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Maize production faces persistent threats from maize diseases and pests (MDPs) throughout its growth cycle, posing substantial risks to food security. However, understanding the spatio-temporal dynamics of MDPs occurrences on a regional scale has remained elusive due to a lack of continuous observation data. This study curated a comprehensive dataset spanning two decades, from 1999 to 2018, across six key maize planting regions in China [Spring sown area in Northern China (1-NC), Summer sown region in Huang-Huai-Hai Plain (2-HHP), Southwest Mountain Maize Region (3-SM), Southern Hilly Maize Region (4-SH), Northwest Irrigated Maize Region (5-NI), and Maize Region in Qinghai-Tibet Plateau (6-QTP)]. The average extent of MDP occurrence in 1-NC and 2-HHP exceeded that in other regions over the two-decade period. Furthermore, the occurrence of MDPs exhibited a substantial increase in 1-NC, 2-HHP, 3-SM, 4-SH, and 5-NI over the same period. Meanwhile, the average occurrence intensity of MDPs in 2-HHP surpassed that in other regions. Notably, maize leaf blight and the Asian maize borer emerged as predominant diseases and pests in 1-NC, 2-HHP, 3-SM, 4-SH, and 5-NI. A bivariate trend analyses highlighted a notable increase in the species count for both the extent and intensity of MDP occurrences, including double-spotted leaf beetle in 1-NC, and cotton bollworm in 2-HHP. This extensive, long-term analysis offers a foundation for devising comprehensive strategies for MDP control on a national scale, enabling the formulation of tailored forecasting and control measures across six planting regions. [Display omitted] • The mean extent and intensity of maize diseases and pests (MDPs) were determined across six maize planting regions. • Bivariate trends in the occurrence area and intensity of MDPs were assessed across six maize planting regions. • Thirty predominant species of MDPs were identified in China. • The occurrence of MDPs in China exhibited a substantial increase over the two-decade period. • Maize leaf blight and the Asian maize borer emerged as predominant MDPs. [ABSTRACT FROM AUTHOR]

Prenyltransferases play a pivotal role in the isoprenoid biosynthesis and transfer in insects. In the current study, two classes of prenyltransferases (MhieFPPS1 and MhieFPPS2, MhiePFT-β and MhiePF/GGT-α) were identified in the leaf beetle, Monolepta hieroglyphica. Phylogenetic analysis revealed that MhieFPPS1, MhieFPPS2, MhiePFT-β and MhiePF/GGT-α were clustered in one clade with homologous in insects. Moreover, MhieFPPS2 lacked one aspartate-rich motif SARM. Molecular docking and kinetic analysis indicated that the (E)-GPP displayed higher affinity with MhieFPPS1 compared to DMAPP within the binding pocket containing metal binding sites (MG). The other class of prenyltransferases (MhiePFT-β and MhiePF/GGT-α) lack the aspartate-rich motif. Docking results indicated that binding site of MhiePFT-β involved divalent metal ions (Zn) and bound farnesyl or geranylgeranyl. In vitro , only recombiant MhieFPPS1 could catalyze the formation of (E)-farnesol against different combination of substrates, including IPP/DMAPP and IPP/(E)-GPP, highlighting the importance of SARM for enzyme activities. Kinetic analysis further indicated that MhiePFT-β operated via Zn2+-dependent substrate binding, while MhiePF/GGT-α stabilized the β-subunit during catalytic reaction. These findings contribute to a valuable insight in to understanding of the mechanisms involved in the biosynthesis and delivery of isoprenoid products in beetles. • Two classes of prenyltransferases are identified in Monolepta hieroglyphica. • MhieFPPS1 shows multiple catalytic functions, while the motif SARM plays a significant role. • Farnesyltransferases is involved in farnesyl or geranylgeranyl transfer. • A putative metabolic pathway for the de novo synthesis and transmission of isoprenoids in beetles was constructed. [ABSTRACT FROM AUTHOR]

Insect pests pose a global threat to crop yield. Biological control by natural enemies aims to reduce pest damage in a sustainable way. Cereal leaf beetles (CLB; Oulema spp.) are major pests in small-grain cereals. We studied the effect of natural enemies on CLB damage and its consequences on yield within its native distribution area in Europe. In exclusion cage experiments and by documenting a naturally occurring CLB damage gradient, we found that CLB damage reduced yield, but natural enemy action reduced the damage by CLB. Comparing exclusion and open treatments on artificially CLB-infested plants, plants accessible to natural enemies had 30% less leaf damage. CLB damage significantly affected yield parameters. Thousand grain weight was 22–29% less in maximum leaf damage scenarios. In the damage gradient field, maximal infestation reduced grain yield by 52%. However, maximal damage occurred only on a few plants and over small areas. In natural infestation cases, the number of CLB larvae per plant had a median of zero; nevertheless, there were more than 35 larvae on 10% of the plants. Patchiness explained 40% of CLB damage variance. Damage was unevenly distributed; as a result, thousand grain weight decreased only by 1.6% for 75% of the plants but by 18% for 10% of the plants. In the natural damage gradient, the estimated yield loss for the entire field was 16% due to CLB. Skewed CLB distribution may lead to perceptible yield losses locally, but natural enemies may limit overall damage to the crop. [Display omitted] • Allowing natural enemy access reduced leaf damage by cereal leaf beetle (CLB) larvae. • Such leaf damage could cause significant quantitative and qualitative losses in yield. • Under natural infestations, 75% of the plants had 3 or fewer larvae, causing only 1.6% yield loss. • Limited yield losses in unsprayed fields, at least in part, are due to natural enemies. • We recommend early detection of heavily infested areas instead of blanket spraying. [ABSTRACT FROM AUTHOR]

Sowing of wildflower strips has been integrated in agri-environment schemes of several European countries. Their beneficial effects on natural enemies of pest insects are well documented but (1) the desired spill-over into crop fields has not always been demonstrated, and (2) the need to adapt sown mixtures to regional climatic differences has been rarely addressed. We set up a multi-site experiment in different French climatic regions to compare effects of a wildflower strip with a grass mixture and spontaneous vegetation. The design included five regions, three to five fields per region and the three strip treatments being repeated in each field. We tested strip treatment effects on vegetation (plant species richness, plant and flower cover) and on natural enemies (hoverflies, ladybirds, aphid predation). In a subset, we further analysed the spill-over into winter wheat fields including natural enemies and pest insects (cereal aphids, leaf beetles). The wildflower strip mixture developed well in all regions and increased plant species richness and flower cover compared with grass strips and spontaneous vegetation. We found a corresponding higher hoverfly abundance and aphid predation in wildflower strips that were consistent in all regions, whereas ladybird abundance was not affected. A significantly higher hoverfly abundance, aphid predation and aphid parasitism in wheat fields close to wildflower strips indicated a spill-over. No corresponding margin treatment effects were observed for aphid and leaf beetle abundance in the field. A multivariate analysis comparing the influence of climate and vegetation parameters showed that floral cover better explained variation in natural enemy abundance and predation than climate. Our results demonstrated that similar mixtures of native plants can be used over large climatic gradients to improve biocontrol. Further research is needed to improve spill-over into crop fields and to obtain consistently strong effects in different climate zones. [ABSTRACT FROM AUTHOR]

The fauna of Eumolpinae of New Caledonia has been under intense scrutiny in over the last decade and numerous species are being described on a regular basis. In this study, we revise in detail the group of Colaspis laboulbenei Montrouzier, 1861, currently in the genus Dematochroma Baly, 1864, using a combined approach with DNA-based phylogenies and the study of morphology and species distributions. Several relevant systematic conclusions result from this revision: (1) recognition of the monophyletic group around Dematochroma laboulbenei ; (2) recognition of an important morphological character, namely the presence or absence of a dorsal groove on pygidium, separating two narrowly parapatric lineages in this group; (3) reversal of a long-held synonymy with D. laboulbenei and reinstatement of Thasycles cordiformis Chapuis, 1874 stat. rev. ; (4) restitution of Thasycles Chapuis, 1874 stat. rev. based on phylogenetic and taxonomic arguments to delimit this group of species; (5) transfer of Dematochroma fusca Jolivet, Verma & Mille, 2007, D. laboulbenei and Dematochroma panieensis Jolivet et al., 2007 to Thasycles ; and (6) description of seven new species, including Thasycles castaneus Gómez-Zurita n. sp. , Thasycles compactus Gómez-Zurita n. sp. , Thasycles grandis Gómez-Zurita n. sp. , Thasycles magnus Gómez-Zurita n. sp. , Thasycles puncticollis Gómez-Zurita n. sp. , Thasycles tenuis Gómez-Zurita n. sp. , and Thasycles variegatus Gómez-Zurita n. sp. A species identification key and a brief discussion about the systematics and potential factors affecting the diversification and distribution of Thasycles are provided. [ABSTRACT FROM AUTHOR]

The genus Erynephala Blake, 1970 is reviewed based on linear morphometry and a morphological study. A cladistic analysis of the genus based on morphological characters is also presented. The results demonstrate that Erynephala brighti Blake, 1970 is synonym of Erynephala maritima (LeConte 1865), and that the "race" of E. maritima , originally described as Monoxia puncticollis var. texana Schaeffer, 1932 is recognized as a different species: Erynephala texana (Schaeffer 1932) stat. nov.. The cladistic analyses revealed that Erynephala is monophyletic, forms three clades: ((E. maritima + E. texana) + (Erynephala morosa + Erynephala puncticollis)) + Erynephala interrupta , and it is close related to Monoxia LeConte, 1865 species. We also provide redescriptions and photographs of adult males and females, in addition to distribution maps. [ABSTRACT FROM AUTHOR]

[Display omitted] • Taumacera viridis species group from Vietnam is revised. • Taumacera phucuoca sp. nov. Phu Quoc National Park is described. • Colour photographs of habitus and body details are presented. The species of Taumacera viridis species–group from Vietnam are revised. Four species are recognized. Taumacera indica (Jacoby, 1889), T. occipitalis (Laboissière, 1933) and T. variceps (Laboissière, 1933), are redescribed. Taumacera phuquoca sp. nov. from Phu Quoc National Park (southern Vietnam) is described. An identification key is provided for all Vietnamese species. www.zoobank.org/urn:lsid:zoobank.org:pub:396862F9-8A47-4101-A27C-CD0625E68FA1. [ABSTRACT FROM AUTHOR]

Mate choice and male–male combat over successful mating often cause disproportionate exaggeration of male trait relative to body size. However, the exaggeration is often not the only trait involved with male–male combat and mate choice: suites of co-expressed traits may function together as a coordinated unit. When this occurs, dimorphism may be expected for these additional, non-exaggerated, structures. S. femorata males have disproportionately large hind-legs used in male–male combat over females. During the fights, fore- and mid-legs are used to keep males in positions where advantageous for leverage. Because use of the exaggerated hind-legs is coordinated with the other legs, they will coevolve as a functional unit. Here, we show that 1) S. femorata has sexual size differences in all three legs; 2) males show positive allometry in the relative sizes of all three legs; and 3) microstructures of tarsi on the fore- and mid-legs are also sexually dimorphic. Despite these differences in the tarsal microstructure, 4) adhesion forces of the tarsi had no sexual difference in flat surface. The microstructure would be specialized on attaching elytra surface. These results suggest that the three pairs of legs function together during fighting behavior, with hind-legs employed primarily for fighting, and the fore- and mid-legs functioning to grip females, keeping males positioned on the back of the female during combat. • Sagra femorata males have disproportionately large hind-legs used in male–male combat. • Males have positive allometry in not only hind-leg but also fore- and mid-leg size. • Microstructures of tarsi of male fore- and mid-legs appear specialized for the combat. • Specialized microstructures did not affect adhesion force on flat substrate. • All legs function together during combat for fighting and keeping male position. [ABSTRACT FROM AUTHOR]

The seed beetle, Callosobruchus maculatus (Coleoptera: Chrysomelidae), is a severe cosmopolitan pest of various stored legumes. Since no parthenogenesis has been reported in the genus Callosobruchus , here we report the evidence of a rare event of deuterotokous parthenogenesis in this species. Interestingly, 11.11% of females out of 600 tested virgin females were capable of reproducing by parthenogenesis. Unfertilized-eggs developed into viable adults with a sex ratio of 1:1. Parthenogenetically-produced males and females could successfully copulate and generate the next generation. They achieved statistically the same total immature development, adult longevity, egg number, and hatchability as sexually produced progeny. However, none of the 60 female offspring produced via parthenogenesis were capable of reproducing by parthenogenesis. Mating disruption and sterile insect technique for pest control could not be efficient in insects with parthenogenetic reproduction because parthenogenesis will compensate for males' absence by producing viable male and female offspring, saving species from possible extinction in the future. Therefore, these findings are important not only for considering in the Integrated Pest Management programs but also from an evolutionary perspective. Biodiversity and genetic differentiation among the current worldwide distribution of C. maculatus could be the origin of this facultative deuterotokous parthenogenesis evolution. [ABSTRACT FROM AUTHOR]

Plant cell wall-associated polygalacturonase-inhibiting proteins (PGIPs) are widely distributed in the plant kingdom. They play a crucial role in plant defense against phytopathogens by inhibiting microbial polygalacturonases (PGs). PGs hydrolyze the cell wall polysaccharide pectin and are among the first enzymes to be secreted during plant infection. Recent studies demonstrated that herbivorous insects express their own PG multi-gene families, raising the question whether PGIPs also inhibit insect PGs and protect plants from herbivores. Preliminary evidence suggested that PGIPs may negatively influence larval growth of the leaf beetle Phaedon cochleariae (Coleoptera: Chrysomelidae) and identified BrPGIP3 from Chinese cabbage (Brassica rapa ssp. pekinensis) as a candidate. PGIPs are predominantly studied in planta because their heterologous expression in microbial systems is problematic and instability and aggregation of recombinant PGIPs has complicated in vitro inhibition assays. To minimize aggregate formation, we heterologously expressed BrPGIP3 fused to a glycosylphosphatidylinositol (GPI) membrane anchor, immobilizing it on the extracellular surface of insect cells. We demonstrated that BrPGIP3_GPI inhibited several P. cochleariae PGs in vitro, providing the first direct evidence of an interaction between a plant PGIP and an animal PG. Thus, plant PGIPs not only confer resistance against phytopathogens, but may also aid in defense against herbivorous beetles. [ABSTRACT FROM AUTHOR]

• A world catalogue of Sermyloides. • A key of worldwide Sermyloides. • Two new species of Sermyloides from China. In this study, a species catalogue of Sermyloides , including 42 species, is given. Two new species are described: Sermyloides wuyiensis sp. nov. from Fujian, China and Sermyloides bipunctatus sp. nov. from Chongqing, China. A key to species, photographs of aedeagus, habitus of new species and habitus of 14 species of Chinese holotypes are provided. www.zoobank.org/urn:lsid:zoobank.org:pub:820BDA9F-633B-49D8-B5F0-45610E622C9A. [ABSTRACT FROM AUTHOR]

Parthenium hysterophorus L. is considered globally as one of the most troublesome weeds, which has invaded non-cropped as well as cropped lands in many tropical and sub-tropical countries including India. Biological control using the Mexican beetle (Zygogramma bicolorata Pallister) among other agents, has been considered most successful in India. In the present study, models were developed using climatic indices (minimum temperature, maximum temperature, rainfall and relative humidity) as independent variables to determine the suitable sites for the establishment of Z. bicolorata. Regression approach for model building revealed 79.6% concordance, 20.0% discordance, and 0.4% tie between predicted probabilities and observed responses whereas, decision tree using J48 algorithm classified 81.7% instances correctly which helped to frame the rules for predicting the establishment of Z. bicolorata. Based on these rules, it was concluded that a site experiencing climate with indices values of average minimum temperature 24.2–26.2 °C and rainfall 191.2–257.3 mm during July to October would be highly suitable for setting up the Z. bicolorata population in the region. These models might be useful to decide the most suitable sites for release and establishment of Z. bicolorata in India as well as in other parts of the world with similar climatic conditions. • Parthenium hysterophorus L. is one of the most troublesome weeds globally. • Biological control of P. hysterophorus using Zygogramma bicolorata Pallister has been considered most successful in India. • Regression approach and decision tree using J48 algorithm were used to model the establishment of beetle using climatic variables. •. Minimum temperature and its interaction with rainfall and relative humidity were found to be important climatic variables • These models might be useful for the selection of most suitable sites for release and establishment of Z. bicolorata. [ABSTRACT FROM AUTHOR]

Sequestration of plant secondary metabolites is a detoxification strategy widespread in herbivorous insects including not only storage, but also usage of these metabolites for the insects' own benefit. Larvae of the poplar leaf beetle Chrysomela populi sequester plant-derived salicin to produce the deterrent salicylaldehyde in specialized exocrine glands. To identify putative transporters involved in the sequestration process we investigated integral membrane proteins of several tissues from juvenile C. populi by using a proteomics approach. Computational analyses led to the identification of 122 transport proteins in the gut, 105 in the Malpighian tubules, 94 in the fat body and 27 in the defensive glands. Among these, primary active transporters as well as electrochemical potential-driven transporters were most abundant in all tissues, including ABC transporters (especially subfamilies B, C and G) and sugar porters as most interesting families facilitating the sequestration of plant glycosides. Whereas ABC transporters are predominantly expressed simultaneously in several tissues, sugar porters are often expressed in only one tissue, suggesting that sugar porters govern more distinct functions than members of the ABC family. The inventory of transporters presented in this study provides the base for further functional characterizations on transport processes of sequestered glycosides in insects. Image 1 • Proteomics identified transport proteins in several tissues of juvenile C. populi. • ABC transporters and sugar porters are of interest for sequestration of salicin. • ABC transporters are often expressed simultaneously in several tissues. • In general, sugar porters seem to be more tissue-specific than ABC transporters. [ABSTRACT FROM AUTHOR]

The cowpea weevil, Callosobruchus maculatus (F.), is a storage pest that mainly infects cowpea (Vigna unguiculata (L.) Walp), spending part of its life cycle inside the grains. Depending on the region, the decrease in cowpea production by cowpea weevils can exceed 70% during a six-month storage period. This study investigated the fumigant effect of lemongrass essential oil (Cymbopogon citratus (DC.) Stapf.) and citral on the reproductive cycle, sexual behavior, lipid composition and the enzymatic activity of biotransformation enzymes in cowpea weevils. Mortality (61.43%, 85.00%), oviposition (4.00%, 29.51%) and emergence (10.32%, 1.51%) were observed for lemongrass essential oil and citral treatments, respectively. Exposure to lemongrass essential oil led to changes in behavior for both sexes, decrease in triacylglycerol content of virgin and mated females, and reduction of the activities of acetylcholinesterase (females and males) and β-esterase (females). These changes may affect the survival, energy resource transfer during oogenesis and oviposition, which are likely mechanisms involved with essential oil toxicity. Image 1 • C. maculatus is susceptible to fumigant effect of lemongrass essential oil and citral. • Lemongrass essential oil affects C. maculatus sexual behavior and lipids content. • Xenobiotic enzymes may be a target involved with lemongrass essential oil toxicity. • Effect of lemongrass essential oil gives new perspectives to the C. maculatus control. [ABSTRACT FROM AUTHOR]

β-Glucosidases play an important role in the chemical defense of many insects by hydrolyzing and thereby activating glucosylated pro-toxins that are either synthesized de novo or sequestered from the insect's diet. The horseradish flea beetle, Phyllotreta armoraciae , sequesters pro-toxic glucosinolates from its brassicaceous host plants and possesses endogenous β -thioglucosidase enzymes, known as myrosinases, for glucosinolate activation. Here, we identify three myrosinase genes in P. armoraciae (PaMyr) with distinct expression patterns during beetle ontogeny. By using RNA interference, we demonstrate that PaMyr1 is responsible for myrosinase activity in adults, whereas PaMyr2 is responsible for myrosinase activity in larvae. Compared to PaMyr1 and PaMyr2 , PaMyr3 was only weakly expressed in our laboratory population, but may contribute to myrosinase activity in larvae. Silencing of PaMyr2 resulted in lower larval survival in a predation experiment and also reduced the breakdown of sequestered glucosinolates in uninjured larvae. This suggests that PaMyr2 is involved in both activated defense and the endogenous turnover of sequestered glucosinolates in P. armoraciae larvae. In activity assays with recombinant enzymes, PaMyr1 and PaMyr2 preferred different glucosinolates as substrates, which was consistent with the enzyme activities in crude protein extracts from adults and larvae, respectively. These differences were unexpected because larvae and adults sequester the same glucosinolates. Possible reasons for different myrosinase activities in Phyllotreta larvae and adults are discussed. [Display omitted] • Phyllotreta armoraciae leaf beetles possess three different myrosinases. • Different enzymes are responsible for myrosinase activity in larvae and adults. • The beetle myrosinases differ in their substrate specificities. • Myrosinase activity protects larvae against a generalist predator. • Myrosinases metabolize sequestered glucosinolates in uninjured larvae. [ABSTRACT FROM AUTHOR]

Systena frontalis (F.) (Coleoptera: Chrysomelidae) is an important pest of many ornamental plants in container nurseries. Adult S. frontalis cause feeding damage on leaves and affected plants are not marketed. Systena frontalis adults are currently managed using insecticides, especially neonicotinoids, and growers are seeking alternative options as customers demand neonicotinoid-free plants after concerns associated with nontarget exposure to pollinators. Barrier fences could be an alternative tactic to protect high-value crops, such as panicled hydrangea (Hydrangea paniculata Siebold), from invading S. frontalis adults in container nurseries. Thus, the objective of this study was to determine the effect of overhang barrier fence using with and without insecticide-impregnated-netting on adult S. frontalis infestation and feeding damage on panicled hydrangea. In 2021 and 2022, a study using an overhang exclusion fence was conducted in a container nursery in Georgia, USA. The treatments were: 1) deltamethrin-impregnated enclosed barrier, 2) nontreated enclosed barrier, and 3) no barrier. Four containers of panicled hydrangea were placed in the center of each experimental plot. Both deltamethrin-impregnated and nontreated enclosed barrier treatments reduced the incidence and severity of adult feeding damage on the panicled hydrangea than no barrier treatment. There was no difference between deltamethrin-impregnated and nontreated enclosed barrier treatments. The results suggest that overhang barriers can protect container plants from invading adult S. frontalis. • Systena frontalis is a serious pest on ornamental plants in container nurseries in the eastern USA. • Overhang barrier fence reduced adult S. frontalis infestation and damage on panicled hydrangea. • Feeding damage was similar between deltamethrin-impregnated and nontreated fence barrier. [ABSTRACT FROM AUTHOR]

Agri-environment measures such as flower strips are considered fundamental instruments to reduce farmland biodiversity loss. Their effect on associated ecosystem services, such as biocontrol of crop pests, has received increased attention in recent discussions on the ecological intensification of agriculture, to create a win-win situation for biodiversity and production. However, studies of flower strips are rarely compared to the status quo, namely permanent field margins. We assessed the impact of two different field margin types (pre-existing grassy field margins vs. perennial flower strips) and distance decay effects from the field margins towards field centres on two major cereal pests (cereal leaf beetles and cereal aphids), their natural enemies (predators and aphid parasitoids) and crop yield on five conventional farms in Germany. Proximity to both types of field margin enhanced the enemy-to-pest ratio for cereal leaf beetles but not for aphids. However, the parasitism rate for aphids was higher next to grassy strips than next to flower strips. Yield also tended to be higher adjacent to flower strips (although not significantly) and showed no variation with distance to the field margin. Our findings paint a more nuanced picture than most previous studies: whilst field margins generally had a positive impact on one of the studied biocontrol agents, flower strips do not outperform the standard grassy margins currently in place. To promote biocontrol services, we recommend protecting existing, permanent grassy strips through the EU Common Agricultural Policy as a cost-effective alternative to flower strips. • Field margins boosted biocontrol of cereal leaf beetles, but not aphids, in conventional cereals. • Ratio of enemies to cereal leaf beetles declined with distance from the margin. • Flower strips did not outperform grassy strips for most biocontrol parameters. • Yield tended to be higher adjacent to flower strips, but not significantly. [ABSTRACT FROM AUTHOR]

Flower strips are advocated as a strategy to promote beneficial insects as well as the services they deliver to adjacent crops. Flower strips have, however, often been developed separately for pollinators and natural enemies and, additionally, little consideration has been given to effects on insect herbivores. We sampled insect herbivores, their natural enemies and parasitism of pest eggs using vacuum sampling, sticky cards and egg cards in nine pairs of bee-attractive wildflower plantings and control field borders, as well as in adjacent tomato and watermelon crop fields in Yolo County, California 2015–2016. Control field borders had a higher total number of herbivores on sticky traps than did wildflower plantings, a pattern that was driven by more aphids, hoppers, psyllids and whiteflies, whereas wildflower plantings had more lace bugs and Lygus bugs. The total number of herbivores in the adjacent crop fields did not differ between treatments, but there were more leaf beetles near (at 10 m but not 50 m from) wildflower plantings. Control field borders had a higher total number of predators, driven by more big-eyed bugs, lady beetles and minute pirate bugs, whereas spiders were more common in wildflower plantings. The total number of predators in adjacent crop fields was, however, higher in those next to wildflower plantings, which was driven by more minute pirate bugs. Parasitoid wasps were more common in wildflower plantings and at 10 m but not 50 m into adjacent crop fields. Stink bug egg parasitism rate did not differ between treatments, either in the borders or in the crop fields. In conclusion, wildflower plantings clearly affect the insect herbivore and natural enemy community, but do so in a highly taxon-specific manner, which can lead to both positive and negative outcomes for pest control as a result. • Effects of wildflower plantings on herbivores and natural enemies were taxon-specific. • •Wildflower plantings promoted natural enemies in adjacent crop fields. • No consistent effect on herbivores and egg parasitism in adjacent crop fields. [ABSTRACT FROM AUTHOR]

Abstract The North American common ragweed, Ambrosia artemisiifolia , which produces highly allergenic pollen, is invasive in different parts of the world, including Europe. In 2013, common ragweed in northern Italy was found attacked by another accidentally introduced species, the North American leaf beetle Ophraella communa , which is used for biological control of common ragweed in China. Since the establishment of O. communa , ragweed pollen concentrations in northern Italy have significantly dropped. Here we set out to estimate the potential economic benefits of establishment of O. communa in the Rhône-Alpes region in south-eastern France, where detailed data on the economic impact of common ragweed are available. Extrapolating from the change in airborne ragweed pollen concentrations in the Milan area, we estimated that establishment of O. communa in the Rhône-Alpes region will reduce the number of days with ragweed pollen concentrations at which sensitive people express symptoms by 50% and the medical costs due to common ragweed by 5.2–6.8 M € annually. Our findings suggest that investments of public funds are justified to conduct a complete assessment of the potential risks and benefits associated with the accidental establishment of O. communa in Europe. [ABSTRACT FROM AUTHOR]

Highlights • Coleoptera abundance and diversity were similar in all fuel reduction treatments. • Chrysomelidae was significantly more abundant in mechanical and burn treatments. • Staphylinidae abundance was significantly lower in mechanical and burn treatments. • Fire reduced the canopy cover and increased plant cover on the forest floor. • Repeated application of fuel reduction techniques can alter beetle abundances. Abstract Coleoptera are important components of forest ecosystems and can be affected by forest management schemes aimed at limiting fuel build-up. Our research objective was to determine if repeated applications of fuel reduction treatments resulted in changes in abundance or diversity of beetle (Coleoptera) families, genera, and species within upland mixed hardwood forests in the southern Appalachians Mountains, North Carolina, USA. We established three replicate blocks (∼56 ha) and split each block into four fuel reduction treatments. Treatments included prescribed burning, mechanical felling, a combination of prescribed burning and mechanical felling, and a control (i.e. , no fuel reduction techniques applied). We implemented treatments multiple times (2 mechanical thinnings and 4 prescribed burns) over the course of a 15-year period. Using pitfall and colored pan traps, we captured 7037 coleopterans comprised of 62 families over a three-year period. Total coleopteran abundance and diversity were similar across all treatments; however, some beetle families, genera, and species responded to treatments. Nitidulidae were significantly more abundant within controls compared to all other treatments in 2015, whereas Mordellidae generally had higher abundances in mechanical and burns compared to mechanical in 2015 and mechanical and controls in 2016. Chrysomelidae was significantly more abundant in mechanical and burns compared to all other treatments over the entire duration of the study. However, Staphylinidae abundance was significantly lower in mechanical and burns compared to the other treatments. Numerous genera and species also showed variable treatment-level responses. Burn treatments killed some mature trees and reduced forest canopy cover, resulting in higher light availability and thereby greater herbaceous cover and diversity on the forest floor. This vegetation in the understory of burned treatment units may be partially responsible for many of the treatment-level responses of beetle taxa we documented. This study took place after several rounds of fuel reduction techniques were applied over a 15 year period. Some beetle abundance responses were immediate; whereas other groups seemed to be influenced by the application of treatments over time, highlighting the need to examine long-term responses to forest management practices. [ABSTRACT FROM AUTHOR]

Abstract This study analyzes the distributions in Sub-Saharan Africa of the endemic and sub-endemic flea beetle genera, Calotheca Heyden and Blepharidina Bechyné, this latter subdivided in the two subgenera, Blepharidina s.str. and Afroblepharida Biondi & D'Alessandro. To compare and correlate their pattern of geographic range and the current distribution of the terrestrial ecosystems occurring in the Afrotropical Region, 588 presence records were considered, 61 for Afroblepharida , 93 for Blepharidina and 434 for Calotheca. Afroblepharida , mainly occurring in the region of Africa between the 20th parallel N and the equator, has a clear preference (62%) for desert and semi-desert habitats, while Calotheca , widespread in the southern Africa, mainly in the eastern belt between the 20° and 40° meridian at E of Greenwich, Arabian Peninsula and Israel, results comparatively more mesophilous, preferring savannas (54%), and forests (37%). Finally, Blepharidina , mainly occurring in the region between the equator and the Tropic of Cancer, takes an intermediate position between Afroblepharida and Calotheca , with preference for savannah (47%), forest (32%), and semi-desertic (21%) habitat. Presence records were also used to build Ensemble models for current and past climatic conditions (Last Glacial Maximum and Mid-Holocene). The results, also in this case, show a clear separation between Afroblepharida and Blepharidina in central African's predicted suitable areas, as well as for Calotheca , which is predicted to occur especially in southern Africa. Post-modeling analyses on predicted suitable areas reinforced the patterns of habitat preference observed through occurrence localities and showed that the two genera once shared a large area, mainly composed by savannas, which progressively shrunk and changed to more desertic conditions. [ABSTRACT FROM AUTHOR]

Abstract Determining responses of organisms to changing temperatures is a research priority, as global warming threatens populations and ecosystems worldwide. Upper thermal limits are frequently measured as the critical thermal maximum (CT max), a quick bioassay where organisms are exposed to increasing temperatures until individuals are not able to perform basic motor activities such as walking or flying. A more informative approach to understand organism responses to global warming is to evaluate how vital rates, such as growth or survival, change with temperatures. The main objectives of this study are: (1) to determine if factors affecting insect vital rates such as diet quality, developmental temperatures or acclimation also affect CT max and (2) to determine if vital rates of different life stages (i.e. , insect larvae or adults) display different responses to temperature changes. If different life stages have particular thermal requirements, this may indicate different susceptibility to global warming. This study focuses on Cephaloleia belti (Coleoptera: Chrysomelidae), a tropical insect currently expanding its diet to an exotic host plant. We determined how high and low-quality diets (i.e., native vs novel host), as well as exposure temperatures affect CT max of adult beetles. We also estimated larval and adult survival when feeding on high and low quality host plants, when exposed to temperatures typical of the elevational distribution of this species, or when exposed to projected temperatures in 100 years. We did not detect an effect of diet quality or acclimation on CT max. However, larvae and adults had different thermal requirements. CT max is not affected by previous diet or acclimation as an adult. We propose that to understand processes involved in the adaptation and persistence of ectotherm populations in a warming world, studies must explore responses beyond CT max , and focus on the response of vital rates to changing temperatures. Highlights • The critical thermal maximum (CT max) is used to estimate the upper thermal limits or organisms. • Insect CT max is a qualitative parameter not affected by diet or thermal experience. • However, diet and temperature affect vital rates such as growth and survival. • Global warming research must focus on vital rates rather than CT max estimates. [ABSTRACT FROM AUTHOR]

Although the importance of parasitoids as biocontrol agents has long been recognized, systematic studies of the physiological mechanisms are scarce, especially in those parasitoids that are able to successfully invade their hosts by activating host immune responses. This study explored this phenomenon by investigating the effects of ovarian fluid, venom and egg surface characteristics of Tetrastichus brontispae (Hymenoptera: Eulophidae) on host immunity. The results showed that the injection of venom alone induced higher phenoloxidase activity, while a mixture of ovarian plus venom fluids provoked higher granulocyte and plasmatocyte spreading ratios, highlighting the role that egg surface characteristics may play in successful parasitism. After thorough investigation, the presence of a hemomucin homologue was documented on the egg surface (which was named Tetrastichus brontispae adipocyte plasma membrane associated protein-like, TbAPMAP-like), while the absence of polydnaviruses, fibrous layers and virus-like filaments was confirmed. The higher encapsulation index of eggs incubated with TbAPMAP-like polyclonal antibody demonstrated the protection of the protein against encapsulation. These results contribute to our understanding of the mechanisms used by endoparasitoids to evade encapsulation during the early parasitism stage while enriching our knowledge of local active regulatory mechanisms. It is likely that this is the first study to determine the egg protective properties of TbAPMAP-like in host-parasite systems. [ABSTRACT FROM AUTHOR]

We asked whether ambient temperatures can affect morph frequencies within a subarctic population of the polymorphic leaf beetle Chrysomela lapponica through thermal melanism and/or developmental plasticity. Body temperature increased faster in beetles of dark morph than in beetles of light morph under exposure to artificial irradiation. Dark males ran faster than light males in both field and laboratory experiments, and this difference decreased with increasing ambient air temperature, from significant at 10 °C to non-significant at 20 °C and 26 °C. On cold days (6–14 °C), significantly more dark males than light males were found on their host plants in copula (40.8% and 27.3% respectively); on warm days (15–22 °C) this difference disappeared. Light females produced twice as many eggs as dark females; this difference did not depend on the ambient temperature. The proportion of dark morphs in the progenies of pairs with one dark parent was twice as high as that in the progenies of pairs in which both parents were light, and this proportion was greater when larvae developed at low (10 and 15 °C) than at high (20 and 25 °C) temperatures. We conclude that low temperatures may increase the frequencies of dark morphs in C. lapponica populations due to both the mating advantages of dark males over light males and developmental plasticity. Variation in frequencies of low-fecund dark morphs in the population, caused by among-year differences in temperature together with density-dependent selection, may contribute to the evolutionary dynamics of the colour polymorphism and may influence abundance fluctuations in these leaf beetle populations. [ABSTRACT FROM AUTHOR]

During winter, many organisms conserve resources by entering dormancy, suppressing metabolism and biosynthesis. The transition out of winter dormancy to summer activity requires a quick reversal of this suppression, in order to exploit now-favorable environmental conditions. To date, mechanisms by which winter climate variation affects this transition remains unelucidated. Here we experimentally manipulated snow cover for naturally overwintering montane leaf beetles (Chrysomela aeneicollis), and profiled changes in gene expression during the transition out of dormancy in spring. Upon emergence, beetles up-regulate transcripts associated with digestion and nutrient acquisition and down regulate those associated with lipid metabolism, suggesting a shift away from utilizing stored lipid and towards digestion of carbohydrate-rich host plant tissue. Development of digestive capacity is followed by up-regulation of transcripts associated with reproduction; a transition that occurs earlier in females than males. Snow manipulation strongly affected the ground thermal regime and correspondingly gene expression profiles, with beetles showing a delayed up-regulation of reproduction in the dry compared to snowy plots. This suggests that winter conditions can alter the timing and prioritization of processes during emergence from dormancy, potentially magnifying the effects of declining snow cover in the Sierra's and other snowy mountains. [Display omitted] • We compared global gene expression of montane leaf beetles as they emerged from dormancy. • Females prioritized upregulation of genes involved in reproduction and digestion. • Males also prioritized digestion, but reproduction was delayed by several days. • Winter snow cover impacted the timing of upregulated post-dormancy processes. [ABSTRACT FROM AUTHOR]

This study was focused on the synthesis of silver nanoparticles using Acalypha hispida leaf extract and the characterization of the particles using UV–Vis spectroscopy, XRD, FT-IR, and TEM. The results showed the formation of silver nanoparticles, crystalline in nature, with an average size of 20–50 nm. The leaf extract components were analyzed with GC–MS and exhibited a high content of Phytol (40.52%), n -Hexadecanoic acid (9.67%), 1,2,3-Benzenetriol (7.04%), α- d -Mannofuranoside methyl (6.22%), and d -Allose (4.45%). The optimization and statistical investigation of reaction parameters were studied and maximum yield with suitable properties of silver nanoparticles was obtained at leaf extract volume (0.5 mL), the concentration of silver nitrate (1.75 mM), and reaction temperature (50 °C). The method of detecting Mn 2+ ions using the colloidal silver nanoparticles was discussed. The minimum and maximum detection limit were found to be 50 and 200 µM of Mn(II) ions, respectively. Thus, the obtained results encourage the use of economical synthesis of silver nanoparticles in the development of nanosensors to detect the pollutants present in industrial effluents. [ABSTRACT FROM AUTHOR]

The area of agriculturally used land and following to that the use of pesticides are steadily increasing. Insecticides do not only reduce pest organisms on crops but can also affect non-target organisms when present in sublethal concentrations in the environment. We investigated the effects of an exposure to sublethal pyrethroid (lambda-cyhalothrin) concentrations, at doses 20 and 60 times lower than the LC 50 , respectively, on reproductive traits and adult cuticular hydrocarbon (CHC) profiles of a leaf beetle ( Phaedon cochleariae Fabricius). Furthermore, we tested for effects on growth and antennae symmetry of the offspring generation that was not exposed to the insecticide. Sublethal insecticide concentrations decreased the egg number produced by the adults and the hatching rate. Moreover, the chemical phenotype (CHC profile) of adults was altered in dependence of the insecticide treatment, with sex-specific effects. In the unexposed offspring of insecticide-exposed parents, a prolonged development time and a fluctuating asymmetry of the females' antennae were detected, revealing transgenerational effects. The insecticide effects on the CHC profiles of the parental generation might have been caused by changes in CHC precursors, which were potentially induced by the insecticide treatment of the insect diet. Such altered CHC pattern may have implications for intraspecific communication, e.g., in mate choice, as well as in an interspecific way, e.g., in interactions with other arthropod species. The observed detrimental transgenerational effects might be explainable by a reduced investment in the offspring, maternal transfer or epigenetic processes. An asymmetry of the antennae may lead to defects in the reception of chemical signals. In conclusion, the results disclose that, besides detrimental (transgenerational) effects on reproduction and development, an exposure to sublethal insecticide concentrations can impair the chemical communication between individuals, with impacts on the sender (i.e., the CHC profile) and the receiver (i.e., caused by asymmetry of the antennae). [ABSTRACT FROM AUTHOR]

Phenotypic expressions of insects are strongly dependent on various external and internal factors, like diet or density and age or sex. However, environmental effects on the behavioural phenotype and repeatability are rather unexplored for holometabolous insects in their larval stage. We examined the effects of the food environment (young versus old cabbage leaves) and previous test experience on growth and behaviour of Phaedon cochleariae larvae. A more nutritious diet, i.e., young leaves, had beneficial consequences on larval growth. Contrary to findings on adults, the behaviour of larvae was neither consistent over time nor across contexts, thus larvae did not show personality. Furthermore, larval behaviour was shaped independent of the diet, pointing to a stage-dependent receptivity towards diet conditions in this species. Besides, larval activity was significantly influenced by former test experience, with naïve larvae being more active than previously tested larvae. In general, in insects memories in an olfactory or sexual behaviour context can lead to behavioural responses later in life. Mechanisms of memory-learning should be further explored in different contexts in insects. Overall, the present study reveals that growth-related traits are diet-dependent and that the activity of a holometabolous larva is shaped in dependence of its previous test experience. [ABSTRACT FROM AUTHOR]

The species of Charaea Baly, 1878 from Vietnam, Laos, Thailand, Myanmar and continental Malaysia are revised. Nine species are recognized; apart of Ch. coomani (Gressitt and Kimoto, 1963) and Ch. kelloggi (Gressitt and Kimoto, 1963) from Vietnam, seven species are described: Ch. bifurcatum sp. nov. (Malaysia), Ch. houaphanicum sp. nov. (Laos, China: Guangdong), Ch. jaromiri sp. nov. (Thailand, Laos), Ch. langeri sp. nov. (Myanmar), Ch. latha sp. nov. (Laos), Ch. pytlaki sp. nov. (Thailand), and Ch. zaki sp. nov. (Myanmar). Charaea coomani species group is redefined. Colour photographs of habitus and male genitalia, as well as drawings of both male and female genitalia, are presented. [ABSTRACT FROM AUTHOR]

Chrysomela populi (Coleoptera: Chrysomelidae) is the most abundant and most important pest species that causes damage to poplar trees. Members of the family Chrysomelidae are frequently infected by protist pathogens but no neogregarine has been reported to date at the species level. In the present study we identify a new neogregarine pathogen from the chrysomelid C. populi. The infection was observed in the Malpighian tubules of adult beetles. A reddening of the Malpighian tubules was the most distinctive symptom of the infection. Single fusiform oocysts (9.8 × 4.7 μm) were formed within a gamontocyst. The polar plugs were very thin, varying from 380 to 525 nm in thickness. The oocyst wall was smooth and also quite thin (90–120 nm). Morphological and ultrastructural characteristics of the pathogen indicate that the described neogregarine in C. populi is clearly different from known Ophryocystis species which infect coleopterans. Therefore, the neogregarine pathogen was determined to be a newly discovered species and named Ophryocystis anatoliensis sp. nov. [ABSTRACT FROM AUTHOR]

The variety of chemical compounds produced by members of Annonaceae exhibiting wide activity against pest organisms makes this family an interesting source for insecticidal compound identification. Accordingly, this study first aimed to evaluate the lethal and sublethal effects of ethanolic extracts of different parts of Duguetia lanceolata St.-Hil. against Zabrotes subfasciatus (Boheman) (Coleoptera: Chrysomelidae: Bruchinae), the primary pest of stored beans in tropical regions. Based on a screening bioassay, the ethanolic extract from D. lanceolata leaves was selected for chemical partitioning due to its high bioactivity against the weevil. The hexanic partition of the ethanolic leaf extract caused 98% mortality of Z. subfasciatus adults in a residual contact bioassay and completely eliminated the number of eggs per sample. Chromatography subfraction Flh2-5, a hexanic partition of D. lanceolata leaves, resulted in 100% mortality of Z. subfasciatus adults. An aromatic compound (2,4,5-trimethoxystyrene) and a mixture of sterols [(campesterol (8.44%) + stigmasterol (12.37%) + sitosterol (79.19%)] were isolated from subfraction Flh2-5 using various chromatographic procedures. The aromatic compound resulted in 60% weevil mortality, and the steroid mixture applied at 75 mg kg −1 promoted 28% mortality; in contrast, the positive control (K-Obiol ® 2P, deltamethrin 2 g a.i./kg) at 375 mg kg −1 resulted in 100% mortality. Moreover, both 2,4,5-trimethoxystyrene and K-Obiol ® 2P completely prevented oviposition on bean samples, demonstrating that, similar to a deltamethrin-based formulation, 2,4,5-trimethoxystyrene is able to act as a grain protector. Therefore, the aromatic compound and mixture of isolated sterols from D. lanceolata may be suitable management tools of stored-product pests and promising sources of insecticidal molecules with both lethal and sublethal effects on Z. subfasciatus . [ABSTRACT FROM AUTHOR]

Insects live in a three-dimensional space, and need to be able to attach to different types of surfaces in a variety of environmental and behavioral contexts. Adult leaf beetles possess great attachment ability due to their hairy attachment pads. In contrast, their larvae depend on smooth pads to attach to the same host plant. We tested friction forces generated by larvae and adults of dock leaf beetles Gastrophysa viridula on different rough surfaces, and found that adults generate much higher attachment to various substrates than larvae, but are more susceptible to completely losing attachment ability on surfaces with “critical” roughness. Furthermore, sex-specific setal morphology has the effect that attachment forces of male adults are generally higher than those of females when adjusted for body weight. The results are discussed in the context of development, ecology, and changing behavioral strategies of successive life stages. [ABSTRACT FROM AUTHOR]

Two-year field experiments were carried out in four farms in Northern Italy with the aim of developing an agroecological approach to manage flea beetles, Chaetocnema tibialis (Illiger) and Phyllotreta spp. (Chevrolat) (Coleoptera: Chrysomelidae) on sugar beet by using trap crops. In each farm, two treatments were compared: i) trap crop, in which was a plot of sugar beet with an edge consisting of a mixture of Sinapis alba (L.) and Brassica juncea (L.); ii) control, which was a plot of sugar beet with bare soil at the field margin. An overall significant reduction (≈40%) in flea beetle damage was detected on sugar beets grown nearby trap crops in comparison with control plots. Furthermore, in the trap crop treatment, flea beetle damage varied with the distance from the trap crop border, as the highest damage was detected at 2 m from the border, whereas lower damage was found at increasing distances from the trap crop. Trap cropping has potential as an ecological way to reduce early sugar beet damage and the need for insecticide applications. • Flea beetles are key pests of sugar beets that damage mainly early-stage plants. • Several Brassicaceae are more attractive for flea beetles than sugar beets. • Brassicaceae trap crops significantly decreased flea beetle damage on sugar beets. • Trap crops seem promising to reduce reliance on insecticides for flea beetle management. [ABSTRACT FROM AUTHOR]

Divergence in chemosensory traits has been posited as an important component of chemosensory speciation in insects. In particular, chemosensory genes expressed in the peripheral sensory neurons are likely to influence insect behaviors such as preference for food, oviposition sites, and mates. Despite their key role in insect behavior and potentially speciation, the underlying genetic basis for divergence in chemosensory traits remains largely unexplored. One way to ascertain the role of chemosensory genes in speciation is to make comparisons of these genes across closely related species to detect the genetic signatures of divergence. Here, we used high throughput transcriptome analysis to compare chemosensory genes of the sister leaf beetles species Pyrrhalta maculicollis and P. aenescens , whose sexual isolation and host plant preference are mediated by divergent chemical signals. Although there was low overall divergence between transcriptome profiles, there were a number of genes that were differentially expressed between the species. Furthermore, we also detected two chemosensory genes under positive selection, one of which that was also differentially expressed between the species, suggesting a possible role for these genes in chemical-based premating reproductive isolation and host use. Combined with the available chemical and ecological work in this system, further studies of the divergent chemosensory genes presented here will provide insight into the process of chemosensory speciation among Pyrrhalta beetles. [ABSTRACT FROM AUTHOR]

Charidotella ambita offers a unique opportunity for unambiguously locating its gold reflector by comparing the structure of reflecting and non-reflecting cuticle of the elytron and pronotum. Using light microscopy and TEM, the reflector was located underneath the macrofiber endocuticle just above the epidermis. The reflector is a multilayer comprising up to 50 bilayers alternating high and low density layers parallel to the surface of the cuticle. It is chirped, i.e., showing a progressive decrease in layer thickness from approximately 150 nm–100 nm across its depth. The high density layers in contact with the endocuticle fuse to the last macrofiber when the reflector is interrupted by a trabecula, demonstrating their cuticular nature. Simulated reflectance spectra from models of the multilayer matched the reflection spectra measured on the major gold patch of the elytron of living specimens. Previous reports in adult insects exhibiting metallic colors located their reflector in the upper strata and structures of the cuticle, i.e., epicuticle, exocuticle, scales and hairs. Thus, the endocuticular location of the reflector in C. ambita (and other tortoise beetles) appears unique for adult insects. Gold reflection appears in C. ambita only when the synthesis of the macrolayer endocuticle is complete, which may take up to 2 weeks. The development of the gold reflector coincides with the start of mating behavior, possibly suggesting a signaling function in conspecific recognition once sexual maturity has been reached. [ABSTRACT FROM AUTHOR]

Understanding the mechanisms by which abiotic drivers, such as climate and pollution, influence population dynamics of animals is important for our ability to predict the population trajectories of individual species under different global change scenarios. We monitored four leaf beetle species (Coleoptera: Chrysomelidae) feeding on willows ( Salix spp.) in 13 sites along a pollution gradient in subarctic forests of north-western Russia from 1993 to 2014. During a subset of years, we also measured the impacts of natural enemies and host plant quality on the performance of one of these species, Chrysomela lapponica . Spring and fall temperatures increased by 2.5–3 °C during the 21-year observation period, while emissions of sulfur dioxide and heavy metals from the nickel–copper smelter at Monchegorsk decreased fivefold. However, contrary to predictions of increasing herbivory with climate warming, and in spite of discovered increase in host plant quality with increase in temperatures, none of the beetle species became more abundant during the past 20 years. No directional trends were observed in densities of either Phratora vitellinae or Plagiodera versicolora , whereas densities of both C. lapponica and Gonioctena pallida showed a simultaneous rapid 20-fold decline in the early 2000s, remaining at very low levels thereafter. Time series analysis and model selection indicated that these abrupt population declines were associated with decreases in aerial emissions from the smelter. Observed declines in the population densities of C. lapponica can be explained by increases in mortality from natural enemies due to the combined action of climate warming and declining pollution. This pattern suggests that at least in some tri-trophic systems, top-down factors override bottom-up effects and govern the impacts of environmental changes on insect herbivores. [ABSTRACT FROM AUTHOR]

In-field product performance assessments are an essential component of corn rootworm ( Diabrotica spp.; CRW) resistance management plans for transgenic maize ( Zea mays L.) products expressing proteins derived from the bacterium Bacillus thuringiensis (Bt). The goal of a successful field sampling program is to accurately characterize in-field product performance while also minimizing resource demand, as collection of maize root samples to evaluate CRW injury can present resource challenges such as labor intensiveness, potential safety issues, and a limited time window available for sampling. A resource-efficient sequential sampling plan was developed that utilizes data-driven root injury threshold values derived from benchmark product performance data for both single and pyramided Bt maize traits for CRW control. This sequential sampling methodology incorporates unbiased sampling and controlled false positive and false negative error rates, enabling accurate assessment decisions to be made with efficient resource use. Our proposed approach enables systematic and effective classification of in-field Bt maize product performance, with applications to other CRW control technologies besides Bt maize products. [ABSTRACT FROM AUTHOR]

• The YOLOX network was improved by introducing ECA, hard-Swish, and Focal Loss modules. • A cotton diseases and pests detection model based on improved YOLOX was developed. • The improved model was superior to other object detection algorithms. • The improved model was used to develop a cotton diseases and pests detection software based on smartphone. Cotton diseases and pests are essential factors affecting the quality and yield of cotton in agricultural production. To meet the needs of intelligent agriculture development and solve the problems of low efficiency and poor reliability of cotton diseases and pests detection, this study proposed a real-time high-performance detection model based on improved YOLOX. The model introduced Efficient Channel Attention (ECA), hard-Swish activation function, and Focal Loss function into YOLOX, which improved the ability of the model to extract image features, solved the problem of sample imbalance, improved the detection speed and accuracy, and enhanced the detection effect of cotton diseases and pests. A total of 5760 manually labeled cotton diseases and pests images (including five kinds of red leaf blight, verticillium wilt, cotton spider mite damage, double-spotted leaf beetle damage, and brown spot disease) were used to fine-tune and test the model. The mean Average Precision (mAP) of cotton diseases and pests detection reached 94.60%, the precision was 94.04%, the F1-score was 0.90, and the FPS was 74.21. Furthermore, the results were compared with five classical object detection algorithms (Faster R-CNN, SSD, YOLOv3, YOLOv4, and YOLOv5). The comparative results showed that the mAP of the improved model was 11.50%, 21.17%, 9.34%, 10.22%, and 8.33% higher than the other five algorithms, and the detection speed can meet the real-time requirements. Finally, a cotton diseases and pests detection software was designed and developed based on the improved model, deployed on the smartphone to complete the real-time detection of cotton diseases and pests in the field environment. The improved model can effectively detect the infected area of cotton leaves in the field and provide theoretical reference and technical support for controlling cotton diseases and pests. [ABSTRACT FROM AUTHOR]

Gastrophysa viridula DeGeer 1775, the green dock leaf beetle, belongs to a group of beneficial insects, which can be used as a classical biological control agent against sorrels (Rumex sp., Polygonaceae). Therefore, any infection by pathogenic organisms in this beetle is undesirable. In the present study, a new microsporidian pathogen isolated from G. viridula was identified based on morphological and ultrastructural characteristics, supported with a molecular phylogenetic analysis. Light and transmission electron microscopy studies indicated that the microsporidium was polymorphic throughout its life cycle. Sporulation stages were not all in direct contact with the host-cell cytoplasm. The fresh single diplokaryotic spores of the secondary sporulation cycle had a long narrow morphology, measuring about 5 × 2.1 µm (n = 50). Octospores produced in the secondary sporulation cycle were also observed. Morphological and ultrastructural characteristics of the life cycle stages place it within the genus Vairimorpha. The phylogenetic tree constructed on the 16S rRNA gene sequence analysis supports the morphological and ultrastructural characteristics and indicates that the pathogen is closely related to the Vairimorpha clade of microsporidia. The pathogen is named Vairimorpha gastrophysae sp. nov. [ABSTRACT FROM AUTHOR]

Females of leaf beetles and many other herbivorous insects lay eggs in coherent batches. Hatchlings emerge more or less simultaneously and often prey on their late-hatching clutchmates. It is not certain, however, whether this synchrony of hatching is a mere by-product of cannibalism or whether an additional synchronizing factor exists. The following simple experiment was aimed at determining the causal relationship between cannibalism and simultaneous larval emergence. Egg clutches of the dock leaf beetle Gastrophysa viridula were split into two halves. These halves were either kept as coherent groups in two separate dishes or, alternatively, only one half remained whole, whereas the other one was divided into single eggs, each of which was incubated in a separate dish. Halving of a clutch into coherent groups only slightly disrupted the synchrony of emergence. The consequence of individual isolation was more dramatic. Half-clutches consisting of disconnected solitary eggs required almost twice as much time for complete emergence of all larvae, which was significantly more than cannibalism as a sole synchronizing factor might explain. Moreover, survival rates were the same in coherent half-clutches (in the presence of cannibalism) and among isolated individuals. This group effect and the small contribution of cannibalism suggest the existence of an additional synchronizing factor. Possible mechanisms underpinning this phenomenon are discussed. [ABSTRACT FROM AUTHOR]

Flea beetles (Chrysomelidae, Alticinae) were collected with Pherocon AM yellow sticky traps in maize plots to compare the assemblages from transgenic Bt- (genetic event MON810, producing Cry1Ab protein effective against lepidopteran pests) and near isogenic maize in Hungary. Altogether, 51,348 flea beetle individuals from 26 species were collected. The dominant species were Phyllotreta atra (F.) and Phyllotreta vittula (Redtenbacher). Their abundances along with other (non- P. atra and non- P. vittula ) flea beetle species showed no significant differences between Bt- and isogenic maize plots. Similarly, no difference was found between Bt maize and isogenic maize plots in the species richness of the flea beetle assemblages. [ABSTRACT FROM AUTHOR]

Small ectothermic animals living at high altitude in temperate latitudes are vulnerable to lethal cold throughout the year. Here we investigated the cold tolerance of the leaf beetle Chrysomela aeneicollis living at high elevation in California’s Sierra Nevada mountains. These insects spend over half their life cycle overwintering, and may therefore be vulnerable to winter cold, and prior studies have demonstrated that survival is reduced by exposure to summertime cold. We identify overwintering microhabitat of this insect, describe cold tolerance strategies in all life stages, and use microclimate data to determine the importance of snow cover and microhabitat buffering for overwinter survival. Cold tolerance varies among life history stages and is typically correlated with microhabitat temperature: cold hardiness is lowest in chill-susceptible larvae, and highest in freeze-tolerant adults. Hemolymph osmolality is higher in quiescent (overwintering) than summer adults, primarily, but not exclusively, due to elevated hemolymph glycerol. In nature, adult beetles overwinter primarily in leaf litter and suffer high mortality if early, unseasonable cold prevents them from entering this refuge. These data suggest that cold tolerance is tightly linked to life stage. Thus, population persistence of montane insects may become problematic as climate becomes more unpredictable and climate change uncouples the phenology of cold tolerance and development from the timing of extreme cold events. [ABSTRACT FROM AUTHOR]

Chrysomela vigintipunctata (Scopoli) is a univoltine leaf beetle commonly encountered on willows across the Palearctic forest zone. The preimaginal development in this species takes place during a short time period, from May to June, because larvae are unable to consume mature leaves of the host plant. Therefore, the diet quality imposes a time constraint, and it was expected that the temperature dependence of development in C. vigintipunctata should be adaptively adjusted to the shortness and cool conditions of the favorable season. It was experimentally determined that this leaf beetle was stenothermal at the larval stage, required 275.5 degree-days above the threshold of 9.0 °C for total development from oviposition to adult emergence, and attained greater body mass at lower temperatures. However, in all of these aspects, the thermal ecology of C. vigintipunctata was similar to that of two related multivoltine species, C. populi and C. scripta . The interspecific similarity of thermal reaction norms for development rate and body size suggests that these reaction norms in C. vigintipunctata were unlikely to have been shaped by selection favoring faster development or growth early in the season. The results are discussed in terms of the “ecological fitting” concept, which states that a species may be successful in exploiting novel environments while retaining ecophysiological traits evolved elsewhere. [ABSTRACT FROM AUTHOR]

Acanthocephala is a relatively small, but distinct obligate parasitic group that includes 4 classes: Archiacanthocephala, Palaeacanthocephala, Polyacanthocephala, and Eoacanthocephala. The phylogenetic relationships of acanthocephalans are mainly based on nuclear ribosomal genes. In this study, we determined the complete mitochondrial genome sequence of Southwellina hispida (Palaeacanthocephala: Polymorphida), and used this genome sequence along with other platyzoan species (including syndermatan groups) to assess its phylogenetic position within Acanthocephala. The S. hispida mtDNA is a 14,742 bp circular molecule that contains 36 genes (lacking atp8 ) encoded in the same direction. Phylogenetic analyses of amino acid sequences for 12 protein-coding genes suggested palaeacanthocephalan species to be monophyletic, and this group to be sister to Eoacanthocephala. These results confirm other morphological and molecular data supporting palaeacanthocephalan monophyly. [ABSTRACT FROM AUTHOR]

Plant-feeding insects are spread across the entire plant kingdom. Because they chew externally on leaves, leaf beetle of the subtribe Chrysomelina sensu stricto are constantly exposed to life-threatening predators and parasitoids. To counter these pressures, the juveniles repel their enemies by displaying glandular secretions that contain defensive compounds. These repellents can be produced either de novo (iridoids) or by using plant-derived precursors. The autonomous production of iridoids pre-dates the evolution of phytochemical-based defense strategies. Both strategies include hydrolysis of the secreted non-toxic glycosides in the defensive exudates. By combining in vitro as well as in vivo experiments, we show that iridoid de novo producing as well as sequestering species rely on secreted β -glucosidases to cleave the pre-toxins. Our phylogenetic analyses support a common origin of chrysomeline β -glucosidases. The kinetic parameters of these β -glucosidases demonstrated substrate selectivity which reflects the adaptation of Chrysomelina sensu stricto to the chemistry of their hosts during the course of evolution. However, the functional studies also showed that the broad substrate selectivity allows building a chemical defense, which is dependent on the host plant, but does not lead to an “evolutionary dead end”. [ABSTRACT FROM AUTHOR]

Juvenile hormone III (JH III) plays primary roles in regulation of metamorphosis, reproduction and diapause in Leptinotarsa decemlineata , a notorious defoliator of potato. The neurosecretory cell-borne substance(s) negatively affects the final two steps in JH biosynthesis, catalyzed respectively by an epoxidase CYP15A1 and a juvenile hormone acid methyltransferase (JHAMT). In a few insect species other than L. decemlineata , the inhibitory substance is allatostatin (AS) neuropeptide. In this study, two putative AS genes encoding LdAS-C and LdAS-B precursors were cloned. Both LdAS - C and LdAS - B were expressed in the egg, larvae, pupae and adults, and highly expressed in the brain and the gut. Dietary introduction of double-stranded RNAs (dsRNAs) targeting LdAS - C and LdAS - B successfully knocked down respective target genes. Ingestion during 3 and 6 consecutive days of ds LdAS - C significantly increased the LdJHAMT mRNA levels by 3.8 and 9.9 fold respectively. In contrast, ingestion of ds LdAS - B only slightly increased the LdJHAMT expression level by 1.1 and 1.7 fold. Moreover, after one, two and three days' ingestion of ds LdAS - C , the relative JH levels in the hemolymph of treated larvae were 2.5, 4.2 and 1.9 fold higher than those in control beetles. Furthermore, ingestion of ds LdAS - C and ds LdAS - B significantly affected larval growth and delayed larval development. Thus, we provide a line of experimental evidence in L. decemlineata to support the concept that AS-C acts as an allatostatin and inhibit JH biosynthesis. [ABSTRACT FROM AUTHOR]

Chemical signals in insects have been documented to play an important role in mate recognition, and divergence in chemical signals can often cause sexual isolation between closely related species or populations within species. We investigated the role of cuticular hydrocarbons (CHCs), short distance chemical signals, in male mate recognition between the two sympatric elm leaf beetles, Pyrrhalta maculicollis and Pyrrhalta aenescens . Mating experiments demonstrated that strong sexual isolation between the two species was driven by CHCs divergence. Males preferred to mate with conspecific females with intact conspecific CHCs or conspecific CHCs reapplied after removal. Males also preferred heterospecific females that were treated with conspecific CHCs. Chemical analysis showed that the CHC profiles differ significantly between species. In P. maculicollis dimethyl-branched alkanes between C29 and C35 account for the majority of the saturated alkanes while the CHC profile of P. aenescens mostly consisted of monomethyl-branched alkanes between C22 and C29. Additionally, some compounds, such as 12,18-diMeC32, 12,18-diMeC34, are unique to P. maculicollis . [ABSTRACT FROM AUTHOR]

We review the current knowledge of the distribution, ecology, fossils, and molecular phylogeny of donaciine beetles in Japan and its adjacent regions, and discuss historical faunal change on the Japanese islands during the Quaternary. The present Japanese fauna consists of 23 species within the genera Donacia, Plateumaris, and Macroplea, nine of which are endemic to Japan. Five fossil species have been found in strata from the Late Miocene to the Middle Pleistocene; the fossil species became extinct by the Middle Pleistocene. The oldest fossils of the extant species are of two endemic species Plateumaris akiensis and P. constricticollis from the Pliocene. P. akiensis is currently confined to a single locality, whereas P. constricticollis occurs over a wide geographic range and shows marked morphological and genetic divergence. Early Pleistocene fossils of the endemic species Donacia japana and D. ozensis, and the non-endemic Donacia vulgaris have been found. Middle Pleistocene fossils of non-endemic species such as Plateumaris sericea and D. splendens have been found, suggesting their colonization of Japan during this period. Mitochondrial COI gene sequences indicate that the haplotype coalescence times date back to the Middle-Late Pleistocene in most extant species, suggesting the occurrence of colonization and/or bottleneck events during this period. Exceptionally, P. constricticollis shows a Pliocene coalescence coincident with fossil records. In addition, P. sericea likely colonized Hokkaido and Honshu/Kyushu separately during the Middle Pleistocene following the divergence of two different haplotype lineages during the Early Pleistocene. [ABSTRACT FROM AUTHOR]

The morphological integration of the hind wings of the western corn rootworm Diabrotica virgifera virgifera LeConte was investigated to get a better insight of the undergone by this invasive species. Geometric morphometric methods were used to test two modularity hypotheses associated with the wing development and function (hypothesis H1 : anterior/posterior or H2 : distal/proximal wing parts). Both hypotheses were rejected and the results showed the integrated behavior of the hind wings of D. v. virgifera . The hypothesized modules do not represent separate units of variation, so in a similar fashion as exhibited by the model species Drosophila melanogaster , the hind wings of D. v. virgifera act as a single functional unit. The moderate covariation strength found between anterior and posterior and distal and proximal parts of the hind wing of D. v. virgifera confirms its integrated behavior. We conclude that the wing shape shows internal integration, which could enable flexibility and thus enhance flight maneuverability. This study contributes to the understanding of morphological integration and modularity on a non-model organism. Additionally, these findings lay the groundwork for future flight performance and biogeographical studies on how wing shape and size vary across the endemic and expanded/invaded range in the USA and Europe infested with D. v. virgifera . [ABSTRACT FROM AUTHOR]