Abstract Gonatopus chilensis (Olmi) (Hymenoptera: Dryinidae) is a host‐feeding parasitoid of delphacid planthoppers (Hemiptera: Auchenorrhyncha) with economic importance for maize crops. Several factors, including host acceptance, suitability, and defenses, significantly influence parasitoid–host dynamics and, consequently, the efficacy of parasitoids as biological control agents. Many biological attributes and traits of dryinids in general, and G. chilensis in particular, remain largely unexplored. This study aimed to evaluate the foraging behavior and effectiveness of G. chilensis and to identify biological factors influencing its performance when using the planthopper Delphacodes sitarea Remes Lenicov & Tesón (Hemiptera: Delphacidae) as hosts. Free‐choice and non‐choice tests conducted under laboratory conditions revealed that female G. chilensis could forage on host individuals ranging from the first nymphal instar to females of D. sitarea. Notably, the nymphal developmental stage of the host significantly impacted parasitoid effectiveness. Female parasitoids predominantly engaged in host feeding on small nymphs but preferred oviposition on larger nymphs and females. Furthermore, the size and likely the fitness of female parasitoid offspring increased with the instar or stage of the parasitized host. These findings suggest that the biological traits and effectiveness of G. chilensis are directly influenced by the developmental stage of the D. sitarea host.

Abstract Beauveria pseudobassiana S.A. Rehner & Humber (Hypocreales) and Metarhizium pingshaense Q.T. Chen & H.L. Guo (Hypocreales) are fungal pathogens that infect Phyllophaga larvae in the field. Previous laboratory bioassays showed less than 30% mortality in larvae inoculated with conidia of these pathogens, indicating strong resistance to fungal infection. However, injecting M. pingshaense blastospores directly into the larvae's hemocoel caused 100% mortality, suggesting external barriers may limit infection. As some insect‐associated bacteria can provide protection against invading pathogens, we hypothesized that bacteria associated with Phyllophaga larvae might offer such protection. We isolated bacteria from the cuticle of Phyllophaga larvae, identified morphotypes based on colony morphology and determined their antagonistic activity against B. pseudobassiana and M. pingshaense. Selected bacterial morphotypes were identified using partial 16S rRNA gene sequencing. Based on antagonism results, eight isolates were selected and their effect on the germination of conidia from both fungal species was evaluated. Finally, the mortality of antibiotic‐treated and untreated Phyllophaga polyphylla Bates (Coleoptera: Scarabaeidae) larvae was evaluated after inoculation with B. pseudobassiana and M. pingshaense. Of the 90 bacterial isolates obtained, all but two exhibited antagonistic activity against M. pingshaense, and 10 showed antagonism against B. pseudobassiana. Molecular analysis of selected morphotypes (62 isolates) revealed that the two most common genera were Acinetobacter (Moraxellales: Moraxellaceae) with 22 isolates and Serratia (Enterobacterales: Yersiniaceae) with 12 isolates. The remaining isolates were distributed among the families Flavobacteriaceae, Comamonadaceae, Enterobacteriaceae, Weeksellaceae and Pseudomonadaceae. Conidial germination of B. pseudobassiana was reduced to below 20% by most isolates, and only two allowed over 80% germination. For M. pingshaense, germination was suppressed to between 6% and 56% in most cases; only one isolate allowed 98% germination. When exposed to M. pingshaense, antibiotic‐treated larvae showed 68% mortality, whereas untreated larvae had only 26% mortality. In contrast, mortality from B. pseudobassiana was statistically similar between treated (23%) and untreated (7%) groups. Overall, our results suggest that bacteria can provide protection against M. pingshaense but not B. pseudobassiana.

Abstract Plasticity can help populations cope with environmental changes, namely by exploring various ecological niches. Addressing plasticity for nutritional responses in a range of fruit hosts potentially used by Drosophila may be essential in predicting the capacity of insects to colonize new environments or return to ancestral ones. Here, we test for differences in oviposition performance, reproductive success and juvenile viability in diverse host fruits in the colonizing species Drosophila subobscura (Collin 1936, Diptera: Drosophilidae) and compare them with those of the laboratory maintenance medium to which populations adapted for ~150 generations. We question as follows: Does D. subobscura show plasticity associated with various fruit hosts? Is performance better in the long‐term maintenance (control) medium? We observed a higher fecundity, reproductive success and juvenile viability of flies maintained in the fruit media versus the control, but no differences between fruits. Our experiment shows that long‐term laboratory populations of D. subobscura can still assess environmental cues of new substrates, allowing for flexible adaptive plasticity to occur through increased fecundity and reproductive success in fruit hosts relative to the control conditions. Importantly, this ability was not lost during long‐term evolution in a benign, homogeneous environment. Furthermore, the high performance across fruits reinforces its status as a generalist species and further attests to its potential to colonize various ecological settings.

Abstract This study explores the influence of pollinator diversity, behavior, and species interactions on seed yield of coriander (Coriandrum sativum L. [Umbelliferae Apiaceae]) over three consecutive years (2022–2024) at the Experimental Farm, ICAR‐VPKAS, Almora, Uttarakhand, India. A total of 46 insect pollinators from five orders were documented, with hymenopterans and dipterans emerging as the most diverse and dominant groups. Diversity and dominance indices, such as the Shannon and Simpson indices, were calculated to quantify the biodiversity, revealing a moderately diverse pollinator community with low species dominance. The open control treatments, where pollinators had unrestricted access to the flowers, recorded the highest seed yield, showing a 163% increase over closed controls, highlighting the critical role of insect pollinators in enhancing crop productivity. The synergistic interaction between Andrena spp. and Apis cerana indica Fabricius 1798 (Hymenoptera: Apidae) resulted in a significant yield enhancement of 117.1%, demonstrating the potential benefits of targeted pollinator management. Additionally, polyhouse studies utilizing A. c. indica showed that controlled pollination could achieve comparable yield improvements to field conditions, proving the feasibility of such approaches. Finally, the study highlights the importance of maintaining diverse pollinator communities and strategically leveraging species interactions to maximize coriander yield, offering valuable insights for sustainable agricultural practices.

Abstract Common gorse, Ulex europaeus L. (Fabaceae) is a serious invasive shrub of pastures, forest gaps, and natural areas in western North America. The seed weevil, Exapion ulicis (Forster) (Coleoptera: Brentidae) was introduced as a biological control organism at three locations in California and one location in Oregon from 1953 through 1956. To document its performance as a biological control organism, a survey of 11 gorse populations along a north–south transect was performed in 2021 and 2022. The seed weevil was recovered at all locations, but the intensity of attack (percentage of pods infested) varied from 2 to 88%. Various components of pod fecundity (pod length, number of ovules, seed set, number of mature and intact seeds) varied spatially. Seed set (mature seed‐to‐ovule ratio) ranged from 24 to 60% and production of mature seeds (prior to predation) ranged from 1.4 to 4.6 seeds per pod. When present, E. ulicis larvae destroyed 91% of seed in a pod. For infested pods, the number of weevils per mature seed was 1.72, with an average of 6.3 weevils and 3.3 mature seeds per pod. The number of intact seeds after predation averaged 0.3 seeds per pod. Mean seed loss due to E. ulicis ranged from 1 to 81% among locations and was closely related to the local intensity of attack. Oviposition by female E. ulicis targeted more fecund pods. Three parasitoids were recovered, with local parasitization rates of E. ulicis larvae ranging from 0 to 1.6%, suggesting that parasitoids do not limit population abundance of the seed weevil.

Abstract The spotted wing drosophila, Drosophila suzukii, is an invasive pest of soft‐skinned fruits. The efficacy of pesticides and repellents against this pest has often been evaluated in laboratory bioassays through the use of fresh fruits as a test subject. However, the use of fresh fruits may have several limitations, including variability in their attractiveness, high perishability, and the potential presence of agrochemical residuals. To address these challenges, this study aimed to assess the efficacy of artificial fruits produced from inexpensive, edible, and readily accessible ingredients as oviposition substrates for D. suzukii. Blueberry‐grape juice, blueberry‐apple juice, raspberry jam, strawberry jam, and D. suzukii solid artificial diet were used as food sources. Artificial fruits prepared with uncolored artificial diet were then colored using three different red edible colorings. Drosophila suzukii females were exposed to all artificial fruits, and the ovipositional responses of the pest were evaluated by counting the total number of eggs laid in food‐based substrates. Artificial fruits prepared with artificial diet and colored with red edible colorings were found to be the most attractive substrates to D. suzukii females, exhibiting an average number of eggs up to nine times higher than that of other tested ones. Our findings indicate that artificial fruits represent a viable alternative to fresh fruits for testing the ovipositional responses of D. suzukii under laboratory conditions, thereby facilitating the standardization of fruit‐making procedures.

Abstract We report a novel robust method for rearing two species of cynipid gall wasps, Diplolepis mayri (Schlechtendal) and Diplolepis rosae (Linnaeus) (both Hymenoptera: Diplolepididae), under controlled laboratory conditions. This study involved using five wild rose species (Rosa rubiginosa [L.], Rosa canina [L], Rosa gallica [L], Rosa spinosissima [L.], and Rosa arvensis [Huds]; Rosaceae) maintained under artificial lighting with L14:D10 (2023) and L16:D8 (2024) photoperiods, 60%–70% relative humidity, and a constant temperature of 22–23°C. Successful induction, development, and emergence of gall wasps were achieved over two consecutive years. Remarkably, a second generation of D. mayri emerged within the same year, a phenomenon not previously observed in outdoor nor laboratory settings. Our results show that D. mayri may be more suited for laboratory model studies than D. rosae. This technique provides a foundation for future studies on the ecology, evolution, and host–parasite interactions of cynipid wasps.

Abstract Wing geometric morphometrics is a widely used tool for taxonomic and ecological studies. The conventional method involves killing insects and cutting the wings for preparation on slides and microscope photography. In this work, we proposed an alternative method to avoid killing and wing cutting, using honey bees as model species. We validated three more sustainable practices: using a smartphone to photograph the wings instead of the microscope; analyzing images of wings left attached to the bees; and using live anesthetized bees without sacrificing them. The results of geometric morphometrics and statistical analyses demonstrated the validity of using the smartphone to capture wing images of adequate quality to correctly digitize the landmarks at the veins intersection. Wings left attached to the bees and photographed without any support were significantly different in shape from those cut and taped to a sheet of paper. Probably the position of the wings was not parallel enough to the smartphone, which caused image distortions. This problem was overcome by placing the wings in a homemade portable clamp to flatten them and keep them more parallel to the smartphone. In this way, the morphology of the wings left attached to the bees was equal to that of the cut wings. Lastly, analyses of wing images of anesthetized live bees showed no differences compared with those of cut wings. These results set the basis for the non‐destructive application of geometric morphometrics on museum specimens and for field applications on caught and released individuals, avoiding the unnecessary killing of insects.