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Simple Summary: Ants are widespread across terrestrial ecosystems, including agroecosystems, where they take part in several important processes. They often can act as predators of a wide range of insect pests in agricultural fields, which should be considered by management programs, and can sometimes be actively exploited to promote sustainable biological control strategies. In a recent experiment conducted in Europe, pear trees visited by larger numbers of ants suffered fewer attacks to their fruits by the codling moth, a small lepidopteran, which is a significant economic pest worldwide, especially in apple, pear, and walnut orchards. However, the exact form of the interaction between the ants and codling moths remained unclear. While ants were already known to prey upon mature larvae or pupae in the soil, this new evidence suggested they could also control the eggs or newly hatched larvae that had not yet attacked the fruits, which are the two stages whose removal would directly prevent fruit damage. We conducted laboratory experiments to determine whether two common European ants could prey upon these stages. Our results suggest that these ants are effectively able to kill newly hatched larvae, while the eggs do not appear directly vulnerable to predation. Further investigation under field conditions would be needed to assess whether ants may also interfere with the oviposition by adult moths. The predatory ability of ants (Hymenoptera, Formicidae) against insect pests can offer an important service to agricultural activities and may sometimes be directly exploited in biological control strategies. The codling moth Cydia pomonella (Lepidoptera, Tortricidae) is a major agricultural pest of fruit orchards, whose biological control is complicated by the fact that the larvae spend most of their life protected within the fruits they damage. In a recent experiment in Europe, pear trees in which ant activity was artificially increased by the addition of sugary liquid dispensers (artificial nectaries) suffered less damage caused by the larvae to their fruits. While some ants were already known to prey upon the mature larvae or pupae of C. pomonella in the soil, prevention of fruit damage would require predation upon eggs or newly hatched larvae, which have not yet excavated into the fruits. We verified whether two different Mediterranean ants frequently observed in fruit orchards, Crematogaster scutellaris and Tapinoma magnum, were able to prey upon C. pomonella eggs and larvae in laboratory conditions. Our experiments demonstrated that both species similarly attacked and killed young C. pomonella larvae. On the other hand, the eggs mostly attracted the attention of T. magnum but were never damaged. Further field assessments are required to understand whether ants may also interfere with oviposition by adults or whether larger ant species, although generally rarer in orchards, may also prey upon eggs. [ABSTRACT FROM AUTHOR]

The more restrictive regulations of pesticides in Europe have led to an increase in conservation biological control (CBC) research. However, little attention has been paid to the main determinants of Lobesia botrana parasitism. The Douro Demarcated Region landscape offers scope for the use of CBC. The study was conducted between 2002 and 2015 aiming at: (i) identifying parasitoids associated with L. botrana and evaluating their impact as biological control agents in each generation of the pest, and (ii) evaluating the effect of both the proportion of ecological infrastructures (EI) near the vineyards, and the impact of management practices (chemical treatments and ground cover) on the parasitism of L. botrana. A total of 3226 larvae/pupae of L. botrana were collected (15% were parasitized and 485 parasitoids emerged). A complex of 16 taxa of parasitoids was identified, the majority belonging to Hymenoptera. The most abundant were Elachertus sp. (Eulophidae), Campoplex capitator Aubert (Ichneumonidae), and Brachymeria tibialis (Walker) (Chalcididae), which represented 62.5, 12.6, and 12.0% of the total assemblage of parasitoids which emerged, respectively. The percentage of parasitism ranged from 0.0 to 61.5% (first generation), from 0.0 to 36.8% (second generation), and from 0.0 to 12.1% (third generation). Importantly, it was found that the parasitism rate was higher in vineyards with ground cover. In addition, EI in the area surrounding the vineyards produced a significant increase in parasitism. These results suggest potential for CBC of L. botrana if EI around vineyards, and ground cover with native perennial plants within vineyards, are encouraged. [ABSTRACT FROM AUTHOR]

The European grape berry moth, Eupoecilia ambiguella (Hübner) (Lepidoptera: Tortricidae), since its first identification in 1796, was defined as a key pest for European viticulture despite its polyphagy. Although between the late 1800s and early 1900s its presence and spread in Europe was of concern, to date its populations are low and limited to cooler and wetter areas, leading to a decline in its importance. In the present work, we reviewed its global distribution as well as its morphology, biology, and ecology. Considering the monitoring and management of this pest, the present review summarised insecticidal, agronomic, and cultural control strategies. Moreover, given the need to reduce the impact of agriculture on the environment, humans, and non-target species, we focused on control strategies relying on pheromones and biological control agents (e.g. predators and parasitoids) involved in conservation biological control. • The European grape berry moth, Eupoecilia ambiguella , has a long history as grape pest. • We reviewed knowledge on its morphology, bio-ecology, and geographical distribution. • Current monitoring and management tools were discussed. • Potential biocontrol agents were extensively reviewed. • Challenges for E. ambiguella IPM and biological control were formulated. [ABSTRACT FROM AUTHOR]

Notes on the presence of the Omnivorous Leafroller, Platynota stultana (Lepidoptera Tortricidae), in Italy and its presence and interception in other European countries are reported. Geographical distributions and principal morphological and biological characters are illustrated. Considering the wide host range of P. stultana, this pest has the potential to damage many cultivated and wild plants in the European and Mediterranean Plant Protection Organization (EPPO) region. Its interception in England, the Netherlands, and Germany and its introduction into Spain and Italy clearly demonstrates that it has the potential to enter and establish itself in the Southern and Mediterranean parts of Europe. [ABSTRACT FROM AUTHOR]

The European grapevine moth (Lobesia botrana) is currently the most damaging pest in many viticultural regions of South and Central Europe and is highly responsible for the development of secondary infections by Botrytis cinerea to both table and wine grapes. Entomopathogenic fungi (EPF) are considered as substantial biological control agents of insect pests. However, they are able to infect their hosts only under a narrow spectrum of environmental conditions. In this study, the effects of temperature on pathogenicity of EPF for the control of L. botrana are reported. Among a collection of 33 EPF isolates, six virulent isolates were selected for the experiments. The bioassays took place at controlled conditions, under the temperature regimes of 20, 22.5, 25, 27.5, 30, and 32.5 °C. A conidial concentration of 1 × 108 conidia/ml was prepared for each isolate, and fungi were applied by spraying them on third-instar larvae (L3) of L. botrana. Both factors, fungal isolate and temperature, significantly affected mortality of L. botrana. Most fungal isolates exhibited their highest larval mortality rates seven days post-treatment at the temperatures of 25 and 27.5 °C. Some isolates caused considerably high larval mortality that exceeded 90% under specific temperature conditions. Overall, EPF showed great potential as bio-control agents for controlling larval populations of L. botrana. [Display omitted] • Entomogenous fungi showed great potential as biocontrol agents of Lobesia botrana. • Temperature significantly influenced all fungi on larval mortality of L. botrana. • An isolate from a cool region (Isaria fumosorosea EBAC01) was the most virulent. • Most fungal isolates demonstrated their highest efficacy at 25 and 27.5 °C. [ABSTRACT FROM AUTHOR]

Passive dispensers are the most widely used dispensers to control the European grapevine moth, Lobesia botrana (Denis & Schiffermüller) (Lepidoptera: Tortricidae), by mating disruption (MD). Although their efficacy is well-proven, efforts are needed to reduce the use of pheromone without compromising efficacy and to allow lower MD costs. For this purpose, two different widely employed dispenser types in Europe against this pest (Ampoule and Rope dispensers) were evaluated in the field to verify their performance (emission rates and efficacy) in relation to weather conditions. Their release profiles were studied by extracting and quantifying the residual pheromone load over time by gas chromatography. Dispensers' performance in relation to weather conditions was then assessed by correlating the daily emission rates with the mean daily values of several of these variables. Although both dispenser types were efficient in controlling L. botrana populations and reducing fruit damage, their pheromone content and their release rates differed at the end of the crop cycle. The Ampoule dispensers emitted lower amounts of pheromone throughout the study period, whereas the Rope dispensers' emissions were weather-dependent, with higher emission rates at higher mean temperatures and wind speeds. Our results showed that the current commercial MD dispensers could be improved by adjusting their release rates to better reflect actual pheromone requirements. [Display omitted] • Both passive dispensers performed efficiently controlling L. botrana populations and reducing fruit damage. • Ampoule dispensers keep the efficacy with lower emission rates and can be more suitable for late cultivars. • Rope dispensers' emission was higher at higher mean temperatures and wind speeds. • Commercial mating disruption dispensers can be improved by reducing pheromone waste. [ABSTRACT FROM AUTHOR]

Thirty-five codling moth ( CM, Cydia pomonella L., Lepidoptera, Tortricidae) populations collected in different commercial orchards in six European countries were tested for their susceptibility to Cydia pomonella granulovirus ( Cp GV- M). Including previously published data on Cp GV- M resistance, a total of 38 CM colonies showed considerably elevated LC50 values, independent of the country origin. When only few test individuals are available, determination of mortality of neonate larvae at a discriminating concentration range of 104 to 106 OB/ml (>log4) as a direct measure of percentage susceptible individuals in a CM population is more advisable than calculation of LC50 values. The >log4 mortality alone or in combination with the LC50 value can be used for identification of resistance in a population. Results indicated a locally separated but widely spread occurrence of CM populations with low susceptibility to Cp GV- M. The most plausible hypothesis for the emergence of Cp GV- M resistance is its selection by repeated use of Cp GV products. [ABSTRACT FROM AUTHOR]

Although the Chestnut Leaf-roller Pammene fasciana is always included among the main chestnut-feeding tortrix moths in Europe (together with Cydia splendana and C. fagiglandana), its actual distribution has never been investigated in detail, since it is often considered to be a minor pest. A survey of Tortricidae feeding on chestnuts in Greece revealed not only that P. fasciana is present, but also that in some regions the leaf-roller's distribution is directly comparable to that of the other two Cydia species. This is the first time that the exact geographic distribution of P. fasciana within a country has been determined, and suggests that this leaf-roller's significance as a pest has been seriously underestimated. In order to facilitate the identification of this pest in future studies, the DNA barcode of P. fasciana has been elucidated and deposited in a data bank. [ABSTRACT FROM PUBLISHER]

The moth Lobesia botrana (Denis & Schiffermtiller) (Lepidoptera: Tortricidae) feeds on grapes (Vitis vinifera L.), reducing yield and increasing susceptibility to fungal infections. L. botrana is among the most economically important insects in Europe and has recently been found in vineyards in Chile, Argentina, and California. Here, we review L. botrana biology and behavior in relation to its larval host (the grapevine) and its natural enemies. We also discuss current and future control strategies in light of our knowledge of chemical ecology, with an emphasis on the use of the sex pheromone-based strategies as an environmentally safe management approach. Pheromone-mediated mating disruption is the most promising technique available on grapes and is currently implemented on ≈140,000 ha in Europe. Experience from several growing areas confirms the importance of collaboration between research, extension, growers, and pheromone-supply companies for the successful implementation of the mating disruption technique. In the vineyards where mating disruption has been successfully applied as an areawide strategy, the reduction in insecticide use has improved the quality of life for growers, consumers, as well as the public living near wine-growing areas and has thereby reduced the conflict between agricultural and urban communities. [ABSTRACT FROM AUTHOR]

The fruit pests Cydia pomonella (L.), Crapholita molesta (Busck), Grapholitafunebrana Treitschke, and Grapholita lobarzewskii Nowicki (all Lepidoptera: Tortricidae) are sympatric in Europe, and some of them are expanding their distribution range worldwide by continuous invasion into new areas. Identification of the small larvae by morphological characters and damage symptoms is difficult, and many misidentifications among these tortricids of the tribe Grapholitini are reported. In the current study, the species were separated using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analyses. Samples were obtained from different countries and continents, and the mitochondrial cytochrome oxidase subunit I (COl) fragments of one individual per species and geographical site were sequenced. Based on the alignments of the amplified COl sequences, the PCR-RFLP method was established with 42 individuals and successfully validated using a total of 122 individuals of the four species. Results document that this method allows for discrimination of larvae, pupae, and adult specimens of all four species and can be used for a rapid and reliable identification of C. pomonella, C. molesta, C. funebrana, and G. lobarzewskii. Moreover, it can easily be expanded to other internal tortricid fruit feeder species that occur on different continents. [ABSTRACT FROM AUTHOR]

Adult braconid wasps ( Bracon sp.) emerged from the droppings of frugivorous birds ( Turdus blackbirds and thrushes) collected in a rural environment in southern Europe. It was thus demonstrated for the first time that an insect parasitoid of a fruit-infesting insect (lepidopteran tortricid) can survive bird ingestion and gut passage inside a seed (privet Ligustrum vulgare), constituting a case of an evolutionary tetrad. [ABSTRACT FROM AUTHOR]

The European grapevine moth, Lobesia botrana (Denis & Schiffermüller) (Lepidoptera: Tortricidae), is a major grapevine pest in Europe. The larva is polyphagous and able to develop on more than 25 plant species, several of them being more suitable than Vitaceae for the fitness of L. botrana. Larvae normally eat the pulp of the berry, but may also consume the seeds according to the development stage of the berry and the larval density per bunch. Understanding the effect on individual fitness of such feeding behaviour is important to assess how suitable the different berry tissues are for this insect. We offered to the larvae either entire berries, seeds, or pulp with skin of the variety Vitis vinifera cv. ‘Cabernet Sauvignon’ as larval food in order to assess several life history traits from egg hatching to adult death. Two control groups were raised on semisynthetic diets, offering a low (no plant material) or a higher (with corn flour) nutritive value medium. The larvae performed differently when fed on diets containing different parts of berries. The larvae fed on a diet containing grape berry seeds had a prolonged development time and showed higher mortality. The females emerging from these larvae had a lower fecundity and mating success than the females emerging from larvae fed on diets containing other parts of the berries. However, their longevity was greater in comparison to the other groups. We conclude that seeds of Cabernet Sauvignon are not toxic to larvae but affect the reproductive life history traits in L. botrana. [ABSTRACT FROM AUTHOR]

The large fruit-tree tortrix Archips podana (Scopoli) is a widely distributed species in the whole of Europe. The species is variable in male genitalia. According to the different number and position of apical (A) and lateral (L) spikes on the aedeagus, .A, L, 2L, AL, A2L, and 0 (without spike) phenotypes were discriminated. To determine the variability of pheromone communication of A. podana, field trap tests were conducted in different habitats and geographical regions in Estonia (Uhti and Otepää), northwestern Russia (Velikie Luki, Pskov Region), and the North Caucasus (Krasnodar Territory). The optimum content of Z-11-tetradecenyl acetate in pheromone blend, calculated using the Gaussian curve, was on average 61.3 ± 1.3%. This is practically identical to the ratio of 60:40 in the mixture of (Z)- and (E)-11-tetradecen-1-yl acetates identified by Persoons et al. (1994, J. Insect Physiol., 20, 1181–1188). Experiments demonstrated that the optimal pheromone composition was the same in Krasnodar, where the L phenotype dominates, and in Velikie Luki and Estonia, where A phenotype males dominate. A deviation of attractive blend from optimum ratio causes a comparable decrease in trap catches for males of different aedeagus forms. The Caucasian subspecies with a lateral spike (male phenotype L), A. podana meridiana Kozl. et Esart., is placed in synonymy to nominotypical species in this paper. Calculation of pheromone communication parameters - channel width and optimal ratio - is an effective tool for ecochemical research and dispenser modelling. [ABSTRACT FROM AUTHOR]

C. florus is a multivoltine, gregarious, non-paralyzing ectoparasitoid of various tortricid species (Lep., Tortricidae), mostly found in cultured area's in Europe. In The Netherlands high percentages of parasitism by C. florus of A. orana were often observed in the summer. Host finding, parasitization behaviour, clutch size and sex ratio regulation of progeny was studied. C. florus was evidently attracted by odours originating from the specific host habitat with host retreates containing hosts. Contact chemicals from host retreats evoked always an arrestment response followed by area-restricted search. The giving-up time was related to the probability to find a host. Inexperienced virgin or inseminated females adjusted their clutch size to host size in order to obtain similar sized and optimal functional individuals emerging the brood of a single host. Inseminated females were even able to adjust the sex ratio of a brood to maximize the number of inseminated daughters. Feeding larval hosts (L3, L4, L5) were parasitized right away. Larval-larval pro-ecdysis hosts were temporary unsuitable, but were not rejected, host ecdysis was awaited and followed by parasitization. Clutch size and sex ratio regulation are discussed in connection with a single host resource and a patch of hosts searched. Zusammenfassung Parasitierungs-Strategie bei dem nicht-paralysierenden Ektoparasitoiden Colpoclypeus florus (Hym., Eulophidae) gegenüber seinem gewöhnlichen Sommerwirt Adoxophyes orana (Lep., Tortricidae). 1. Wirts-Findung, -Annahme und -Ausnutzung Colpoclypeus florus ist ein multivoltiner, gregär lebender Ektoparasit mehrerer Tortriciden (Lep., Tortricidae), der seine Wirte nicht paralysiert. Er ist allgemein verbreitet in den Kulturlandschaften Europas. In den Niederlanden wird oft im Sommer hohe Parasitierung von Adoxophyes orana durch C. florus gefunden. Das Auffinden des Wirtes, Parasitierungsverhalten, Brutgröße und die Beeinflussung der Geschlechterverhältnisse der Nachkommen wurden untersucht. C. florus wurde eindeutig von Duftstoffen angelockt, die von Wirtsgespinsten mit den darin enthaltenen Wirtslarven ausgehen. Chemische Berührungsreize führten immer zum Stehenbleiben des Parasitenweibchens, gefolgt von einer Suchphase in begrenztem Raum. Die Dauer stand in Beziehung zu der Wahrscheinlichkeit, einen Wirt zu finden. Sowohl unerfahrene, unbegattete als auch begattete Weibchen regulierten die Zahl ihrer Nachkommen je nach der Größe der Wirtslarve, wodurch in jeder Brut die Entwicklung normaler, voll funktionsfähiger Nachkommen sichergestellt wird. Begattete Weibchen zeigten die Fähigkeit, das Geschlechterverhältnis der Nachkommenschaft in einer Brut zu beeinflussen und den Anteil an Töchtern zu maximieren, die in der Regel noch im Wirtsgespinst von ihren Brüdern begattet wurden. Aktive Larven der Stadien 3-5 wurden sofort parasitiert, nicht solche kurz vor der Häutung. Sie wurden nicht zurückgewiesen, aber die Parasitierung folgte erst nach der Häutung. Brutgröße und die Regulierung des Geschlechterverhältnisses bei der Suche nach einzelnen oder Gruppen von Wirten werden diskutiert. [ABSTRACT FROM AUTHOR]

Six microsatellite markers were developed for the larch budmoth Zeiraphera diniana Guénée 1845, using two enrichment protocols. The number of alleles ranged from 3 to 15 per locus and observed heterozygosities ranged from 0.09 to 0.98 for the 69 individuals genotyped. Using these markers significant genetic differentiation between one population from Poland and samples from Alpine populations in France and Switzerland (overall FST = 0.0298) was detected. However, the two Alpine samples did not differ significantly. These microsatellite markers are valuable tools for studying the population genetics of Zeiraphera diniana. [ABSTRACT FROM AUTHOR]