combination of conditions tested for at least 20 days after cocooning. In diapausing larvae a low rate of pupation occurred at 25 °C under a long day (18 h) photoperiod. A high rate of pupation was achieved under a long day regime when larvae were decocooned, and provided with apple as nourishment. Diapause could be terminated predictably in 94–100% of larvae by 1) conditioning at 15 °C and constant darkness for periods of 40–100 days, then 2) chilling at 2±2 °C and constant darkness for 20–50 days followed by 3) any post-chill condition periods at 25 °C, 18 h photoperiod. Complete diapause termination was achieved when 100 days conditioning was followed by 30 days or 50 days post-chill period. Under these conditions, 76% termination occurred in the post-chill period after 10 days, and 93% after 25 days.To terminate diapause in codling moth larvae, we recommend that a 100 days conditioning followed by 30 days chilling and 50 days post chilling periods be used.