Abstract Mosaic disease, caused by Cassava mosaic virus and transmitted by cassava whitefly, Bemisia tabaci (Gennadius; Hemiptera: Aleyrodidae), is the main threat to cassava production. Various genotypes with various degrees of resistance were employed to study the interactions between the whitefly and virus. These interactions included dispersal, feeding, fecundity, adult longevity and the life cycle. Virus acquisition in whiteflies altered their dispersal and settling behaviour. For the non‐viruliferous whiteflies that fed on resistant cassava genotypes, the speed of movement between leaves was higher compared to the viruliferous ones that fed on susceptible genotypes. Viruliferous whiteflies on susceptible genotypes fed more efficiently compared to non‐viruliferous ones on resistant genotypes, but fecundity was lowest in viruliferous whiteflies on resistant genotypes. The presence of virus in the system reduced adult longevity but extended the total life cycle. This study provides insights into how the virus modulates the behaviour and physiology/biology of the vector for enhanced transmissibility.

Abstract Insects use multiple body parts, not just their mouth, to taste. Whether a particular body part has a taste function can be determined by examining the morphology or electrophysiological response of its sensilla (sense organs) or by its behavioral response. This study investigated the taste response of each of the three pairs of tarsi, tibiae, femurs, as well as the antennae and wings, in house flies, Musca domestica L. (Diptera: Muscidae). This was done by measuring the proboscis extension response (PER), and in the case of the wings, also the grooming behavior. PER is a visible precursor to consumption. The fore, middle, and hind tarsi of both male and female house flies distinguished between sucrose solution versus water. The fore tibiae and femurs of females and the middle femurs of males also made this distinction. Of the body parts tested, the middle, and especially the fore, tarsi were the ones most responsive to sucrose. Contact of aristae (part of the antennae) did not elicit PER regardless of whether contact was with a toothpick that had been soaked in sucrose, water, or nothing. For both males and females, neither the proportion of flies exhibiting PER nor the duration of grooming was significantly affected by whether the anterior wing margin was contacted with a toothpick that had been soaked in sucrose, water, or a dry toothpick.

Abstract Social insects are known to have a complex and elaborate communication system. In termites, communication through chemical signals is paramount, as the soldiers and workers of the majority of species are blind and have cryptic habits. Despite this, knowledge about the role of foraging signals in termites is still scarce, especially in phylogenetically derived species. Here, we aimed to analyze the role of foraging signals in Nasutitermes corniger (Motschulsky, 1855) (Termitidae: Nasutitermitinae), including the effect of various glands and/or caste origins of foraging signals, the response of groups with various caste compositions, and the intercolonial perception of these signals. Specifically, we tested the following hypotheses: (i) rectal fluid and sternal gland extracts have diverse roles in perception, orientation, and acceptance by groups of N. corniger with distinct caste compositions; (ii) the behavior of N. corniger exposed to intercolonial foraging signals is not altered compared with intracolonial signals; and (iii) intercolonial foraging signals attract N. corniger. To do so, trailing behavior and attraction behavior bioassays were carried out in the laboratory. The sternal gland extract triggered the greatest trailing behavior among the foraging signals. Furthermore, the rectal fluid extract seems to elicit trail‐following behavior in N. corniger, whereas the sternal gland extract acts as a recruitment signal. Finally, the behavior and attractiveness of the intercolonial foraging signals were not different from that of the intracolonial signals. The results found in the present study increase the understanding of foraging chemical communication in Termitoidae and reveal the role of intercolonial signals in the attractiveness of groups of N. corniger.

Abstract Brown marmorated stink bug (BMSB), Halyomorpha halys Stal (Hemiptera: Pentatomidae), is a significant invasive agricultural pest affecting diverse crops globally. Halyomorpha halys rapidly invaded the Black Sea agricultural region of Türkiye, necessitating investigation of invasion pathways using complementary molecular approaches. We employed a novel approach on insect genetics—start codon targeted (SCoT) markers—to assess intraspecific genetic diversity among 71 BMSB specimens from 12 Turkish provinces and analyzed mitochondrial cytochrome c oxidase subunit I (COI) regions from nine specimens and integrating previously published data to construct a phylogenetic TCS network. SCoT markers revealed substantial genetic diversity (91.4% polymorphic fragments), identifying six distinct genetic clusters within Turkish populations. Analysis of molecular variance showed significant population structuring at the provincial level but limited differentiation regionally. The Western Black Sea region exhibited highest genetic diversity, with Trabzon identified as a variation hotspot. Conversely, COI‐based TCS analysis showed all Turkish specimens belonged exclusively to the dominant Hap_1 lineage prevalent in most invaded countries worldwide. The marker systems highlight improved resolution of SCoT markers in detecting recent genetic diversification not apparent through mitochondrial analysis alone. This novel genetic approach enhances understanding of BMSB invasion pathways in the Black Sea region of Türkiye. Understanding invasion dynamics and genetic variation with worldwide BMSB samples would provide crucial information for developing targeted management measures. Our results demonstrate the potential utility of SCoT markers for detecting intraspecific genetic diversity within regional insect populations. This preliminary assessment, based on 71 specimens for SCoT analysis and nine representative specimens for COI sequencing, provides foundational evidence for the superior resolution of SCoT markers in invasion genetics studies.

Abstract Prior damage can alter a plant's susceptibility to future herbivory and yield potential, which is mediated, in part, by the plant's ability to regrow and changes in nutritional content. In perennial sugarcane (Saccharum spp.), herbivory by lepidopteran stem borers early in a growing season can increase the probability of conspecific herbivory later in the crop year. However, it is unknown whether the effects of prior borer damage either to vegetatively propagated seed cane or to standing plants can impact conspecific herbivory or crop yield in subsequent crop years. Using a long‐term dataset and two field studies, we investigated the impacts of prior sugarcane borer (SCB; Diatraea saccharalis [F.]; Lepidoptera: Crambidae) damage on levels of conspecific damage across crop years. We also evaluated long‐term impacts of SCB damage on plant quantity and quality, aspects that may alter future herbivory and yield. We found that prior SCB damage to either seed cane or standing crops did not alter conspecific damage in subsequent crop years. This prior SCB damage also did not impact plant quality (fiber, sucrose, and carbon content). However, foliar nitrogen was lower in plots without SCB damage in the first year but damaged in the second crop year. Metrics of plant quantity (tiller emergence and aboveground biomass) and total sugar yield were not impacted by prior years' SCB damage. Taken together, our data indicate that although SCB herbivory can significantly increase conspecific herbivory and impact sugarcane plants within a crop year, these effects were not sustained post‐harvest following regrowth of aboveground biomass.

Abstract Lepidopteran insects are among the most significant crop pests in the Americas, causing extensive economic damage to sugarcane, tobacco, cotton, tomato, and corn crops. To improve biopesticide design for their control, it is essential to characterize the insect cuticle, which acts as a barrier against fungal infections, regulates compound permeation, and affects bioproduct adhesion. This study characterized the cuticles of Diatraea saccharalis (Fabricius) (Lepidoptera: Crambidae) and Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae) based on fatty acid composition, morphology, contact angle, adhesion and cohesion work, spreading coefficient, and surface free energy (polar and dispersive components). Diatraea saccharalis exhibited higher saturated fatty acid content, whereas H. zea showed greater polyunsaturated fatty acid levels. Morphologically, H. zea displayed more developed mandibles and ventral/dorsal spines compared with D. saccharalis. Water had the highest adhesion work on D. saccharalis, whereas formamide liquid showed the highest adhesion on H. zea. Dimethyl sulfoxide and ethylene glycol spread more effectively on both species. Overall, D. saccharalis exhibited hydrophilic cuticle properties, whereas H. zea was more hydrophobic. This study provides foundational insights into cuticular characteristics, enabling the development of biopesticides with improved efficacy for pest control in agricultural systems.

Abstract Sub‐lethal exposure to an elevated temperature can improve some traits, including longevity and/or early fecundity (EF), a phenomenon known as hormesis. Here, sub‐lethal and repeated exposures to heat were applied in two sibling species, Drosophila buzzatii (Patterson and Wheeler) and Drosophila koepferae (Fontdevila and Wasserman) (both Diptera: Drosophilidae), to assess any possible heat‐induced effects on longevity and EF at benign temperature. In addition, heat‐knockdown resistance was measured in each species. As in previous studies, D. koepferae was found to be a short‐lived species as compared to other Drosophila species, including D. buzzatii. Heat‐knockdown resistance in females was higher in D. buzzatii than in D. koepferae, but no significant difference between species was found in males in a mixed‐sex environment. Hormesis in longevity was substantial in D. buzzatii, but no hormesis was found in the longevity of D. koepferae. Relative early fecundity (REF) strongly increased due to heat stress in females of D. koepferae, whereas no changes were found for this trait in D. buzzatii. These results show that the hormetic response to repeated exposures to heat can differ between very closely related species that share the same thermal environments in sympatric arid populations where there is no place to hide, differentially affecting traits of the well‐known trade‐off between longevity and EF. Taken together, the results from this and previous studies suggest that, in contrast to D. buzzatii, the short‐lived D. koepferae appears to be the fly that not always can extend its longevity by exposures to an elevated but sub‐lethal temperature. Interestingly, in contrast to longevity, EF in D. koepferae and not in D. buzzatii was found to increase due to the exposure to elevated temperature, revealing differences between these sibling species.

Abstract Microbial biological control agents are garnering widespread interest for managing insect pests, and their usage in agriculture offers a viable alternative to synthetic insecticides. In this study, cauliflower plants (Brassica oleracea var. botrytis L., Brassicaceae) inoculated with endophytic fungi Aspergillus flavus (Link) (Eurotiales) and Aspergillus niger (van Tieghem) (Eurotiales) isolated from Acacia arabica (Willd) (Fabaceae) were used to assess their insecticidal potential against Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) larvae. Inoculation of cauliflower with both endophytes resulted in significant mortality, reduced adult emergence, prolonged development period, and negatively affected the reproductive potential of S. litura. The nutritional physiology of the larvae fed on the endophyte‐infected leaves was significantly affected. The relative growth and consumption rates of the S. litura larvae decreased as compared to the control. The fungal endophytes suppressed the activity of some digestive and detoxifying enzymes. The larvae fed on leaves inoculated with fungal endophytes showed a significant decrease in total hemocyte count, as well as in the activity of phenoloxidase and lysozyme. This study showed that artificial inoculation of plants with fungal endophytes would help in reducing pest incidence and thus could be integrated in future pest management programs.