The Special Collection ‘Spodoptera frugiperda (fall armyworm): Ecology and Management of its World-scale Invasion Outside of the Americas’ presents reviews and research that address topics of overarching interest and contributes to a better understanding of this pest and its management, now that it has spread outside the Americas. The collection is a combination of invited articles presenting new information published for the first time, invited review papers, and a selection of relevant high-quality articles previously published in Journal of Economic Entomology (JEE). Articles in the Collection, as well as selected citations of articles in other publications, reflect the increase in research on S. frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), which became the most important pest of maize in the world during recent years. This Special Collection addresses a wide range of topics, including pest behavior, host strains, insecticide and Bt protein resistance, biological control, host plant resistance, and yield loss estimates. Topics are presented in context of research primarily conducted in regions outside of the Americas where S. frugiperda has invaded and disrupted crop production to varying degrees. In recognition of further spread, the threat of a S. frugiperda invasion into Europe and potential management options are also presented.

Fall armyworm (Spodoptera frugiperda [J.E. Smith]) is a moth native to the Western Hemisphere where it is a major pest of corn (maize) and multiple other crops. It is now a global threat with its recent discovery and dissemination in the Eastern Hemisphere. Its broad host range is in part due to two subpopulations denoted as ‘host strains’ that differ in host plant specificity. Therefore, identifying the strains present in a location is critical to assessing what crops are at risk of infestation. However, much remains uncertain about how the strains differ and even on the fundamental issue of how they are identified. Complicating factors include the host strains are morphologically indistinguishable, the defining behavior of the strains (host plant specificity) is variable, and the existence of significant differences between geographical populations and laboratory colonies that are independent of strain identity. These factors contribute to substantial disagreements in the literature on presumptive strain differences. This paper presents a summary of strain characteristics and suggests the criteria that should be met before concluding a trait is ‘strain-specific’. The intent is to facilitate a common understanding of what the strains represent and to develop a more consistent experimental framework for studies on strain phenotypes. Evidence is summarized that supports a primary role for Z-linked genes in strain identity, which has potential implications for genetic approaches to define the strains, and we discuss the possibility that the strains arose from allopatric (rather than sympatric) speciation processes.

When an invasive species first breaches quarantine and establishes in yet another country, it invariably causes consternation for growers, in part because of incomplete understanding of the plants that are at risk. The Fall Armyworm, Spodoptera frugiperda (J.E. Smith) is the most recent example in Australia. The number of plants that this polyphagous noctuid is reported to attack is vast, including many crop species. Consequently, initial reactions from grower industry groups that perceived themselves at risk were to demand emergency use of insecticides. Yet the field evidence suggests that many crops might not be at risk and since S. frugiperda arrived in Australia, maize crops have suffered most damage, followed by sorghum. We question the accuracy of some of the claims of reported host plants of S. frugiperda and report experiments that compared oviposition behavior, neonate silking behavior, and larval performance on five crops: the known hosts maize and sorghum, and the putative hosts cotton, peanut, and pigeon pea. Maize ranked highest in all preference and performance measures, followed by sorghum and peanut, with pigeon pea and cotton ranking lowest. Although S. frugiperda can survive, develop, and pupate on the crop species we examined, cotton and pigeon pea are not preferred by the pest in either the larval or adult stages. We suggest that before a plant is listed as a host for a given insect that the evidence should be fully reported and carefully evaluated. Collecting an immature insect from a plant does not make that plant a host!

The fall armyworm, Spodoptera frugiperda, is an economically important pest of corn, cotton, and soybean, and a major target of transgenic crops expressing Bacillus thuringiensis (Bt) proteins. In recent years, this insect has invaded most countries in Africa, Southeastern Asia, and Oceania, posing a great threat to food security. Successful use of Bt crops in the U.S. indicates that Bt technology can be an effective tool for management of S. frugiperda in other countries. Evolution of insect resistance is the primary threat to the long-term efficacy of Bt technology. There are many factors that may affect the rate of evolution of insect resistance to Bt crops, which include initial resistance allele frequency, the dose of Bt protein in Bt crops, cross-resistance, complete/incomplete resistance, and fitness costs associated with resistance. Currently, the high dose/refuge and gene-pyramiding approaches are the two main IRM strategies used in the U.S. to combat evolution of insect resistance. In this paper, we review research on resistance of S. frugiperda to Cry1, Cry2, and Vip3Aa proteins. Specifically, we discuss the resistance allele frequencies of S. frugiperda to these three proteins in the field, the genetic basis of resistance, the patterns of cross-resistance, and the fitness costs associated with resistance. Experience and knowledge gained from these studies provide valuable information for the successful use of Bt crop technology for control of S. frugiperda worldwide.

Insecticides and genetically modified Bt crops are the main tools for control of the fall armyworm, Spodoptera frugiperda (J.E. Smith). Since its invasion of Africa, the Far East, and Australia where Bt crops are largely absent, insecticide use has increased and reduced susceptibility to several insecticides used for decades in its native distribution area have been reported. Poor efficacy at field-level is sometimes incorrectly ascribed to pest resistance, while numerous other factors influence efficacy at field-level. In this paper, we review the history of insecticide resistance in S. frugiperda and discuss the influence that life history traits, migration ecology, and chemical control practices may have on control efficacy and resistance evolution. The indirect role that poor national policies have on pesticide use practices, and indirectly on control efficacy and selection pressure is discussed. Evidence shows that local selection for resistance drives resistance evolution. Integrated pest management, rather than reliance on a single tactic, is the best way to suppress S. frugiperda numbers and the over-use of insecticides which selects for resistance.

We here review and discuss management options that growers in Europe could take in response to the expected invasion of the fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae). The focus is put on maize but the information provided is also relevant for other crops potentially affected. A sound forecasting system for fall armyworm both on a regional as well as at local scale should be established to alert growers as early as possible. Whilst a number of cultural control methods are adopted by maize growers in different regions globally to fight fall armyworm, many of them may either not be highly effective, too laborious, or otherwise unfeasible within the mechanized crop production systems used in Europe. Potential is seen in the stimulation of natural enemies through conservation biocontrol approaches, e.g., the planting of flower strips or intermediate cover crops, reducing tillage intensity, and avoiding broad-spectrum insecticides. To manage fall armyworm infestations, several effective biologically-based products are available globally, and some in Europe, e.g., based on specific baculoviruses, certain Bacillus thuringiensis strains, few entomopathogenic nematodes, and a number of botanicals. These should be given priority to avoid a major influx of insecticides into the maize agro-ecosystem once the fall armyworm arrives and in case growers are not prepared. Plant protection companies, particularly biocontrol companies should act proactively in starting registration of ingredients and products against fall armyworm in Europe. European maize growers should be made aware, in time, of key features of this new invasive pest and appropriate control options.

Fall armyworm (Spodoptera frugiperda Smith), a serious pest of cereals from the Americas, has spread across sub-Saharan Africa and Asia since 2016, threatening the food security and incomes of millions of smallholder farmers. To measure the impact of S. frugiperda under different management approaches, we established on-farm trials across 12 landscapes (615–1,379 mm mean annual rainfall) in Malawi and Zambia during the 2019/2020 and 2020/2021 seasons. Here we present the results from our conventional tillage, monocrop maize, no pesticide treatment, which served to monitor the background S. frugiperda impact in the absence of control measures. Median plot-level S. frugiperda incidence ranged between 0.00 and 0.52 across landscapes. Considering severe leaf damage (Davis score ≥5), the proportion of affected plants varied between 0.00 and 0.30 at the plot scale, but only 3% of plots had ≥10% severely damaged plants. While incidence and damage severity varied substantially among sites and seasons, our models indicate that they were lower in high tree cover landscapes, in the late season scouting, and in the 2020/2021 season. Yield could not be predicted from S. frugiperda incidence or leaf damage. Our results suggest S. frugiperda impacts may have been overestimated at many sites across sub-Saharan Africa. S. frugiperda incidence and damage declined through the cropping season, indicating that natural mortality factors were limiting populations, and none of our plots were heavily impacted. Long-term S. frugiperda management should be based on Integrated Pest Management (IPM) principles, including minimising the use of chemical pesticides to protect natural enemies.

The fall armyworm (FAW) Spodoptera frugiperda (Smith; Lepidoptera: Noctuidae) is present in over 70 countries in Africa, Asia, and Oceania. Its rapid dispersal since 2016 when it was first reported in western Africa, and associated devastation to agricultural productivity, highlight the challenges posed by this pest. Currently, its management largely relies on insecticide sprays and transgenic Bacillus thuringiensis toxins, therefore understanding their responses to these agents and characteristics of any resistance genes enables adaptive strategies. In Australia, S. frugiperda was reported at the end of January 2020 in northern Queensland and by March 2020, also in northern Western Australia. As an urgent first response we undertook bioassays on two Australian populations, one each from these initial points of establishment. To assist with preliminary sensitivity assessment, two endemic noctuid pest species, Helicoverpa armigera (Hübner; Lepidoptera, Noctuidae) and Spodoptera litura (Fabricius; Lepidoptera, Noctuidae), were concurrently screened to obtain larval LC50 estimates against various insecticides. We characterized known resistance alleles from the VGSC, ACE-1, RyR, and ABCC2 genes to compare with published allele frequencies and bioassay responses from native and invasive S. frugiperda populations. An approximately 10× LC50 difference for indoxacarb was detected between Australian populations, which was approximately 28× higher than that reported from an Indian population. Characterization of ACE-1 and VGSC alleles provided further evidence of multiple introductions in Asia, and multiple pathways involving genetically distinct individuals in Australia. The preliminary bioassay results and resistance allele patterns from invasive S. frugiperda populations suggest multiple introductions have contributed to the pest's spread and challenge the axiom of its rapid ‘west-to-east’ spread.

Control of fall armyworm (FAW) Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) since its invasion of Africa still depends on pesticides. Early detection of adults is considered the key to the success of larvae control in the crop field. However, FAW control thresholds based on current monitoring techniques are not well established in Africa. We investigated the efficacy of moth capture frequencies and FAW incidence levels as decision tools for FAW management. Experiments were conducted over two maize cropping seasons during which FAW incidence, severity, and larvae count were recorded during destructive sampling after the application of a homologated insecticide. During the first season, the FAW incidence ranged from 37.5 ± 5.6% in the 25% incidence threshold treatment to 48.1 ± 8.1% in the control. During the second season, the incidence was significantly lower in the 25% incidence threshold treatment (55.8 ± 5.7%) compared with the control (75.7 ± 3.0%). Over the two seasons, no significant difference in FAW damage severity was recorded between the treatments and control. The highest number of larvae per plant (4.0 ± 0.6) was observed in the 10% incidence threshold treatment. Insecticide application did not consistently contribute to reducing FAW incidence and observed plant damage did not translate into yield loss. FAW control needs further investigation to establish a threshold above which damage translates into yield loss, thus necessitating control intervention.

Direct and indirect injury caused by Dalbulus maidis (Hemiptera: Cicadellidae) in corn is an ever-increasing concern in Brazil and other corn-producing countries of the Americas. This highly efficient vector transmits corn stunting pathogens and is of economic concern in the Neotropics, including temperate regions where epidemic outbreaks are now common. Despite the progress made so far, Brazilian corn growers continue to struggle with this pest and its associated pathosystem. In this review, we gathered relevant and updated information on the bioecology, population dynamics, and damaging potential of D. maidis. Our goal was to better understand its intimate association and complex interactions with the host crop and transmitted pathogens. Based on available scientific literature, we identified factors which explain the recent increase in D. maidis occurrence in South America, including the cultivation of corn during multiple growing seasons, overlapping of susceptible crops, and widespread use of genetically modified hybrids. The reasons for the overall inefficiency of current suppression strategies aimed at this pest are also summarized. Finally, a management program for D. maidis and corn stunt disease is proposed, combining strategies such as eradicating volunteer corn, reducing the planting period, using tolerant hybrids, and applying chemical and/or fungal insecticides. Prospects regarding the pest's status are also outlined. Overall, the information presented here will serve as a decision-making guide within Brazilian and South American corn production systems, as well as paving the way for devising novel strategies aimed at suppressing D. maidis populations and limiting the spread of corn stunt disease.

Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) (fall armyworm) is an extremely destructive insect pest that causes crop losses, especially cereal production across the world. Its management is challenged by its high migratory ability, polyphagous nature, high fecundity level, and short life cycle. It has become a serious threat across the globe that requires proactive and coordinated regional and global interventions. Although synthetic insecticides have been widely utilized to control the pest, there are numerous inherent challenges associated with the overreliance and overuse of these chemicals, e.g., toxicity to humans, destruction of natural pest enemies and pollinators, environmental and food contamination, pest resurgence, secondary pest outbreaks, and resistance development. Plant-derived pesticides such as Azadirachta indica, Eucalyptus globulus, Jatropha curcas, Lantana camara, Phytolacca dodecandra, and Piper guineense have been evaluated under laboratory, greenhouse, and field conditions to control S. frugiperda. We are certain that the substantial potential of these plants under field conditions could be enhanced and promoted together with existing plant-based products (registered) for use against S. frugiperda as an alternative in integrated pest management schemes. Therefore, this review highlights challenges and prospects that will help refocus and increase research attention on the development and application of botanical pesticides under field conditions rather than only under laboratory and control conditions to increase the commercialization and adoption rate of this technology across the globe.

Large-scale soybean [Glycine max (L.) Merr.] cultivation has substantially transformed the Midwestern landscape in recent decades. Floral nectar produced by immense fields of soybeans has the potential to influence foraging ecology and resource accumulation of honey bee (Apis mellifera L.) colonies. In this study, we combined microscopic and molecular pollen analysis of honey samples with waggle dance inference of spatial foraging patterns to demonstrate that honey bees routinely forage on soybeans in Ohio. In analyzing honey samples from across the state, we found ubiquitous presence of soybean pollen in honey collected from agricultural lands during soybean bloom. The abundance of soybean pollen in honey increased with the amount of soybean fields surrounding the apiaries. Honey bee waggle dances recorded during soybean bloom revealed that honey bees preferred soybean fields for foraging over other habitat types. With these results, future research efforts aimed at enhancing mutual interactions between soybeans and honey bees may represent an unexplored pathway for increasing soybean production while supporting honey bees and other pollinators in the surrounding landscape.

The sharpshooter Cicadella viridis L. (Hemiptera: Cicadellidae) is the most common sharpshooter in Europe and, given its xylem feeding behavior, is considered a potential vector of the plant pathogenic bacterium Xylella fastidiosa Wells et al. (Xanthomonadales: Xanthomonadaceae). We tested X. fastidiosa subsp. pauca ST53 (Xfp) transmission capabilities of C. viridis adults, namely 1) acquisition efficiency from four host plant species—periwinkle, milkwort, lavender, alfalfa—and from two artificial diets (PD3 and Xfm), 2) inoculation efficiency to periwinkle at different times post acquisition from different plant and artificial diet sources. The main European vector species—Philaenus spumarius L. (Hemiptera: Aphrophoridae)—was used as a control. C. viridis was able to acquire Xfp from periwinkle, milkwort, and lavender, although with low efficiency (3–16%) and from artificial diets (23–25%). Successful inoculation on periwinkle was extremely rare, being observed only three times, following feeding on milkwort plant and PD3 artificial diet sources. Our study shows that C. viridis is not a relevant vector of Xfp, given the very low transmission rate in controlled conditions, and the inability to feed on olive. The low efficiency reported here correlates with ecological constraints of the vector (mainly monocots host plants, humid environments) that make it difficult to forecast a relevant role in dispersing X. fastidiosa, at least within the present distribution of the exotic bacterium in Europe. However, a possible role of this species in spreading Xf in other agroecosystems, e.g., vineyard and stone fruits grown in humid areas, cannot be excluded.

Antheraea pernyi Guérin-Méneville (Lepidoptera: Saturniidae) is of high economic value as a source of silk, food, and bioactive substances with medicinal properties. A. pernyi larvae are prone to A. pernyi vomit disease (AVD), which results in substantial economic losses during cultivation; however, the relationship between AVD and A. pernyi gut microbiota remains unclear. Here, we investigated the bacterial community in the midgut and feces of A. pernyi larvae with and without AVD using 16S rRNA gene sequencing with Illumina MiSeq technology. Compared with healthy larvae, intestinal bacterial diversity and community richness increased and decreased in larvae with mild and severe AVD, respectively. In addition, the proportion of gut Enterobacter Hormaeche and Edwards(Enterobacteriales: Enterobacteriaceae) and EnterococcusThiercelin and Jouhaud (Lactobacillales: Enterococcaceae) was higher and lower, respectively, in larvae with mild AVD than those in healthy larvae. A. pernyi vomit disease infection significantly increased the genera with abundance <1%. In the gut of larvae with severe AVD, the proportion of Turicibacter Bosshard et al. (Erysipelotrichales: Turicibacteraceae) increased significantly to 81.53–99.92%, whereas that of Enterobacter decreased compared with healthy larvae. However, the diversity of fecal bacteria was similar between healthy larvae and those with mild AVD. Overall, the findings demonstrate that intestinal microflora in A. pernyi larvae are altered by AVD infection and may cause secondary bacterial infection. This is the first report of the presence of Turicibacter in the intestinal tract of lepidopterans.

Orius sauteri (Poppius) is an important predator of many economically important insect pests. The mass rearing of O. sauteri is difficult, limiting its application in pest control. Here we assessed the nutritional quality of eggs of Sitotroga cerealella (Olivier), Agrotis ypsilon (Rottemberg), or Spodoptera litura (Fabricius), and their potential for rearing O. sauteri in the laboratory for two generations. Of species tested, S. cerealella eggs resulted in the highest survival and reproduction of O. sauteri compared to the other two lepidopteran species. Eggs of A. ypsilon were a suitable diet for the nymphal stage, which developed faster on A. ysilon eggs than those of S. cerealella eggs. Conversely, eggs of S. litura were not a suitable diet for O. sauteri, and they disrupted the development and reproduction of O. sauteri. Sitotroga cerealella eggs showed advantages in all the nutritional components evaluated. Orius sauteri fed S. litura eggs contained significantly lower protein levels than those fed on the other eggs tested. Spodoptera litura eggs significantly enhanced the CAT activity in O. sauteri, which suggests that some components from S. litura eggs harmed the development and reproduction of O. sauteri. Based on these results, we suggest using a combined diet for mass rearing of the pirate bug, feeding the nymphs and adults with A. ypsilon eggs and S. cerealella eggs, respectively. This study contributes to the discovery of artificial diets for mass rearing O. sauteri and other Orius species in the future.

The browntail moth (Euproctis chrysorrhoea L.) is an invasive species which over the past five years, has been undergoing outbreaks on a scale not seen in the northeastern U.S. in over 100 years. Browntail moth larvae feed on and defoliate a number of deciduous tree species, but the health issues caused by contact with the toxic urticating hairs of the overwintered larvae have resulted in very low tolerance for this pest amongst homeowners and land managers. Few recent studies have been conducted to assess management options for browntail moth, which is abundant in ecologically sensitive areas along coastal waters, and around people's homes. We investigated the potential to manage overwintered larvae with currently available biorational insecticides. Laboratory bioassays revealed susceptibility to Beauveria bassiana (Balsamo) Vuillemin (Hypocreales: Cordycipitaceae), Bacillus thuringiesis kurstaki (Berliner), azadirachtin, and spinosad products. A field trial was conducted to assess efficacy of B. bassiana, Btk, and azadirachtin. All treatments reduced the abundance of larvae compared with the control, but only two applications of Btk and single application of a tank mix of B. bassiana and Btk reduced pupal nest abundance. A laboratory experiment revealed that temperature did not affect the feeding and survival of larvae exposed to the field trial foliage from the Btk and the Btk/B. bassiana tank mix treatments, whereas slower feeding rates and increased time to death were observed with the control and B. bassiana alone treatment.

The parasitoid Psyllaephagus bliteus Riek (Hymenoptera: Encyrtidae), entomopathogenic fungi, and chemical insecticides are the main strategies to manage the eucalypts pest Glycaspis brimblecombei Moore. The objective of this study was to isolate and to identify entomopathogenic fungi, collected from Bemisia tabaci Gennadius adults in soybean and tomato crops, and from soil samples in eucalypts, soybean, and native forest areas to evaluate their potential to manage G. brimblecombei. Twelve Beauveria and Cordyceps isolates were selected and compared with the commercial products Boveril Beauveria bassiana Bals. (Hypocreales: Cordycipitaceae), Metarril Metarhizium anisopliae Metschn. (Hypocreales: Clavicipitaceae), and Octane Cordyceps fumosorosea Wize (Hypocreales: Cordycipitaceae) and their respective strains. The fungal isolates were diluted in 0.1% aqueousTween 80 at a concentration of 1.0 × 10⁸ conidia/ml and sprayed on the G. brimblecombei nymphs with or without lerps. Pest mortality was higher and the TL₅₀ and TL₉₀ lower with the isolates LCBPF 11 C. javanica Frieder. & Bally (Hypocreales: Cordycipitaceae), LCBPF 12 (C. fumosorosea), and LCBPF 67 (C. fumosorosea) from B. tabaci adults. Fungi of the genera Beauveria and Cordyceps developed and caused high mortality of G. brimblecombei nymphs with lerps. The B. bassiana, C. cateniannulata Liang (Hypocreales: Cordycipitaceae), C. fumosorosea, C. javanica, and M. anisopliae isolates showed potential to manage G. brimblecombei. The lerp of this insect enhances entomopathogenic fungus development as a source of inoculum accelerating G. brimblecombei nymph mortality. Entomopathogenic fungi isolated from insects and soils are effective against G. brimblecombei and the presence of the lerp of this insect increases the effectiveness of its control.

Avocados are generally poor hosts or nonhosts for tephritid fruit flies, which can influence the type of mitigation measures required by export protocols for trade. We conducted experiments to determine the susceptibility of the avocado, Persea americana, cv. ‘Malama’ to infestation by Oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera:Tephritidae), in Hawai’i using laboratory and field no-choice cage tests, together with field sampling. In no-choice cage tests, infestation rates increased with decreasing fruit firmness over time after harvest. Although risk of infestation was negatively correlated with fruit firmness, about 50% of mature hard fruit exposed immediately after harvest became infested. In field cage tests, mature hard fruit on the tree at the 25% purple color stage were not infested, whereas fruit at the 50, 75, and 100% purple color stages were infested at relatively low rates. Field sampling of fallen ‘Malama’ fruit over two seasons showed no natural infestation by B. dorsalis and trap captures in avocado orchards using McPhail traps containing protein bait lures averaged 0.13 ± 0.03 (mean ± SE) flies per trap per week, underscoring the low prevalence of fruit flies in avocado orchards and the poor host quality of this cultivar. A systems approach based on poor host status, low prevalence, and a limited harvest period (October to March) and distribution area (northern tier states) is proposed to export ‘Malama’ avocados from Hawai’i to the continental United States.

The Euwallacea fornicatus species complex (Coleoptera: Curculionidae: Scolytinae: Xyleborini) is a group of four cryptic ambrosia beetle species. Native to Asia, several members of the complex have invaded other continents, where they cause significant economic losses to agricultural crops (e.g., avocado) and natural ecosystems. We were primarily interested in developing management strategies by focusing on the flight behavior of the beetles. Thus, seasonal differences in flight activity were assessed using panel traps baited with a commercial quercivorol lure, placed in infested avocado orchards in Danei, Tainan, Taiwan. Same traps were used to investigate the flight activity of a natural enemy, an undescribed species of the Braconid genus Eucosmophorus sp. Shothole borer species were identified using a DNA-based, high resolution melting assay. Trap data were compared to the predictions of a simple degree-day model, incorporating developmental data and several environmental parameters known to influence flight. Such as the time period representing most of flight activity in a day and temperature-dependent flight propensity. In stark contrast to the degree-day model which predicted the highest emergence, and by extension flight, of shothole borers during spring and summer (May to November), flight activity was actually lowest during these months, and instead, peaked during the winter (October to March). Abundance of the parasitoid wasp closely mirrored flight activity of the shothole borers. The mismatch of trapping and modeling data can have many causes, heavy precipitation and possibly cooperative brood care may suppress the dispersal behavior of the shothole borers during the summer.

Methyl benzoate (MBe), a volatile organic molecule, has been shown to have insecticidal effects on a variety of agricultural, stored products, and urban arthropod pests in recent investigations. However, the toxicity of MBe against nontarget organisms has rarely been investigated. This study investigated the lethal and sublethal effects of MBe on the generalist predator Orius laevigatus (Fieber) (Hemiptera: Anthocoridae) via different exposure routes. This species is an important natural enemy of thrips, aphids, and mites in biological control programs globally. Acute toxicity bioassays conducted on O. laevigatus showed that the lethal median concentration (LC₅₀) values of MBe for topical and residual toxicity were 0.73 and 0.94%, respectively, after 24 hr of exposure. Importantly, a sublethal concentration of MBe (LC₃₀ = 0.51%) did not affect the survival and reproduction of O. laevigatus. In addition, prey consumption by O. laevigatus under different exposure conditions with varying densities of Aphis gossypii (Glover) (Hemiptera: Aphididae) adults demonstrated a good fit for a Type II functional response. The sublethal concentration of MBe did not affect the attack rate and handling time of O. laevigatus compared to untreated insects, nor did it affect the longevity and fecundity of O. laevigatus females. Thus, according to the International Organization for Biological Control, the sublethal MBe concentration for O. laevigatus is categorized as harmless and may be used in conjunction with this predator species for integrated control of many agricultural insect pests.

Graphical Abstract

The acaricidal activities of 86 plant extracts were investigated under laboratory conditions. The ethanol extract of Dioscorea japonica Thunb. root showed the strongest acaricidal activity, with 89.3% mortality against two-spotted spider mite, Tetranychus urticae Koch adults at a 2 mg/ml concentration. Bioassay-guided isolation of D. japonica root extract using silica gel open column chromatography, gas chromatography (GC), and gas chromatography–mass spectrometry (GC–MS) identified palmitic acid as the primary active compound. The acaricidal activities of palmitic acid against T. urticae were 91.2% and 69.7% at concentrations of 1 and 0.5 mg/ml, respectively. Among nine saturated fatty acids with carbon chains ranging from C₈ to C_26, the most vigorous acaricidal activity was observed with octanoic acid, followed by palmitic acid, and decanoic acid at a 1 mg/ml concentration. The acaricidal activity of the other fatty acids was less than 40% mortality at a 1 mg/ml concentration. These results indicate that a suitable carbon length is essential for fatty acids to exhibit acaricidal activity. The acaricidal efficacy of Eungjinssag (EJSG), an organic agricultural material authorized for the management of mites in the Republic of Korea, was compared to D. japonica root extract. At concentrations above 1 mg/ml, the acaricidal activity of D. japonica root extract was stronger than that of EJSG. The results of this study show that D. japonica root extract and palmitic acid are promising candidates as new environmentally-friendly control agents against two-spotted spider mite, which is one of the most severely damaging agricultural arthropod pests.

Wireworms are primary pests of potatoes in Canada. Presently, the highly toxic organophosphate phorate (i.e., Thimet 20G) is the only effective insecticide in use in Canada. As such, there is an urgent need for novel alternative treatments that provide competitive tuber blemish protection and wireworm reduction with a safer human and environmental portfolio. Herein we evaluated broflanilide, a novel meta-diamide insecticide for both tuber protection and wireworm mortality. When evaluated in field trials in Agassiz, British Columbia over 6 yr, broflanilide applied as a seed piece treatment (SPT) to mother tubers at 1.5–2.0 g AI/100 kg seed (approx. 50 g AI/ha), or as an in-furrow spray (IFS) at 0.23–0.25 g AI/100 m row (approx. 25 g AI/ha) was as effective at reducing blemishes to daughter tubers by wireworms (Agriotes obscurus) as phorate (Thimet 20G at 3230 g AI/ha), bifenthrin (Capture 2EC IFS at 300 g AI/ha) and clothianidin (Titan ST at 312.5 g AI/ha). In addition, broflanilide SPT and IFS applied at the above rates reduced resident wireworms (in the field at the time of planting) by 95.4–99.0% and neonate wireworms (produced from eggs laid during the growing season) by 98.1–100%. Similar results were obtained when broflanilide IFS (nonsystemic) was paired with clothianidin SPT (systemic) for broad-spectrum potato insect pest control. Strategies for the use of broflanilide on wheat (e.g., Teraxxa F4) in rotation with potatoes (Cimegra), both registered in Canada in 2020 are discussed.

Hemp (Cannabis sativa L.) is a reemerging crop in the United States with increasing outdoor acreage in many states. This crop offers a potential host for polyphagous, defoliating lepidopteran pests currently present in Louisiana. The ability of soybean looper [Chrysodeixis includens (Walker)] (Lepidoptera: Noctuidae), fall armyworm [Spodoptera frugiperda (J.E. Smith)] (Lepidoptera: Noctuidae), and beet armyworm [Spodoptera exigua (Hübner)] to develop and reproduce on hemp was investigated in this study. Insects were reared on two hemp varieties, Maverick and Pipeline, as well as documented host plants soybean [Glycine max (L.) Merr.] (Fabales: Fabaceae) variety UA5414RR and cowpea [Vigna unguiculata (L.)] (Fabales: Fabaceae) variety Quickpick Pinkeye. Larvae of all three species reared on ‘Maverick’ had significantly faster preadult developmental times compared to the other hosts. Chrysodeixis includens larvae fed excised leaves of ‘Maverick' and ‘Pipeline’ experienced higher intrinsic and finite rates of increase, higher net reproductive rates, and faster mean generation and doubling times. Spodoptera frugiperda larvae reared on ‘Maverick’, ‘Pipeline’, and ‘UA5414RR’ had higher intrinsic and finite rates of increase, higher net reproductive rates, and faster mean generation and doubling times compared to ‘Quickpick Pinkeye’. Spodoptera exigua larvae had the highest survivorship on ‘Maverick’ and similar, positive lifetable statistics when reared on ‘Maverick’ and ‘Pipeline’. The results of this study indicate hemp is an alternative host plant that has the potential to influence the population dynamics of C. includens, S. frugiperda, and S. exigua in Louisiana agroecosystems they co-occur in.

To determine the factors leading to outbreaks of the sugarcane aphid, Melanaphis sacchari, (Zehntner) (Hemiptera: Aphididae) in sorghum in Haiti, a survey was carried out on farms during two cropping seasons, spring and fall of 2018. A total of 45 plots in three Haitian regions were monitored from the five-leaf stage to grain ripening. Infestation with M. sacchari was significantly higher in spring than in fall, except in one location. Melanaphis sacchari populations varied significantly according to phenological stages of sorghum, with significantly higher abundance during the heading and flowering stages than other stages. In and around sorghum fields, the sugarcane aphid was observed on plants from three families: Poaceae, Malvaceae, and Cucurbitaceae. Aphid natural enemies found in sorghum fields consisted of eight species of ladybeetles (Coleoptera: Coccinellidae), one hoverfly (Diptera: Syrphidae), one lacewing (Neuroptera: Chrysopidae), and one predatory midge (Diptera: Cecidomyiidae). In addition to these predators, two parasitoid species, Adialytus sp. (Hymenoptera: Braconidae) and Pachyneuron aphidis (Bouché) (Hymenoptera: Pteromalidae), emerged from sugarcane aphid mummies. Predator and parasitoid densities were highly affected by growing season, with most of the biological control happening in fall. This study provides insights on sugarcane aphid management in Haiti and the Caribbean Islands.

L'objectif de cette étude est de déterminer les facteurs pouvant conduire à une infestation des champs de sorgho en Haïti par le puceron de la canne à sucre Melanaphis sacchari, (Zehntner) (Hemiptera: Aphididae). L'étude a été conduite dans des exploitations paysannes pendant deux saisons, au printemps et à l'automne 2018. Au total, 45 champs localisés dans trois régions furent suivis depuis le stage à cinq feuilles du sorgho jusqu'à la maturation des graines. Les infestations de M. sacchari étaient plus élevées au printemps qu'en automne, sauf dans une région. Les populations de M. sacchari fluctuèrent de façon significative selon le stage phénologique du sorgho, avec des abondances plus élevées pendant l'épiaison et la floraison que pendant les autres stages. A l'intérieur et à l'extérieur des champs de sorgho, M. sacchari fut observé sur des plantes de trois familles: Poaceae, Malvaceae, et Cucurbitaceae. Les ennemis naturels des pucerons trouvés dans les champs de sorgho consistaient en huit espèces de coccinelles (Coleoptera: Coccinellidae), une espèce de syrphe (Diptera: Syrphidae), une espèces de chrysope (Neuroptera: Chrysopidae), et une espèce de diptère prédatrice (Diptera: Cecidomyiidae). En plus de ces prédateurs, deux parasitoïdes Adialytus sp. (Hymenoptera: Braconidae) et Pachyneuron aphidis (Bouché) (Hymenoptera: Pteromalidae), émergèrent des momies de pucerons. Les densités de prédateurs et de parasitoïdes furent grandement affectées par la saison de culture avec la majorité de leur présence à l'automne. Cette étude donne les premiers éléments concernant le contrôle du puceron de la canne à sucre en Haïti and dans les Caraïbes.

Firewood and wood packaging material (WPM) are major pathways for moving bark- and wood-infesting insects (borers). Heat treatment regulations for interstate firewood movement vary among U.S. states: from 56°C for 30 min to 71.1°C for 75 min. Current WPM international standards (ISPM 15) require heating to a minimum of 56°C for 30 min throughout the profile of the wood. Using bolts from infested ash (Fraxinus), birch (Betula), oak (Quercus), and pine (Pinus) trees in Michigan, we assessed borer mortality at core temperatures of 50, 53, 56, and 60°C maintained for 30 min in chambers set to 60, 65, 70, or 75°C. After treatment, bolts were monitored for adult emergence and later dissected to determine borer mortality rates. Mortality was high to complete for all heat treatments and increased with both increasing core and chamber temperatures. For the Agrilus (Buprestidae) species tested, there was complete mortality of Agrilus anxius on birch and Agrilus planipennis on ash when core temperatures of 56°C or higher were targeted regardless of chamber temperature. However, on oak, a few Agrilus bilineatus and Agrilus sulcicollis survived in bolts heated to 56°C in chambers at 60 and 65°C, and some A. sulcicollis survived in chambers set at 70 and 75°C. Similarly, a few pine-infesting borers survived heating to 56°C at all chamber temperatures. However, there was complete mortality in all hosts when bolts were heated to 60°C for 30 min, regardless of chamber temperature. Results are discussed in terms of current treatment regulations for firewood and WPM.

Recently, insufficient attractiveness of Conogethes punctiferalis Guenée adult males to sex pheromone, (E)-10-hexadecenal and (Z)-10-hexadecenal, has been reported. To identify the other essential components of sex pheromone, male and female body extracts were analyzed. Two hydrocarbon components, (Z)-9-heptacosene (Z9–27:HC) and (3Z,6Z,9Z)-tricosatriene (Z3,Z6,Z9–23:HC), were identified from only female body extract. There was a significant difference in the electroantennogram (EAG) response of male antennae to Z3,Z6,Z9–23:HC and Z9–27:HC at all test concentrations compared to the response to the hexane control. In field attraction testing, the addition of Z9–27:HC and Z3,Z6,Z9–23:HC to binary aldehyde pheromones significantly increased trap catches of C. punctiferalis male adults. Based on the female and male body extract analysis and field attraction test, Z9-27:HC and Z3,Z6,Z9–23:HC were determined to be other essential sex pheromone components of the Korean C. punctiferalis population. No significant difference was observed in the number of male captures between the bucket trap and delta trap. Pheromone traps with a color close to yellow shade attracted more male adults than traps with a color close to blue shade.

Monochamus alternatus Hope, 1842, is a major forest pest that hosts the pathogenic pinewood nematode (PWN), Bursaphelenchus xylophilus (Steiner and Buhrer, 1934) Nickle 1970. Taxonomically, M. alternatus is currently divided into two subspecies, based on morphology and geography: Monochamus alternatus alternatus Hope, 1842 in China, Taiwan, Tibet, Vietnam, and Laos and Monochamus alternatus endai Makihara, 2004 in South Korea and Japan. Despite their economic importance, the subspecies taxonomy of M. alternatus has never been tested after the first description. In this study, we aimed to reassess the subspecies taxonomy of M. alternatus using molecular and morphological data. For morphological analysis, we examined three major morphological characters (pronotal longitudinal band, granulation on humeri, and elytral proximomedial spine) from 191 individuals from China, Korea, and Taiwan. Population genetic structures were examined using 85 de novo sequences and 82 public COI sequences from China, Korea, Japan, Malaysia, Taiwan, and a few intercepted specimens from the United States. All the genetic data were aligned as three different multiple sequence alignments. Individuals from each subspecies were morphologically and genetically scattered, not clustered according to subspecies in any of the analyses. Therefore, a new synonymy is proposed: Monochamus alternatus Hope, 1842 = Monochamus alternatus endai, syn. n. This study suggests a more robust classification of M. alternatus for the first time and ultimately will pose a substantial impact on implementing quarantine or forestry policies.

Spotted-wing drosophila (SWD), Drosophila suzukii Matsumura (Diptera: Drosophilidae), is an invasive pest of thin-skinned fruits in the United States. Monitoring traps are an integral part of SWD integrated pest management, allowing early detection and timely management of this pest. An ideal monitoring trap should be easy to use, effective in capturing SWD, sensitive and selective to male SWD which are easy to identify due to their spotted wings, and able to predict fruit infestation from trap captures. Deli-cup-based liquid traps (grower standard), which make in-situ observations difficult, were compared with red-panel sticky traps, both baited with commercial lures (Scentry, Trécé Broad-Spectrum (BS), and Trécé High-Specificity (HS)), across several US states in blueberries (lowbush and highbush), blackberry, raspberry, and cherry crops during 2018 and 2021. Results showed that red-panel traps effectively captured SWD, were able to detect male SWD early in the season while also being selective to male SWD all season-long, and in some cases linearly related male SWD trap captures with fruit infestation. Scentry and Trécé BS lures captured similar numbers of SWD, though Trécé BS and Trécé HS were more selective for male SWD in red panel traps than liquid traps in some cases. In conclusion, due to its ease of use with less processing time, red-panel traps are promising tools for detecting and identifying male SWD in-situ and for predicting fruit infestation. However, further research is needed to refine the trap captures and fruit infestation relationship and elucidate the trap-lure interactions in berry and cherry crops.

Sex pheromone baited monitoring traps are a critical tool for integrated pest management decisions against many insects, particularly codling moths (Cydia pomonella L.). The addition of cameras for remote monitoring has the potential to enhance the usefulness of these important tools. However, changes in trap design could potentially alter plume structure and trapping efficiency of these new traps. Here we look at several trap configurations designed to optimize the capture of codling moths in traps equipped with cameras. We found that, in both wind tunnel and field trials, camera equipped triangle traps and camera equipped rectangle traps (both V1 and V2) caught codling moths equivalent to a standard ‘delta’ style trap. While catch was unaffected, altering our rectangular trap opening from 4 to 8 cm (V1 and V2, respectively) decreased frequency of moths contacting the front of trap and increased the frequency of moths flying directly into the trap. We show that these novel camera equipped semiochemical-baited traps catch equivalent to the industry standard white delta trap.

The bean flower thrips, Megalurothrips usitatus (Bagnall) is an economically important insect pest of cowpea, Vigna unguiculata (L.) Walp in south China. Spinetoram is a newly available commercial active ingredient in the spinosyn mode of action group of insecticides that has been recommended for thrips management in China. In this study, the toxicity and efficacy of spinetoram for controlling M. usitatus were evaluated and compared to six other conventional insecticides. In addition, the synergistic effects of adjuvants (Silwet 806, Silwet 618, AgroSpred 910, and AgroSpred Prime) mixed with spinetoram for thrips control on cowpea were evaluated in both the laboratory and the field. Results of this study showed that spinetoram had higher toxicity and field efficacy of M. usitatus than other tested insecticides. A significant increase in efficacy was observed when spinetoram was applied at a recommended rate of 0.67 ml/L, mixed with Silwets (806 and 618) at the rate of 0.5 ml/L. Reductions of 50% and 40% in thrips infestation in the field over treatments without adjuvants were observed 3- and 7-days posttreatments, respectively. However, no significant reduction of M. usitatus was recorded when spinetoram was mixed with AgroSpreds (910 and Prime). Furthermore, no significant differences were found in thrips infestation between spinetoram sprayed alone at the rate of 0.67 ml/L and a reduced rate of spinetoram (0.45 ml/L) mixed with Silwets (806 and 618). The current research shows that Silwets mixed with spinetoram has a synergistic effect in the management of thrips.

Vinegar flies are vectors of pathogens causing fruit rots of grapes, so control of these insects is important for preventing vineyard yield loss. Recent outbreaks of sour rots may be linked to greater challenges controlling vinegar flies, so we investigated the insecticide susceptibility of populations collected from commercial vineyards across Michigan. We first determined the discriminating concentration for phosmet, malathion, methomyl, and zeta-cypermethrin using a laboratory susceptible (Canton-S) strain of D. melanogaster females. The discriminating concentrations were determined as 252.08, 2.58, 0.96, and 1.68 ppm of the four insecticides, respectively. These concentrations were first tested in 2020 against populations from the two major counties for grape production. In 2021, we expanded monitoring to twenty-three populations collected from vineyards across six counties. All populations had significantly lower sensitivity to all four insecticides compared with Canton-S strain, with up to 98.8% lower mortality for phosmet. The LC₅₀, LC₉₀, and LC₉₉ values of the four insecticides for the two populations tested in 2020 were 7–1,157-fold higher than the Canton-S strain. For the twenty-three populations collected in 2021, mortality ranged from 56.3 to 100% when the flies were screened using a 10x concentration of the discriminating concentration of the insecticides, whereas it ranged from 82.4 to 100% when the flies were screened using a 20x concentration. Our results suggest variable levels of resistance to insecticides from multiple chemical classes in D. melanogaster populations in Michigan vineyards, highlighting the need to implement integrated sour rot management approaches that are less dependent on insecticides for control of this species.

Forage alfalfa (Medicago sativa L. [Fabales: Fabaceae]) is a key agricultural commodity of the western region of the United States. The key insect pest of alfalfa, Hypera postica Gyllenhal (Coleoptera: Curculionidae), has developed resistance to the most common class of insecticide used to manage its damage. Alfalfa weevil samples from 71 commercial alfalfa fields located in Arizona, California, Montana, Oregon, Washington, and Wyoming were assayed for susceptibility to lambda-cyhalothrin during 2020–2022 using a laboratory concentration-response assay. Seventeen field sites representing all six states were highly resistant to lambda-cyhalothrin (resistance ratios >79.6) and bioassay mortality often did not exceed 50% even at the highest concentration tested (3.30 µg/cm² in 2020 and 10.00 µg/cm² in 2021–2022). Field sites assayed with more than one pyrethroid active ingredient indicated likely cross-resistance between lambda-cyhalothrin and zeta-cypermethrin (type II pyrethroids) and variable and/or limited potential cross-resistance to permethrin (type I pyrethroid). Thirty-two field sites representing five states were susceptible to lambda-cyhalothrin (resistance ratios ranging from 1 to 20). While resistance is widespread, integrated resistance management strategies including rotating mode of action groups, applying chemical control tactics only when economic thresholds have been met, and utilizing cultural control tactics can be employed to slow the further development of resistance.

Fitness costs associated with insect resistance to insecticides can be exploited to implement resistance management programs. However, most of these studies are restricted to evaluating biological traits on artificial diets. Here, we investigated the fitness cost associated with chlorantraniliprole in Spodoptera frugiperda (J.E. Smith) feeding on corn, soybean, and cotton plants. We used a near-isogenic strain of S. frugiperda resistant to chlorantraniliprole (Iso-RR), a susceptible strain (SS), and heterozygotes strains (H1 and H2) to evaluate several biological and population growth parameters. Larval survival of the Iso-RR strain was on average 90% on corn, 65% on soybean, and 57% on cotton plants. Development time of the larval stage also differed among host plants, Iso-RR strain took on average 14, 17, and 26 days to reach the pupal stage on corn, soybean, and cotton plants respectively. Net reproductive rate, intrinsic rate of population increase, and finite rate of population increase were higher for Iso-RR strain feeding on corn plants than other host plants. The relative fitness, based on the intrinsic rate of population increase, of S. frugiperda resistant strain on corn, soybean, and cotton plants were 1.04, 0.85, and 0.88, respectively. Therefore, no fitness cost was observed for S. frugiperda feeding on corn plants, but a significant fitness cost was observed when this pest fed on soybean and cotton plants. We showed that the food source influences the fitness cost of S. frugiperda resistant to diamide. Such information may help to implement resistance management strategies based on each crop.

Graphical Abstract

The small brown planthopper (Laodelphax striatellus (Fallén), Hemiptera: Delphacidae), is an important agricultural pest of rice, and neonicotinoid insecticides are commonly used for controlling L. striatellus. However, the sublethal effects of thiamethoxam on L. striatellus remain relatively unknown. In this study, an age-stage life table procedure was used to evaluate the sublethal effects of thiamethoxam on the biological parameters of L. striatellus. Additionally, activities of carboxylesterase, glutathione S-transferase, and cytochrome P450 monooxygenase in the third instar nymphs were analyzed. The results indicated that the survival time of F₀ adults and the fecundity of female adults decreased significantly after the third instar nymphs were treated with sublethal concentrations of thiamethoxam (LC₁₅ 0.428 mg/liter and LC₃₀ 0.820 mg/liter). The developmental duration, adult preoviposition period, total preoviposition period, and mean generation time of the F₁ generation increased significantly, whereas the fecundity of the female adults, intrinsic rate of increase (r_i), and finite rate of increase (λ) decreased significantly. The oviposition period was significantly shorter for the insects treated with LC₃₀ than for the control insects. Neither sublethal concentrations had significant effects on the adult longevity, net reproduction rate (R₀), or gross reproduction rate (GRR) of the F₁ generation. The activities of carboxylesterase, glutathione-S-transferase, and cytochrome P450 monooxygenase increased significantly after the thiamethoxam treatments. These results indicate that sublethal concentrations of thiamethoxam can inhibit L. striatellus population growth and enhance detoxification enzyme activities.

The province of Quebec, Canada is the most important organic cranberry growing region worldwide. However, insect pest management methods are limited, and growers face significant yield loss each year, mostly caused by lepidopteran pests. Egg parasitoids of the genus Trichogramma (Hymenoptera: Trichogrammatidae) are effective biocontrol agents of lepidopteran pests in many forests and agricultural systems. Herein, a two-year, large-scale population survey of Trichogramma spp. was performed using Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) as sentinel eggs in Quebec organic cranberry bogs. Collected specimens were identified by sequencing ribosomal DNA of the Internal Transcribed Spacer 2 (ITS-2) region and subjected to resemblance analysis with reference specimens for identification. Our results confirm that at least four Trichogramma species naturally occur in the studied agroecosystem. Those species are T. brassicae Bezdenko, T. minutum Riley, T. ostriniae (Pang et Chen), and T. pretiosum Riley. While some species have already been reported in cranberry bogs, this represents the first mention of T. brassicae and T. ostriniae as well as the first mention of T. minutum in Quebec cranberry bogs. All species collected are native from Eastern Canada except T. ostriniae. These species can be considered as biocontrol agent candidates for cranberry lepidopteran pests, but further efficacy trials are needed to identify the best species for each pest.

La province de Québec, Canada est la plus importante région productrice de canneberges biologiques au monde. Cependant, les méthodes de lutte contre les ravageurs sont limitées et les producteurs font face à une perte de rendement importante chaque année, principalement causée par des insectes de l'ordre des Lépidoptères. Les parasitoïdes oophages du genre Trichogramma Trichogramma (Hymenoptera: Trichogrammatidae) sont des agents de lutte biologique efficaces contre les lépidoptères nuisibles dans de nombreux systèmes forestiers et agricoles. L'objectif de cette étude est de réaliser un inventaire extensif de trichogrammes à l'aide d'œufs sentinelles d'Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) au sein de cannebergières biologiques au Québec. Les échantillons collectés ont été identifiés par séquençage de l'ADN ribosomal de la région de l'espaceur interne transcrit 2 (ITS-2) et soumis à une analyse de ressemblance avec des échantillons de référence pour identification. Nos résultats confirment la présence de quatre espèces de trichogrammes au sein de l'agroécosystème étudié. Ces espèces sont T. brassicae Bezdenko, T. minutum Riley, T. ostriniae (Pang et Chen) et T. pretiosum Riley. Bien que certaines espèces aient déjà été signalées en cannebergières dans le passé, il s'agit de la première mention de T. brassicae et T. ostriniae ainsi que la première mention de T. minutum dans les cannebergières du Québec. À l'exception de T. ostriniae, toutes les espèces récoltées sont indigènes de l'est du Canada. Les perspectives en matière de lutte biologique au sein des cannebergières québécoises sont discutées.

Nosema bombycis Naegeli (Dissociodihaplophasida: Nosematidae), an obligate intracellular parasite of the silkworm Bombyx mori, causes a devastating disease called pébrine. Every year pébrine will cause huge losses to the sericulture industry worldwide. Until now, there are no effective methods to inhibit the N. bombycis infection in silkworms. In this study, we first applied both the novel protein degradationTrim-Away technology and NSlmb (F-box domain-containing in the N-terminal part of supernumerary limbs from Drosophila melanogaster) to lepidopteran Sf9-III cells to check for specific degradation of a target protein in combination with a single-chain Fv fragment (scFv). Our results showed that the Trim-Away and NSlmb systems are both amenable to Sf9-III cells.We then created transgenic cell lines that overexpressed the protein degradation system and N. bombycis chimeric scFv targeting spore wall protein NbSWP12 and evaluated the effects of the insect transgenic cell lines on the proliferation of N. bombycis. Both methods could be applied to cell lines and bothTrim-Away and NSlmb ubiquitin degradation systems effectively inhibited the proliferation of N. bombycis. Further, either of these degradation systems could be applied to individual silkworms through a transgenic platform, which would yield individual silkworms with high resistance to N. bombycis, thus greatly speeding up the process of acquiring resistant strains.

Aphid species (Hemiptera: Aphididae) are among the most serious pests for citrus cultivation throughout the world causing substantial crop damages. Accurate identification of aphids to the species level can be difficult, though being crucial for their effective management. In this study, a molecular diagnostic assay for distinguishing eleven aphid species was developed. A fragment of the mitochondrial Cytochrome Oxidase I (mtCOI) gene was used and a Polymerase Chain Reaction–Restriction Fragment Length Polymorphism (PCR–FLP) analysis with five restriction enzymes, based on DNA sequence polymorphisms, was applied to differentiate the eleven aphid species. This molecular technique allows aphid species at any life stage to be discriminated accurately and simply and can be a useful tool for monitoring the populations of economically important aphid species.

The soybean aphid Aphis glycines Matsumura is a predominant insect pest in Asia and North America and causes great losses to soybean. The release of genome data for A. glycines will facilitate gene function research in the future. However, suitable reference genes for A. glycines under various experimental conditions are scarce. To search for appropriate reference genes for A. glycines, nine candidate reference genes, including Act, α-Tub, β-Tub, RPS12, RPS18, RPL5, RPL27, EF1α, and Fer, were tested under six experimental conditions to evaluate their suitability for use in the normalization of qRT–PCR data. Results showed that EF1α and RPS12 were optimal for the developmental stages of A. glycines, RPS18 and RPS12 were appropriate for wing dimorphism, β-Tub and RPS18 were suitable for different tissues and RPL5, and α-Tub could be used for normalization at different temperatures. β-Tub and EF1α could be proposed as reference genes for insecticide treatment, and RPL5 and RPS12 were found to be the most stable reference genes in different photoperiods. The results provide appropriate reference genes for analyzing gene expression in A. glycines and contribute to future research on the molecular physiology and biochemistry of A. glycines.

Boring pests such as Sitophilus zeamais (S. zeamais) are major threats in grain storage. However, how these pests affect the proteins of stored grains remains largely unknown. Here we aimed to investigate the effect of S. zeamais infestation on wheat protein during postharvest storage. In this study, wheat grain infested by S. zeamais was sampled at egg (4 d), larval (20 d), pupal (35 d), and adult stages (45 d), respectively. The protein's physicochemical and structural properties and the edible quality of whole wheat noodle were analyzed. The results showed that S. zeamais infestation significantly decreased the quality of wheat protein by altering its constitution and structure properties. Especially, compared with the control, the content of wet and dry gluten, gluten index, sodium dodecyl sulfate sedimentation volume, sulfhydryl groups, and disulfide bonds in insect-infested wheat decreased by 19.40, 5.42, 18.40, 8.12, 29.13, and 14.30%, respectively, during the storage period of one life cycle of S. zeamais. Additionally, the proportions of wheat protein fractions (albumin [1.16-fold], globulin [0.96-fold], gliadin [1.16-fold], and glutenin [0.95-fold]) and secondary structures (α-helix [0.91-fold], β-fold [0.96-fold], β-turn [1.06-fold], and random coil [1.05-fold]) of protein changed significantly, and the gluten network structure was broken in S. zeamais-infested wheat. Furthermore, the color of whole wheat noodle became darker, cooking loss rate increased, and textural properties (hardness, adhesiveness, springiness, cohesiveness, chewiness, and resilience) decreased as well. The results in the present study provided new insights for analyzing the quality deterioration mechanism and further quality improvement of boring pests-infested wheat grain.

The brown marmorated stink bug, Halyomorpha halys (Stål), is an invasive pest introduced to North America in the mid-1990's that has caused economic losses to a wide range of commodities. In vegetables, H. halys feeding damage has been well described, but the effect of different vegetable hosts on H. halys fitness is less understood. We caged 2nd instar H. halys on different vegetable hosts (e.g., tomato, sweet corn, eggplant, bell pepper, and snap bean) and monitored their development until adulthood to compare the effects of vegetable host type on H. halys nymph survival and development time. Experiments were replicated nine times over a two-year period. Survival of 2nd instars from F1 generation (early-season) eggs was low (<30%) on all vegetables resulting in no significant treatment effect. However, H. halys nymphs collected from F2 generation (late-season) eggs had higher survivorship on all vegetables except tomato. The percentage of H. halys 2nd instars that reached adulthood was greatest on corn (53%) and pepper (45%), followed by snap bean (24%), and significantly lower on eggplant (9%) and tomato (2%). Total development time from 2nd instar to adult was fastest on corn and slowest on peppers, although tomatoes were not tested due to the low survival. Trends in development rate were not seasonally-dependent. Our study compares H. halys survivability on several vegetable commodities, and provides insights into H. halys developmental success and dependence on various host plants over the season.

Tephritid fruit flies are among the most invasive and destructive agricultural pests worldwide. Over recent years, many studies have implemented the CRISPR/Cas9 genome-editing technology to dissect gene functions in tephritids and create new strains to facilitate their genetics, management, and control. This growing literature allows us to compare diverse strategies for delivering CRISPR/Cas9 components into tephritid embryos, optimize procedures, and advance the technology to systems outside the most thoroughly studied species within the family. Here, we revisit five years of CRISPR research in Tephritidae and propose a unified protocol for candidate gene knockout in fruit flies using CRISPR/Cas9. We demonstrated the efficiency of our protocol by disrupting the eye pigmentation gene white eye (we) in the melon fly, Zeugodacus cucurbitae (Coquillett) (Diptera: Tephritidae). High rates of somatic and germline mutagenesis were induced by microinjecting pre-assembled Cas9-sgRNA complexes through the chorion of embryos at early embryogenesis, leading to the rapid development of new mutant lines. We achieved comparable results when targeting the we orthologue in the oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), illustrating the reliability of our methods when transferred to other related species. Finally, we functionally validated the recently discovered white pupae (wp) loci in the melon fly, successfully recreating the white puparium phenotype used in suppression programs of this and other major economically important tephritids. This is the first demonstration of CRISPR-based genome-editing in the genus Zeugodacus, and we anticipate that the procedures described here will contribute to advancing genome-editing in other non-model tephritid fruit flies.

The spotted lanternfly Lycorma delicatula White (Hemiptera: Fulgoridae) is a polyphagous insect pest that invaded the United States in 2014, in Berks County, Pennsylvania. It has since spread to several northeastern states and poses a significant threat to northeastern grape production. Most studied species of Hemiptera are known to communicate intraspecifically using some form of substrate-borne vibrational signals, although such behavior has not yet been reported in L. delicatula. This report demonstrates that adult and fourth-instar L. delicatula were attracted towards broadcasts of 60-Hz vibroacoustic stimuli directed to a laboratory arena and test substrate, which suggests that both adults and fourth instar nymphs can perceive and respond to vibrational stimuli.

Citricola scale, [Coccus pseudomagnoliarum (Kuwana)], is a key pest of citrus requiring insecticide control in areas where biological control is ineffective. Here we quantified the relationship between C. pseudomagnoliarum density and Valencia orange (Citrus sinensis L. Osbeck) yield and sooty mold contamination to inform pest action thresholds. Two field experiments documented significant effects of adult or nymphal C. pseudomagnoliarum densities on fruit yield and sooty mold. Adults generally had more pronounced effects, reducing average tree yield by up to 43% and increasing sooty mold prevalence by at least 45%. Analyses estimated significant effects of C. pseudomagnoliarum at densities less than 0.1 adults/branch or 1.0 nymph/leaf. These results suggest a decrease in the current threshold of 1.0 for adults/branch and may be warranted to minimize C. pseudomagnoliarum damage.

The moth species Phthorimaea absoluta (Meyrick) (formerly Tuta absoluta) is serious threat to tomato and other Solanaceous crops worldwide and is invasive throughout Europe, Asia, and Africa. While P. absoluta has not yet been found in the U.S. recent detections in the Caribbean have raised concerns that the species could be introduced to mainland North America. To improve detection capacity, a droplet digital PCR (ddPCR) assay was developed that employs a nondestructive bulk DNA extraction method able to detect one P. absoluta sample among 200 nontargets. Such high-throughput and sensitive molecular assays are essential to preventing introductions through early detection and response. This assay can also be used in areas where P. absoluta is established to monitor outbreaks and track migratory patterns.