In this study, we aimed to investigate the effects of five different commercially available essential oils; aloe vera, borage, cacao, horse chestnut and nettle seed oils against egg, nymphal and pupal stages of Bemisia tabaci Gennadius and its important natural enemies namely, Encarsia formosa Gahan, Eretmocerus eremicus Rose and Zolnerowich, Macrolophus pygmaeus Rambur, Nesidiocoris tenuis Reuter, and Orius laevigatus Fiber. This study was conducted under laboratory conditions in 2021 at Bursa Uludag University, Turkey. The essential oil solutions were applied at %0.125, 0.25 and 0.5 doses and mortality rates were noted after 24, 48 and 72 hours of essential oils application. As a result, it was determined that the insect species most affected by the plant oils were the predators, the immature stages (egg, nymphal and pupal) of whitefly and the parasitoid species, respectively. Borage and horse chestnut oils showed high effects (100%) on predatory adults after 24 hours. It was determined that all N. tenuis and M. pygmaeus adults died after 48 hours in the trial. The egg, nymphal and pupal stages of B. tabaci were most affected by plant oils, respectively. B. tabaci eggs and pupal stages were the most affected from cacao oil with a mortality rate of 100%. Moreover, nymphal stage of B. tabaci was the most affected by horse chestnut oil with a mortality rate of 100% after 72 hours. Parasitized pupae were found to be the least affected individuals in the trial. Aloe vera oil was the least effective essential oil in the experiment. Eggs and nymphal stages of B. tabaci, O. laevigatus, E. formosa and E. eremicus were affected by aloe vera oil with mortality rates of 53.33%, 46%, 53%, 46% and 36%, respectively. Horse chestnut and cacao oils were harmful to the immature stages (egg, nymphal and pupal) of B. tabaci and all predator adults (M. pygmaeus, N. tenuis, O. laevigatus), but they had slightly harmful on parasitoid species in the experiment.

Root-emitted volatile organic compounds (VOCs) play a critical role in below-ground ecological interactions by mediating communication between plants, pests, and their natural enemies. This study investigates the chemotactic behavior of three slug-parasitic nematode species—Phasmarhabditis papillosa, Oscheius myriophilus, and Oscheius onirici—in response to four carrot (Daucus carota) root-derived VOCs: α-pinene, terpinolene, bornyl acetate, and 2-ethyl-1-hexanol. Using a modified Petri dish assay, infective juveniles (IJs) were exposed to each compound across four concentrations (pure, 1000 ppm, 10 ppm, and 0.03 ppm), and their directional movement was quantified using a chemotaxis index (CI). The results revealed strong species-specific and concentration-dependent patterns. O. myriophilus exhibited the highest motility and repellency, particularly toward bornyl acetate and terpinolene, indicating its potential for use in VOC-guided biocontrol strategies. O. onirici showed moderate but consistent attraction to most VOCs, while P. papillosa exhibited generally weak or repellent responses, especially at higher concentrations. None of the compounds tested functioned as strong attractants (CI ≥ 0.2), suggesting that plant-derived VOCs alone may not be sufficient to direct nematode recruitment under field conditions. However, their integration with other biotic cues could enhance nematode-based “lure-and-infect” systems for sustainable slug control in carrot cropping systems.

Monilinia laxa and Colletotrichum fioriniae are major fungal pathogens causing brown rot and anthracnose in stone fruits and shell fruits, leading to significant economic losses. Chemical fungicides are widely applied but can result in resistance development, environmental contamination, and food safety concerns. Biological control using entomopathogenic bacteria (EPB) of the genus Photorhabdus has emerged as an eco-friendly alternative. This study evaluated the in vitro antifungal activity of selected Photorhabdus species (P. kayaii 1723B, P. temperata 3017, P. cinerea 3086, P. laumondii 3196, and P. thracensis 3210) against M. laxa (M3) and C. fioriniae (VV081) using drop-to-drop confrontation and poisoned agar assays. Effects of fermentation time, preparation mode (original vs. centrifuged and filtered), and concentration (5, 10, 20%) were examined. Species-specific inhibition was observed, with Median Inhibition Index values indicated relatively higher antifungal activity for P. thracensis 3210 against M. laxa (0.718) and C. fioriniae (0.552), followed by P. cinerea 3086 (0.643 and 0.552) and P. kayaii 1723B (0.629 and 0.541). Fermentation time and preparation mode influenced antifungal activity in a strain-dependent manner, with longer fermentation periods and original culture preparations generally showing stronger inhibitory trends. Higher concentrations, especially 20%, were often associated with increased inhibition, although the magnitude of these effects varied among strain–pathogen combinations. Overall, these findings demonstrate that the strain- and pathogen-specific nature of antifungal responses in Photorhabdus, supporting their potential as components of targeted biological control strategies rather than uniform broad-spectrum agents.

Stored product pests, such as Sitophilus oryzae and Oryzaephilus surinamensis , pose significant threats to global grain storage. Plant extracts rich in phenolics offer environmentally friendly alternatives to synthetic pesticides for managing these pests. This study is the first to evaluate the biological activity of shade-dried (GS) and oven-dried (ES) water extracts of Trachystemon orientalis against S. oryzae and O. surinamensis . Phytochemical analysis revealed that the GS extract exhibited higher total phenolic content and antioxidant capacity compared to the ES extract. Specifically, the GS extract contained higher concentrations of abscisic acid (3346.76 mg/10 ⁶ g dried matter (dm)) and caffeic acid (1666.17 mg/10 ⁶ g dm), whereas the ES extract was richer in o - and p -salicylic acid, p -coumaric acid, and rosmarinic acid. Orientation assays conducted at four concentrations (62.5–500 ppm) revealed time- and concentration-dependent changes in the distribution of adults between treated and control compartments. After 120 h, the presence of O. surinamensis at the GS 500 ppm site decreased to 44% (G = 36, p ≤ 0.05), while S. oryzae presence dropped to 33% (G = 31.4, p ≤ 0.05). Furthermore, higher concentrations of the GS extract significantly reduced F1 adult emergence for both pests ( p < 0.05, Two-Way ANOVA). These findings suggest that T. orientalis extracts, particularly GS, represent promising environmentally friendly alternatives to chemical pesticides for the management of stored product pests. The efficacy of these extracts is closely associated with their higher phenolic content and specific bioactive compounds.

The experiment was conducted in the Entomology Laboratory of the Department of Plant Protection, Faculty of Agriculture, Bursa Uludag University in October 2020 – May 2021. The aim of the study was to determine the toxic effects of five essential oils on five important biological control agents. The commercially obtained essential oils of carrot, wintergreen, ginger, wormwood, and clove were shown to be toxic to biological control agents Orius laevigatus, Nesidiocoris tenuis, Macrolophus pygmaeus, Encarsia formosa, and Eretmocerus eremicus in three doses: 0.125, 0.25, and 0.5 v/v. After 3 hours, for the predator O. laevigatus, the most effective (100%) oils were wintergreen and clove oils, while for N. tenuis, the most effective were wintergreen (100%), wormwood (100%), and clove (97%) ones. After 24 hours, ginger oil showed a 95% mortality effect on M. pygmaeus. The parasitoids E. formosa and E. eremicus were less affected by the oils, only wormwood oil had a slightly deleterious effect on the parasitoids E. formosa and E. eremicus (mean 53% and 43%, respectively).

Our study reports the first occurrence of Zaprionus indianus Gupta, 1970 (Diptera: Drosophilidae) in Hungary, representing the northernmost European record of this thermophilic species. Specimens were captured in October 2023 during a large-scale Drosophila suzukii (Matsumura, 1931) (Diptera: Drosophilidae) monitoring program conducted in sweet cherry orchards in north-central Hungary. A total of five individuals (one female and four males) were caught at two different orchards 1 km apart, using modified pan and bottle traps baited with apple cider vinegar-based lures. No specimens were detected in the previous year (2022) or the following year (2024), which may indicate a transient population, though further monitoring would be required to confirm the lack of establishment. Although the overwintering of the species appears unlikely in Hungary, climate change may facilitate its future range expansion. Our findings highlight the importance of continuous monitoring of invasive drosophilids in Central Europe for better understanding their establishment potential and agricultural risks.