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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]

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