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Drosophila suzukii, spotted wing drosophila, is recognized as an economically significant new invasive pest of stone and, especially, berry fruits. This pest has been registered on the EPPO-A2 quarantine list. Due to the limited presence of natural predators on the European continent, this pest quickly proliferates, posing a significant threat to the agricultural economy by causing substantial losses in fruit production. As D. suzukii infestations commonly occur during the ripening stage, the main obstacle with chemical control methods is the risk of high residue in fruits. To face this issue, it is crucial to explore alternative control strategies. One of the possible effective methods involves the use of plant-derived bioactive compounds. Currently, there is ongoing research to identify essential oils with potential insecticidal properties for combating this challenge. The objective of this study was to assess the insecticidal and behavioural impacts of anise (Pimpinella anisum L.) essential oils on D. suzukii adults in a multiple-choice test using blueberries treated with three concentrations of the anise essential oil. Additionally, the study monitored the emergence of adults from the treated berries. Using GC-MC chromatography, Bošković et al. the chemical composition of anise essential oil was determined, in order to understand the possible mode of action. The essential oil of anise showed high efficacy in the multiple choice test, since a lower number of laid eggs was recorded at all three application concentrations (1%, 5% and 10%) compared to the control (water and acetone). Our findings suggest that anise essential oil can serve as an alternative to chemical insecticides, which would enable the use of bioinsecticides based on this oil, in conventional, integrated, and organic crop production.

Simple Summary: Exploring insects' biology through growth chamber experiments is a common practice that provides quantitative information on the stage-response of the species to external factors. Those experiments are commonly indicated as "Life tables studies" and provide for rearing a cohort of eggs under different conditions of temperature, relative humidity, diet, and photoperiod, to cite some examples. Tracking the life history of the individuals, it is possible to assess how the growth conditions affect the stage-development time, the stage-mortality, and the reproduction rate (egg production, pre-oviposition period, and coupling). Besides the biological knowledge, the quantitative information resulting from life table studies allows the parameter estimation of physiologically-based models. For this reason, life table studies are widely applied to insect pests, and they represent a piece of fundamental knowledge that can potentially drive integrated management programmes. This study explored the thermal response of Drosophila suzukii, an injurious insect pest present in many countries worldwide, at different controlled conditions. This species is responsible for several economic losses in soft fruit cultivations, develops on ripening fruits, and has the capability to quickly adapt to new territories and climates, closing multiple generations per year. Given its high invasive potential and the increasing need for low-impact control strategies, an in-depth exploration of the biology of this species and of the stage thermal response is fundamental. Specimens of an Italian strain from Apulia were reared in growth chambers at different constant temperatures (6, 9, 13, 18, 20, 24, 25, 26, 27, 28, 29, 31, 32 and 33 °C). The life cycle of each specimen was individually tracked from the egg to the death of the adults, considering the larval stages distinction as well. Besides development and mortality, egg production over temperature has been recorded. The dataset was first analysed according to life tables studies; then, we also estimated the biological parameters of the most common equations describing development, mortality, and fertility involved in physiologically-based model applications. The results confirmed and extended the information on the thermal response already present in the literature, but with reference to a population adapted to warmer climates. The species successfully developed from egg to adult at 13–29 °C, while between 6–9 and 29–33 °C the development was limited to L2/L3 stages. Optimal temperatures are around 26–28 °C, depending on the life stage. This study provides one of the complete overviews of the thermal response of D. suzukii, which is available in the current literature, and opens the door to more accurate modelling frameworks. [ABSTRACT FROM AUTHOR]

The invasive alien stink bug Bagrada hilaris (Burmeister) (Hemiptera: Pentatomidae), native to eastern‐southern Africa and central‐southern Asia, poses significant economic threats to agroecosystems due to its polyphagous diet with a preference for brassicaceous crops. Current control methods using broad‐spectrum insecticides are expensive and often result in significant negative ecological impacts, as well as posing a health risk to consumers. This study provides a detailed description of the mating behavior of B. hilaris, with the aim to ascertain whether substrate‐borne vibrations have a role in premating phases. Such knowledge may contribute to the development of alternative biorational control techniques employing vibrational strategies. Virgin adults were tested individually or in pairs on different substrates, that is, a loudspeaker membrane and a bean plant. Vibrations emitted by males and females were recorded using a laser Doppler vibrometer, and the following spectral and temporal parameters were analyzed: fundamental frequency, emission time, repetition time, and signal modulation. Three distinct types of vibration emitted by males and females were identified: a male vibrotype (MV‐1), a female vibrotype (FV), and a copula signal exclusively emitted by males (MS‐2). MV‐1 and FV were emitted prior to genitalia contact, whereas MS‐2 was emitted within the mounting and engagement phases. Statistical analysis revealed significant transitions in behavioral phases for couples that achieved mating. By analyzing the walking behavior, there was an inverse relationship between motility and signal emission when comparing the two sexes, which suggests that males might engage in a form of searching behavior. These findings provide insight into the crucial role of vibrational communication to achieve mating in B. hilaris. [ABSTRACT FROM AUTHOR]

Drosophila suzukii poses a significant threat to berry fruits with its uncontrolled spread. Essential oils (EOs) have emerged as potential bioinsecticides due to their natural origin, mode of action, and biodegradability. Although EOs show potential for use in agriculture due to ecotoxicologically favourable characteristics, additional research is required to enhance their effectiveness, stability, and application for practical implementation in pest management. The primary objective of this research was the development of a bioinsecticide formulation based on a combination of three EOs – Pelargonium graveolens, Anethum graveolens, and Pinus sylvestris followed by the assessment of formulated bioinsecticide physicochemical properties. Using a two-choice bioassay, this study aimed to evaluate the effects of formulated bioinsecticides on D. suzukii, regarding their insecticidal properties through oviposition deterrence. The developed formulation exhibited favourable physicochemical properties and demonstrated a decrease in the number of larvae in fruits. Bioinsecticides present an environmentally friendly approach to pest control. However, further research and development are imperative to fully exploit their potential for effective crop protection in the field, followed by comprehensive research to evaluate the potential side effects on natural enemies, ensuring that their implementation doesn't harm beneficial organisms and maintain ecological equilibrium. [ABSTRACT FROM AUTHOR]

Aspergillus species create major postharvest problems due to the food losses caused by their mere presence and the hazardous mycotoxins they produce, such as aflatoxin B1 (AFB1) and ochratoxin A (OTA). These mycotoxins are mainly produced by A. flavus and A. carbonarius, respectively. In this study, we developed a rapid detection method for the two aforementioned species based on loop-mediated isothermal amplification (LAMP). The primers were designed to target genes belonging to the mycotoxin clusters pks and aflT for A. carbonarius and A. flavus, respectively. Result visualization was carried out in real time via the detection of fluorescent signals. The method developed showed high sensitivity and specificity, with detection limits of 0.3 and 0.03 pg/reaction of purified DNA of A. carbonarius and A. flavus, respectively. The assays were further implemented on inoculated nuts, including pistachios and almonds, after one-step crude DNA extraction. These tests revealed a detection level of 0.5 spore/g that shows the effectiveness of LAMP as a rapid method for detecting potentially toxigenic Aspergillus spp. directly in food. The validation of the assays included tests on a larger scale that further confirmed their sensitivity and specificity, as well as enabling the production of ready-to-use LAMP prototype kits. These kits are easy to use and aim to simplify the screening of food samples in order to monitor the presence of specific Aspergillus contaminations. [ABSTRACT FROM AUTHOR]

The spotted wing drosophila (SWD), Drosophila suzukii Matsumura (Diptera: Drosophilidae), is an invasive polyphagous pest of soft-skinned fruit that has started to threaten small fruit production in Europe since 2008. High reproductive capacity, short generation time, and difficulties in visualizing early damage contribute to its rapid spread. Currently, the control strategy against D. suzukii mostly relies on treatment with synthetic insecticides. Keeping in mind that this pest causes the greatest damage during the harvesting period, control using chemicals is not recommended due to the increased risk of high pesticide residue levels in the fruit. With the aim of reducing the use of insecticides, there is a need for developing an environmentally safer way of control. Alternative solutions could rely on the use of essential oils (EOs), which can be used in conventional and organic production systems. Four essential oils, geranium (Pelargonium graveolens), dill (Anethum graveolens), Scots pine (Pinus sylvestris), and bergamot (Citrus bergamia), were assessed for their insecticidal effects using four different tests (contact toxicity, fumigant-contact toxicity, repellent effect, and multiple-choice tests). The EOs applied were dissolved in acetone at three different concentrations. The most promising one was the geranium essential oil, which had the best effect in all conducted tests, even at the lowest applied concentration. Geranium oil caused very high mortality (95%), even at the lowest concentration applied, after 24 h in the fumigant-contact test, and it caused a mortality of over 85% in the contact test. It was also noticed that geranium demonstrated a deterrent effect by repelling females from laying eggs for four days after at the lowest applied concentration. Scots pine and dill EOs have moderate to strong effects in most tests. The mortality of 100% was achieved for the highest applied concentration in the fumigant-contact and contact tests. Bergamot EO did not have any significant insecticidal activity. Geranium, Scots pine, and dill have great potential to be used as an environmentally friendly way of controlling D. suzukii as they exhibit deterrent, repellent, and insecticidal effects. [ABSTRACT FROM AUTHOR]

Simple Summary: When an alien species reaches a new environment, the natural enemies present in that habitat might fail to regulate its population as they might not be host-adapted. Hence, the best solution might be the use of alien biological control agents that are co-evolved with the exotic pest in question. This is the case of Halyomorpha halys, which is native to Asia and has recently invaded Europe and the Americas. Trissolcus japonicus and Trissolcus mitsukurii are among its main parasitoids. Adventive populations of the latter were found in Northern Italy, suggesting its employment within augmentative biological control. Homologous programs with T. japonicus are already ongoing in Italy. This procedure implies releasing the parasitoid to increase its population and spread to new areas invaded by H. halys. However, a fundamental aspect that must be investigated is the risk-assessment beforehand, i.e., the systematic process of identifying the hazard associated with such a procedure. In this context, the preference of T. japonicus and T. mitsukurii between two stinkbugs was evaluated in this study. We found that T. japonicus preferred the naturally released traces of H. halys while T. mitsukurii exhibited a higher preference for the natural and synthetic chemical cues of N. viridula. Trissolcus mitsukurii and Trissolcus japonicus are two Asian egg parasitoids associated with different pentatomids such as Halyomorpha halys. Adventive populations of T. mitsukurii were found in Northern Italy, suggesting its employment as a biological control agent (BCA) against H. halys. Nevertheless, to reduce the latter's population, T. japonicus was released in Italy. Releasing an exotic parasitoid requires investigating the interaction between the BCA and the environment to avoid negative impacts on the entomofauna of the new habitat. Trissolcus mitsukurii is mainly associated with Nezara viridula in its native area. Therefore, we investigated and compared the ability of female T. mitsukurii and T. japonicus to distinguish between naturally released cues of H. halys and N. viridula. A single parasitoid was exposed to contact kairomones of both pests to evaluate its modifications in orthokinetic and locomotory behaviour. The behaviour of female T. mitsukurii was also tested on synthetic compounds simulating the cues of the two pentatomids. When naturally released cues were used, T. japonicus preferred the traces of H. halys, while T. mitsukurii preferred N. viridula's cues. Moreover, the attraction of T. mitsukurii to N. viridula's cues was confirmed with synthetic cues. Additional studies are needed to judge if this parasitoid can be used as a BCA. [ABSTRACT FROM AUTHOR]

Background: Drosophila suzukii is a highly destructive pest species, causing substantial economic losses in soft fruit production. To better understand migration patterns, gene flow and adaptation in invaded regions, we studied the genetic structure of D. suzukii collected across Italy, where it was first observed in 2008. In particular, we analysed 15 previously characterised Simple Sequence Repeat (SSR) markers to estimate genetic differentiation across the genome of 278 flies collected from nine populations. Results: The nine populations showed high allelic diversity, mainly due to very high heterozygosity. The high Polymorphism Information Content (PIC) index values (ranging from 0.68 to 0.84) indicated good discrimination power for the markers. Negative fixation index (FIS) values in seven of the populations indicated a low level of inbreeding, as suggested by the high number of alleles. STRUCTURE, Principal Coordinate and Neighbour Joining analysis also revealed that the Sicilian population was fairly divergent compared to other Italian populations. Moreover, migration was present across all populations, with the exception of the Sicilian one, confirming its isolation relative to the mainland. Conclusions: This is the first study characterising the genetic structure of the invasive species D. suzukii in Italy. Our analysis showed extensive genetic homogeneity among D. suzukii collected in Italy. The relatively isolated Sicilian population suggests a largely human-mediated migration pattern, while the warm climate in this region allows the production of soft fruit, and the associated D. suzukii reproductive season occurring much earlier than on the rest of the peninsula. [ABSTRACT FROM AUTHOR]

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Simple Summary: The spotted-wing Drosophila suzukii is an invasive fruit fly that causes high levels of damage to cherry fruits, which are, economically, a very important crop in the Puglia region. This pest infests mature fruits which are close to harvest, and when additional treatments are not allowed due to residue problems. The effect of infestation is a prolonged post-harvest time and up to 100% crop loss according to our field monitoring. The objective of our study was to find an effective post-harvest management of such infestations. We determined the growth rate of larval D. suzukii in infested fruits which were stored at low temperatures or treated with CO2 at low or room temperature; such post-harvest treatments were also tested in terms of the fruit quality at the end of the storage time, with respect to untreated infested fruits. When fruits were stored at low temperature in the presence of CO2 a consistent inhibition of larval growth was observed, with no apparent decrease of fruit quality parameters. After one month of storage, the quality parameters of treated, infested fruits were similar to the quality parameters of newly harvested fruits and non-infested fruits. Efficient strategies are required in sweet cherry fruits to control the spotted wing drosophila (SWD), Drosophila suzukii, due to its adverse economic effect on farmers. Cold storage (CS) and storage with elevated carbon dioxide (CO2) are environmentally safe approaches for the pest control of stored fresh fruit. These strategies are effective in controlling a wide variety of insect species, without allowing toxic compounds to accumulate. The purpose of this study was to assess the effectiveness of a post-harvest application of CO2 treatment at 50%, cold treatment at 4 °C (CT), and a combination of both (CO2-CT) in controlling the early stages of SWD within four cultivars of freshly harvested cherry fruit, namely "Burlat-Bigarreau", "Giorgia", "Ferrovia", and "Lapins". In addition, an evaluation of the quality attributes of the cherries (skin firmness, berry firmness, strong soluble material, and titratable acidity) was carried out at harvest and after 10 and 20 days of storage. All treatments significantly reduced the rate of emergence of SWD when compared to the control (untreated cherry at 24 °C), and 100% SWD mortality was obtained in Burlat-Bigarreau (CO2-CT). In addition, over the entire storage time, the quality parameters were preserved in the samples stored at 4 °C and in the samples with combined treatments in comparison with the control. [ABSTRACT FROM AUTHOR]

The olive fruit fly, Bactrocera oleae, is considered the main olive pest worldwide, and has been the target of biological control programmes through the release of the braconid parasitoid Psyttalia concolor. Laboratory tests were performed to evaluate the influence of distance from the host on parasitisation, placing larvae of the substitute host Ceratitis capitata at seven distances (0, 0.5, 1, 1.5, 2, 2.5, 3 mm) and four different time periods (7, 15, 30, 60 min). Moreover, field collected olives of Ogliarola Barese cultivar infested by B. oleae were exposed to P. concolor females to confirm its ability to parasitise B. oleae in small olives. Psyttalia concolor oviposition was inhibited at 2.5 and 3 mm due to the ovipositor length of the parasitoid females (2.7 mm). Hosts were easily parasitised at distances between 0 and 1.5 mm. The thin fruit pulp (up to 3.5 mm) of field collected olives allowed the parasitisation to occur also in mature fruits. At the best combination distance/time (0 mm, 30 min), tests performed with different larvae/parasitoid female ratio showed an increasing emergence of P. concolor (from 20% to 57%) with larvae/parasitoid ratio increasing from 0.11 to 0.74. The results of the present study might optimise the mass rearing of P. concolor, through a proper setting of its parameters, such as the host/parasitoid ratio, exposure distances, and interaction time. [ABSTRACT FROM AUTHOR]

Abstract: This work was conducted in an organic vineyard in Bari (South-Eastern Italy) to evaluate copper concentrations in grapes and wines of four local and international varieties (Chardonnay, Primitivo, Uva di Troia and Negroamaro) and to relate these contents to total and available copper concentrations in soil. Approximately 7.4kg/ha of copper were used in the trial year. Soil copper availability was higher in the 0–20cm (10.3%) than in the 20–40cm layer (4.7%). No copper phytotoxicity was observed on leaves. Copper residues on berries and in wines resulted below the maximum residue levels (MRLs). Concentrations in berries increased with applications number and varied according to the variety. Copper content in the white wine (Chardonnay) was higher with respect to red ones (Primitivo, Uva di Troia and Negroamaro). Results provided evidence that in the natural conditions typical of a Mediterranean environment, characterised by calcareous soils and a dry climate, the use of copper formulations in vineyards according to European legislation guidelines should not raise any concern with regards to human health. [Copyright &y& Elsevier]