Journal of Economic Entomology

Bugtok disease remains a major bacterial constraint of cooking banana production in the Philippines and is characterized by vascular discoloration, fruit browning, and progressive decline associated with members of the Ralstonia solanacearum species complex that infect banana inflorescences and fruits. This study investigated whether insects visiting Saba banana flowers in Indang, Cavite harbor R. solanacearum, with emphasis on the possible role of Thrips hawaiiensis as a possible candidate vector under field conditions. Destructive sampling was conducted three times in a Saba-monoculturing farm with high reported bugtok incidence, targeting flowers present at the time of collection and prioritizing insects recovered directly from banana inflorescences. Field-collected insects were surface sterilized, subjected to bacterial isolation, and confirmed by PCR using RSSC-specific and phylotype-specific primers; representative thrips were then morphologically identified. Preliminary acquisition assay with infected flowers for 1 and 3 days was conducted using field collected T. hawaiiensis from a non-Bugtok infested farm in Laguna. Among the insects recovered, thrips and stingless bees (Tetragonula spp.) were the most prominent flower visitors, but only thrips yielded internal detection of R. solanacearum after surface sterilization and homogenization, supporting the presence of the pathogen within the insect body rather than simple external contamination. Morphological characters of the positive specimens were consistent with T. hawaiiensis, including a pale antennal segment III, bicolored body, paired pronotal posteroangular setae, discal setae on abdominal sternite VII, and a complete comb on abdominal tergite VIII. In preliminary acquisition tests, healthy T. hawaiiensis exposed to infected flowers acquired the pathogen at mean positivity values of 1.75 {+/-} 1.50 after 1 day and 2.67 {+/-} 4.72 after 3 days, whereas control thrips remained negative. These findings provide field-based evidence that T. hawaiiensis can acquire R. solanacearum from infected Saba flowers and should be considered in Bugtok epidemiology and integrated disease management in Luzon.

Objectives identified as critical for effective management of brown marmorated stink bugs, Halyomorpha halys Stal (BMSB), were addressed in the overwintering life stage. Research was conducted on a 675-acre farm in western Maryland, U.S.A. Developing and testing were done during September - October of each of the years 2013 - 2020. Traps and related materials were developed. Four invented traps plus the development and use of "weed beater" polyethylene plastic in combination with the other traps were used as attractions to BMSB during the overwintering testing periods. Overwintering BMSB showed very little interest other than to find a place to hide that was dry, dark, easy to get into and safe over the winter months (Nielson et al. 2016). Placement of traps show effect of cardinal directions due to heat and light were north = east > west = south of numbers of BMSB. These data were affected by the vegetation, type of buildings such as silos, cabins, houses, etc., around BMSB prior to the en masse flight. Silos were used as attractants from long range during the en masse flight. Five trap types were invented and tested for use against overwintering BMSB found various places such as buildings of any type, pathways in the woods and other habitats present. Trap #1 was made of plastic out of special plant pots, turned upside down with a plastic lid and entry holes top and bottom that allowed the BMSB to reach the hexcel inside and stay there. Trap #2 was made of white, rectangular coroplast and pressed into 0.5 x 0.5 x 7.32 m (5" x 5" x 24") box also holding hexcel. Traps #1 and #2 are useful for attachment to most anything with BMSB such as the eaves in houses, other buildings, vegetation, crevasses, etc. They can be placed as horizontal or vertical with other ways that enhance efficacy. Both #1 and #2 are cheap and easy to make and use. Trap #3 is made of a cardboard tube, as a fake or "faux" tree (dead and/or dying) in vegetation 20 cm (6-8") diameter and 1.22 m (3 or 4) long. The tubes are placed on tomato stakes, have hexcel and holes made as do the others and are placed vertically in the ground. The tubes are covered with small widths of white, black and or burlap around them. Lids of plastic are on top and the trap appears as a dead and/or dying tree. The fourth trap is a "mechanism" or resembling some kind of "Haven" if you will, made of "weed beater" plastic materials 1.98 m (66") wide in brown or black. The materials are placed on trees by wrapping them around 3-4 trees near 4.6 m (10-15 long). Traps 1 and 2 can then be placed on the outside of the plastic walls and the #3 fake trees can be added around the outside areas. Around 60,000 BMSB were collected and counted in these experiments by the author, and several different factors were raised and addressed to better understand the BMSB behavior during the overwintering stage. The results provide several new tools as well as understanding of approaches to address BMSB management better.

Xylosandrus crassiusculus (Motschulsky), the granulate ambrosia beetle, was one of the first highly-destructive ambrosia beetles introduced into the southern U.S in the 1970s where it was found in South Carolina (Kovach 1986). The Redbay ambrosia beetle, Xyleborus glabratus Eichhoff, was first detected in the U.S. in South Georgia in 2002. This beetle and its associated fungi, the laurel wilt fungus Raffaelea laurelensis and others have caused substantial destruction to native redbay (Persea borbonia) in GA, SC, FL and elsewhere. This beetle-pathogen complex also poses a threat to commercial avocado production in the U.S., Central and South America as well as to valuable other Persea spp. and related plants (Laureacea) that are known hosts. As an addition here, 10 years of the spring appearances (Fig.1) of X. crassiusculus in North Florida is offered for future comparisons. A second unusual appearance is the finding and working with UV mulch and ethanol, as a surprising attraction of X. crassiusculus and other ambrosia beetles including X. glabratus. It was also found that the ambrosia beetles do not respond to yellow and green as expected by most. Also, adding burlap was found to be attractive (increases dead and dying appearing trees) as is silver metallic like UV mulch, while camouflage (camo) was found to work like yellow and green. These occurrences led to the invention and development of UV mulch with new traps to better monitor ambrosia beetles. New traps led to new uses for yellow, green and camo to monitor and decrease damage and losses from ambrosia beetles. The data are presented as evaluated and appear in the figures, discussion and a supplemental section. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=139 SRC="FIGDIR/small/733798v1_fig1.gif" ALT="Figure 1"> View larger version (30K): org.highwire.dtl.DTLVardef@1006101org.highwire.dtl.DTLVardef@1e0a3d6org.highwire.dtl.DTLVardef@1244d1borg.highwire.dtl.DTLVardef@423cb7_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOFigure 1:C_FLOATNO Relative timing of annual emergence of Xylosandrus crassiusculus in north Florida. Collected over 10 years using 5 Baker traps with a 10% ethanol/water solution. Data are from years as marked. Note: data from year 2003 was not collected. C_FIG

Background: Resistance to protoporphyrinogen oxidase (PPO) inhibiting herbicides is mainly driven by diverse target-site mutations, reducing the effectiveness of this site of action in row crop systems. Fendioxypyracil is a newly developed PPO inhibitor with high intrinsic grass and broadleaf activity, but its performance against resistant populations and target-site enzyme variants remains insufficiently characterized. Results: Enzyme assays using PPO2 from Amaranthus palmeri and Setaria viridis demonstrated that fendioxypyracil maintained low IC50 values across a broad range of resistance associated mutations, including dG210 deletion and G210, R128, and G399 substitutions, whereas oxadiazon, tiafenacil, and saflufenacil showed substantial loss of potency. Greenhouse dose response experiments confirmed strong fendioxypyracil efficacy, with susceptible and G399A populations controlled at <3 g ai/ha, while dG210 and R128G populations showed only moderate shifts in sensitivity but remained effectively controlled at the recommended rate. Transgenic Arabidopsis thaliana expressing resistant PPX2 alleles exhibited faster and more severe injury with fendioxypyracil compared to saflufenacil. Field trials conducted in a PPO resistant Amaranthus palmeri population demonstrated that fendioxypyracil provided consistent weed control and density reduction, matching the performance of trifludimoxazin and saflufenacil while exceeding that of fomesafen. Conclusion: Fendioxypyracil provides robust and broad-spectrum activity against PPO resistant Amaranthus populations and target mutant enzymes, maintaining efficacy across diverse mutation backgrounds. These results demonstrate its potential as an effective tool for managing PPO inhibitor resistance and sustaining weed control in row-crop production systems.

Nutrition plays a fundamental role in insect physiology, yet whether growth, immunity and stress responses share a common nutritional optimum remains poorly understood. Using the Geometric Framework for Nutrition, we investigated how dietary protein and carbohydrate balance regulate multiple physiological functions in the specialist herbivore Plutella xylostella. Growth was jointly determined by protein and carbohydrate intake, with maximal biomass accumulation constrained primarily by protein availability. Immune traits showed distinct nutritional optima: total hemocyte counts and phenoloxidase activity were maximised at intermediate protein-carbohydrate (P:C) ratios, whereas survival following Bacillus thuringiensis challenge depended predominantly on protein intake. Antioxidant and detoxification responses likewise varied non-linearly across the nutrient landscape, with individual enzyme systems each exhibiting distinct nutrient-dependent optima. Importantly, no single macronutrient balance simultaneously maximised growth, immune performance and oxidative homeostasis, demonstrating that these functions have divergent nutritional requirements. Together, these findings show that macronutrient balance generates competing physiological demands, offering an integrated view of nutrient-dependent regulation of growth, immunity and stress physiology in a specialist herbivore.

To implement adequate nutritional landscapes to bumble bees and inform conservation efforts, we need a better understanding of how different pollen sources impact bumble reproductive performances and phenology. We assessed the impact of multiple native pollen on bees reproductive success by feeding 40 wild-caught Bombus impatiens and B. griseocollis queens with either commercially wildflower pollen mix commonly used to breed Bombus queens (control group) or 75% red maple pollen (Acer rubrum) and 25% pollen mix (RM group). In a second experiment, we monitored the reproductive success of 45 microcolonies of workers, harvested from B. impatiens colonies. Microcolonies were fed either: 1) pollen mix (N=15), 2) pollen mix and hawthorn (Crataegus canadensis, N=15), or 3) pollen mix and sumac (Rhus typhina, N=15). In experiment 1, RM significantly increased reproductive outputs for both species. RM-fed founding queens were twice more likely to produce workers, and produced them significantly earlier, though total number of workers did not vary between groups. However, RM-fed founding queens produced significantly more brood cells, males and gynes than control colonies, and produced them significantly earlier. In experiment 2, we found an interaction between initial colony diet and current microcolony diet. Overall, workers harvested from RM-fed colonies produced significantly more brood cells and males than workers harvested from control colonies. However, when fed hawthorn pollen during experiment 2, workers from control colonies performed as well as workers from RM-fed colonies. This suggests carry-over effects from early pollen sources provided to colonies on workers, which may be circumstantially offset by pollen sources with specific nutrient profile. Using detailed nutritional information of each pollen (including data on 32 nutrients), we provide nutritional requirements of pollen to support bumble bee reproduction, especially regarding vitamin B3 and vitamin C contents. This study will help inform land managers and captive breeding programs on the ideal pollen sources for bumble bees to ensure reproductively successful colonies.

Nutritional symbionts can be essential for their animal hosts. The bacterial symbiont of the leaffooted bug, Leptoglossus zonatus, Caballeronia, is acquired from the environment each generation in the 2nd instar. The symbiont is critical for L. zonatus: aposymbiotic bugs are unable to reproduce. We hypothesized that symbiotic bugs excrete Caballeronia where juveniles might find and consume them. We inoculated L. zonatus with GFP-labelled Caballeronia and examined feces of each life stage. We found that Caballeronia is excreted almost exclusively in the adult stage. We then asked if 2nd instar nymphs could acquire Caballeronia from feces. Nymphs were provided with a) feces from adults fed GFP-labelled Caballeronia, b) GFP-Caballeronia in culture, or c) water only. We found that feces-fed bugs had similar rates of symbiont acquisition to those fed Caballeronia in culture, indicating that feces can be a source of Caballeronia for L. zonatus. However, compared to culture fed individuals, bugs fed feces had reduced survivorship and required longer to develop, and surviving adults had reduced mass. Bacterial motility assays showed that in contrast to cultured Caballeronia cells, Caballeronia in feces were non-motile. These results show suggest that feces can be a source of Caballeronia, at least in some environments, however transmission mode can influence success of the offspring.

A parasitic mite of honey bee brood (Tropilaelaps mercedesae), is spreading through populations of Apis mellifera honey bees in new regions and poses a major threat to honey bee health. Despite its clear threat, the biology of this mite is poorly understood, with gaps on such fundamental issues as how fast its populations can grow. This leaves the beekeeping world underprepared to plan for its arrival and management. In this study, we documented the growth of T. mercedesae populations in untreated A. mellifera colonies in Thailand and South Korea, and did the same for another parasitic mite (Varroa destructor) when possible. We found that the population growth of T. mercedesae was variable but could reach high levels (daily r of 0.010, 0.036, and 0.057), while the population growth of V. destructor (r = 0.021) matched previous estimates. Our results indicate that T. mercedesae populations can grow rapidly but they do not always attain this potential. Based on our results, humidity should be studied as a potential driver of population growth. If future work can reveal key drivers of T. mercedesae population growth, this would help predict infestations and help design management strategies that exploit the pest's biological vulnerabilities.

In sharp contrast to biological control that seeks control of pests below economic levels, eradication programs seek total extermination of pest species. However, eradication programs are often undertaken without knowledge of the pests potential geographic distribution and relative abundance (i.e., geographic risk assessment), often leading to eradication efforts conducted across areas much greater than the potential permanent range of the target species. To demonstrate this, we review eradication efforts against the tropical New World screwworm (Cochliomyia hominivorax) in the SE USA and Mexico, the exotic sub-tropical tephritid Mediterranean fruit fly (Ceratitis capitata, medfly) in California, and the exotic tropical pink bollworm (Pectinophora gossypiella, PBW) in the SW USA. We use mechanistic physiologically based demographic models (PBDMs) that are physiologically based time varying life tables to decompose the systems and to assess risk under extant and climate change scenarios.

Frugivorous insect larvae are dependent on fruiting plants for development, leading to complex host-parasite interactions that may be influenced by many factors at various scales. We compared the relative effects of factors at the individual, neighborhood, and landscape scales in forest patches. Our results suggest that in areas like upstate New York, where agricultural land uses are dominant, individual scale factors are the most influential. Specifically, parasitism increased with host fruit crop size, but was not associated with host species richness or proximity to forest edge. Notably, the most parasitized hosts were non-native species, including Frangula alnus Mill. (Glossy Buckthorn), indicating a potential role of invasive species to shape host-parasite interactions in our system. Our results underscore the importance of host-specific traits in structuring parasitism patterns and suggest management could consider both the ecological context of host traits and the influence of invasive species at multiple scales.

The expansion of global trade has increased the risk of unintentional introductions of woodboring insects outside their native ranges, which can cause considerable ecological and economic damage. Monitoring efforts for native and non-native species of woodborers rely heavily on semiochemical-baited traps. With the goal of improving detection efforts of longhorned beetles (Coleoptera: Cerambycidae) and their associates, we conducted field bioassays in loblolly pine dominated and bottomland hardwood forest ecosystems, which are representative of subtropical Louisiana. We tested the impact of attractant composition, trap design, and the application of a friction reducing compound on the capture of longhorned beetles. We compared the Synergy Multi-Trap System with and without Fluon, and the Synergy Funnel Trap II with Fluon, baited with multicomponent cerambycid lures and ethanol or ethanol alone. In total, we collected 5,303 beetles comprising 44 species. Traps baited with cerambycid lures and ethanol captured ~11X more individuals than the traps baited with ethanol. We identified novel attractants for 6 species of longhorned beetles. When Fluon was applied, both the Synergy Multi-Trap System and Funnel Trap II were equally effective at capturing cerambycids. Application of Fluon significantly increased the trap capture of the Synergy Multi-Trap System by ~4X compared to the same trap type without Fluon. Our results contribute to our understanding of the factors influencing trap captures and the chemical ecology of woodboring insects thereby helping the development of early detection and rapid response monitoring programs in subtropical regions of the United States and elsewhere.

A growing body of literature proposes that psychoactive plant compounds evolved as defenses against herbivorous insects, with their neurological effects in humans an evolutionary accident of conserved receptor architecture. This hypothesis - which we call the herbivore defense hypothesis - is widely invoked but rarely tested empirically. We report a controlled dietary bioassay in which Spodoptera frugiperda larvae were fed artificial diet incorporating lyophilized kratom (Mitragyna speciosa) leaf powder or purified mitragynine, the primary psychoactive compound in kratom leaf. Kratom leaf caused dose-dependent larval mortality, suppressed growth rates, and reduced pupation rates across all tested concentrations, with near-complete mortality at the highest dose. Purified mitragynine produced modest but significant growth suppression relative to the control, but had no significant effect on survival and was substantially outperformed by whole leaf powder at the same mitragynine-equivalent concentration. Because insects lack the {micro}-opioid receptors through which mitragynine exerts its psychoactive effects in mammals, its insecticidal activity cannot be mediated by the same receptor interaction responsible for its human pharmacology. We use these findings to critically evaluate the herbivore defense hypothesis, and find that its current framing is insufficient to answer one of chemical ecologys most compelling questions: why do plants make compounds that alter the human mind?

The generalist Helicoverpa armigera and the specialist Helicoverpa assulta are closely related noctuid pests and are among the few insect herbivores capable of feeding on and damaging hot pepper fruits, which contain the defensive compound capsaicin. Cytochrome P450 monooxygenases (P450s) contribute to the metabolism of plant defensive compounds and can facilitate insect adaptation to chemically defended host plants. Here, we identified CYP6AN1 in H. assulta (HassCYP6AN1) and comparatively characterized the CYP6AN1 orthologs from H. armigera (HarmCYP6AN1) and H. assulta. RACE identified one full-length HarmCYP6AN1 transcript and three full-length HassCYP6AN1 transcript isoforms. The HassCYP6AN1 isoforms contained distinct 5' UTRs generated by alternative transcription initiation and splicing but shared an identical coding sequence. Sequence comparisons and phylogenetic analysis supported their assignment as orthologs. Constitutive CYP6AN1 expression was higher in the H. assulta midgut, whereas dietary capsaicin significantly induced CYP6AN1 expression in the H. armigera midgut. Recombinant CYP6AN1 proteins were co-expressed with NADPH-cytochrome P450 reductase in Escherichia coli, and their substrate-metabolizing activities were evaluated using HPLC-based depletion assays. Both orthologs metabolized capsaicin, but HarmCYP6AN1 exhibited an approximately 2.3-fold higher depletion activity than HassCYP6AN1 under the conditions tested. HarmCYP6AN1 also showed P450-content-dependent xanthotoxin depletion, whereas no detectable xanthotoxin metabolism was observed for HassCYP6AN1. These findings establish CYP6AN1 as a component of the capsaicin-metabolizing repertoire of both species and reveal substantial divergence between the orthologs in transcript organization, expression regulation, catalytic activity, and detectable substrate range.

The global expansion of Black Soldier Fly (BSF), Hermetia illucens (L.), production systems for organic waste management has increased the need to better understand its reproductive biology in order to optimize mass-rearing programs. In this study, we macroscopically characterized chronological morphological changes in the internal genitalia of adult H. illucens reared on a sustainable alternative larval diet based on coffee pulp and corn bran. Morphological assessments and dissections were conducted on female and male reproductive tracts at 3, 6, and 9 days after adult emergence. Overall, the general organization of both reproductive systems was consistent with previous descriptions. A notable observation was the presence of a tripartite fertilization chamber in females, composed of three distinct compartments apparently associated with the three spermathecae. The functional significance of this anatomical organization remains to be determined. Females showed progressively advanced ovarian development and reached the clearest morphological indicators of reproductive maturity at 9 days, while males showed the greatest testicular distention and opacity at the same age. Compared with maturation times reported in previous studies using conventional larval diets, these observations suggest a later pattern of reproductive maturation under the coffee pulp-based diet. The observed differences may be associated with the nutritional composition and carbohydrate-to-protein balance of the larval diet. These results provide chronological and iconographic information that may contribute to the optimization of laboratory rearing protocols and the use of coffee by-products in H. illucens bioconversion systems.

Pollination is of key importance for tropical agriculture, yet a bee-centred perspective often overlooks the critical role of nocturnal insects in pollination services. We evaluated the relative contributions of diurnal and nocturnal pollinators to papaya yields on subsistence farms in the Taita Hills, Kenya, a globally important biodiversity hotspot. We combined flower visitor observations with five experimental treatments: open pollination, wind-only (closed), hand pollination, and temporal exclusions for day-only and night-only services. Our results reveal complete temporal niche partitioning between diurnal bees and nocturnal hawkmoths (Sphingidae). We found that diurnal and nocturnal pollinators provide additive, rather than redundant, services, contributing to papaya fruit set and weight to a similar extent. Despite these contributions, supplementary hand-pollination experiments indicated a significant yield gap (36.9% lower fruit set), suggesting substantial pollinator limitation. While landscape-scale factors had no significant effects, nocturnal pollinators responded positively to organic management, whereas diurnal visitors did not. This indicates that local habitat quality and ecological intensification are more critical for sustaining specialised pollinators than landscape composition. Our study highlights the vital role of nocturnal insects as an ecological safety net and emphasises that their conservation through local organic practices is essential for securing yield quantity and quality in tropical papaya farming systems.

Adult mosquitoes rely on plant-derived sugars for survival, reproduction, and flight, yet the plant taxa that mosquitoes encounter in nature and the odors that make those plants attractive remain poorly understood. Most studies of mosquito attraction to plant odors have focused on candidate plants selected a priori, rather than plants linked to field-collected mosquitoes. Here, we combined plant DNA barcoding, semi-field behavioral assays, and volatile profiling to identify field-associated plant resources relevant to Aedes aegypti. Plant DNA recovered from mosquitoes collected across three Florida counties revealed broad plant associations, including 90 genera spanning 37 families, with several taxa recurring across counties or appearing prominently within particular localities. Behavioral experiments in semi-field sticky-trap assays found that five field-associated plant taxa were significantly attractive relative to blank controls, indicating that taxa associated with mosquitoes in nature can also function as attractive cues under semi-field conditions. GC-MS analyses of headspace collections from 42 plant taxa detected 211 volatile compounds and revealed substantial variation in both total emission rate and odor composition among taxa. Although several compounds, including -pinene, limonene, 4-ethylacetophenone, 2-ethyl-1-hexanol, 4-ethylbenzaldehyde, and caryophyllene, were broadly distributed across plant groups, volatile profiles differed significantly among taxa and shared compounds often occurred at markedly different proportional abundances. The five behaviorally tested taxa likewise showed both overlap and divergence, sharing 17 compounds across all five taxa while differing in dominant constituents and total emissions. Together, these results show that Ae. aegypti interacts with a diverse set of plants in the field, and suggests nectar-seeking is shaped not simply by plant identity or total odor abundance, but by the composition and proportional structure of plant odors.

IntroductionProgress against malaria has stalled since 2015, with insecticide resistance a key driver. Spatial emanators release volatile insecticides into the air, exposing mosquitoes through a route distinct from the tarsal contact used by treated nets, indoor residual spraying, and standard bioassays. Transfluthrin is currently monitored using the WHO bottle bioassay, which combines contact and vapour exposure and cannot isolate airborne effects. A scalable, vapour-only method is needed to characterise susceptibility to volatile pyrethroids. MethodsWe adapted the WHO tube bioassay to deliver non-contact transfluthrin vapour exposure without contacting treated papers. Non-blood-fed female Anopheles were exposed to acetone control or transfluthrin papers at 0.005, 0.1 and 2 mg/paper. Knockdown was recorded over 60 minutes and mortality at 24 hours. Testing spanned three laboratories (LSTM, AIRID and KEMRI) using susceptible reference and resistant lab colonies. Dose response models estimated EC{square}{square} for knockdown (EC{square}{square}KD) and mortality (EC{square}{square}Mort), with resistance ratios (RR) against the local susceptible reference. ResultsThe assay generated clear concentration- and time-dependent responses. At LSTM, Kisumu gave an EC{square}{square}KD of 0.052 and EC{square}{square}Mort of 0.054 mg/paper; Siaya was comparable (RR{square}{square}KD 1.17, RR{square}{square}Mort 0.89), whereas Tiassale 13 and KDR showed reduced susceptibility (RR{square}{square}KD 2.42 and 2.85; RR{square}{square}Mort 5.56 and 6.65). At AIRID, the resistant Cove strain did not reach 50% knockdown or mortality. At KEMRI, Siaya showed reduced susceptibility (RR{square}{square}KD 3.36/RR{square}{square}Mort 5.65). Kisumu at AIRID and KEMRI was comparable to LSTM (EC{square}{square}KD 0.007/EC{square}{square}Mort 0.030; EC{square}{square}KD 0.044/EC{square}{square}Mort 0.023). Despite inter-laboratory variation, susceptible strains remained distinguishable from resistant ones. Lower RRs than for contact pyrethroids suggest contact-based phenotypes may not predict vapour susceptibility. ConclusionThe assay provides a practical benchtop method using standard WHO hardware, distinguishing susceptible from resistant strains across three laboratories. Twenty-four-hour mortality is the recommended endpoint, 60-minute knockdown secondary. Not yet validated, it provides a foundation for further validation and adaptation to other actives.

Parasites can manipulate host behavior to increase their fitness while decreasing host fitness, a phenomenon known as an extended phenotype. Nucleopolyhedroviruses (NPVs), baculoviruses that infect Lepidopteran larvae, have been found to induce vertical climbing behavior and hyperactivity in exposed larvae. We quantified variation in the horizontal wandering behavior induced by different naturally-occurring pathogen isolates in the NPV that infects Dione (Agraulis) vanillae Linnaeus (Lepidoptera: Nymphalidae). Lab-raised larvae were infected with a constant dose of one of five different field-collected NPV isolates or a water control (n=98 larvae total), and placed in mazes to measure the horizontal distance wandered away from a food source. Virus-exposed larvae exhibited increased maximum distance of horizontal movement compared to the control, but did not significantly differ in the probability of wandering versus no movement. We also found variation in the distance wandered among the five virus isolates. However, grouping the five isolates into two previously-described viral strains or genogroups did not improve predicted differences in movement, perhaps due to the presence of within-strain genetic variation among isolates in the viral genes involved in controlling host behavior. Further work is needed to determine whether the observed between-isolate variation is the result of adaptive evolution. These results suggest that the NPV infecting D. vanillae manipulates larval behavior to increase horizontal wandering, which could lead to higher pathogen fitness by increasing long-distance dispersal of the virus across the landscape.

Plant-parasitic nematodes (PPNs) are among the most destructive agricultural pests worldwide, causing significant economic losses across diverse cropping systems. Soil fumigation, the most common management strategy, is costly, detrimental to soil health, and increasingly restricted due to environmental and regulatory concerns. As a result, there is a critical need for alternative, sustainable approaches for PPN control. Solanum sisymbriifolium is resistant to several Meloidogyne species and represents a promising source of natural nematicidal compounds. In this study, we evaluated the effects of S. sisymbriifolium extracts on Meloidogyne chitwoodi and M. hapla, two economically important nematodes. Compounds were extracted using solvents of increasing polarity and then reconstituted in water. The water-solubilized extracts were then used in bioassays to assess their effects on nematode egg hatching, egg viability, and second-stage juvenile (J2) survival. Egg hatching and J2 viability of both Meloidogyne species were consistently affected by compounds in the 1-butanol fraction. Further characterization of these compounds may enable the development of novel, environmentally sustainable alternatives to conventional nematode management strategies.

O_LIFloral nectar plays a critical role in shaping the ecology and evolution of plant-pollinator interactions. Effective and efficient methods that allow for broad-scale sampling of nectar volume and sugar concentration across a diversity of taxa are needed to improve our understanding of many dimensions of mutualistic plant-pollinator interactions--including their basic ecology and evolution, their responses to environmental change, and their conservation and restoration. C_LIO_LIDespite the key importance of nectar for mediating plant-pollinator interactions, quantifying floral nectar in the field from many different plant species is challenging because there is often no one-size-fits-all sampling method that is effective across a diversity of floral structures and nectar traits. Different methods require different preparation, and sampling from many species involves a variety of logistical challenges. C_LIO_LIHere we provide a methodological roadmap for sampling floral nectar in the field from many different plant species. We describe our nectar collection methods in detail, including necessary equipment, calculations, and approaches appropriate for different floral morphologies. We also provide a troubleshooting guide for common problems encountered while collecting nectar in the field. To demonstrate the utility and effectiveness of our methods for collecting nectar from many different species, we present results on nectar trait variation from 53 species in an ecosystem. C_LIO_LIOur method illustrates that nectar traits vary considerably within and among plant species, indicating that large-scale nectar sampling projects are an important consideration for many basic and applied questions in pollination ecology and evolution. We hope that across many plant communities and ecosystems, our paper provides a practical roadmap for how to navigate the complexities of quantifying floral nectar traits. C_LI