Crops genetically engineered to produce insecticidal proteins from Bacillus thuringiensis (Bt) have advanced pest control, but their benefits have been reduced by evolution of resistance in pests.The global monitoring data reviewed here reveal 19 cases of practical resistance to Bt crops, which is field-evolved resistance that reduces Bt crop efficacy and has practical consequences for pest control. Each case represents the responses of one pest species in one country to one Bt toxin. The results with pink bollworm (Pectinophora gossypiella) and Bt cotton differ strikingly among the world's three leading cotton-producing nations. In the southwestern United States, farmers delayed resistance by planting non-Bt cotton refuges from 1996 to 2005, then cooperated in a program that used Bt cotton, mass releases of sterile moths, and other tactics to eradicate this pest from the region. In China, farmers reversed low levels of pink bollworm resistance to Bt cotton by planting second-generation hybrid seeds from crosses between Bt and non-Bt cotton. This approach yields a refuge of 25% non-Bt cotton plants randomly interspersed within fields of Bt cotton. Farmers adopted this tactic voluntarily and unknowingly, not to manage resistance, but apparently because of its perceived short-term agronomic and economic benefits. In India, where non-Bt cotton refuges have been scarce and pink bollworm resistance to pyramided Bt cotton producing Cry1Ac and Cry2Ab toxins is widespread, integrated pest management emphasizing shortening of the cotton season, destruction of crop residues, and other tactics is now essential.

Commercial honey bee (Apis mellifera L.) colonies significantly contribute to agricultural productivity through crop pollination. Almond production requires the most colonies because there are more than a million acres of orchards that require cross-pollination for nut set. With the rising costs of managing and transporting colonies to almond orchards combined with the high colony losses beekeepers routinely experience, we asked if renting colonies for almond pollination was profitable. We conducted a longitudinal study on 190 colonies from their establishment in April until they were placed in almond orchards 10 mo later. In the fall, equal numbers of colonies were placed either in cold storage (CS) facilities or in outdoor apiaries for the winter. We found that the cost of overwintering colonies in CS was lower than in apiaries, but CS did not reduce overwintering losses. A key finding from our study is that there is little or no profit in renting colonies for almond pollination once summer management and overwintering costs are considered. Our only profitable venture was honey production in the summer. We propose alternative management strategies to lower costs and make almond pollination profitable. We also developed a decision tool for selecting colonies to overwinter in CS and reduce expenditures on those that will not reach sufficient size for almond pollination. Our study exposes the unsustainable financial burden experienced by migratory beekeepers that is not included in estimates of yearly colony losses, and underscores the urgent need for forage plantings to generate revenue from honey and improve overwinter survival.

Improving pollinator habitat on farmlands is needed to further wild bee conservation and to sustain crop pollination in light of relationships between global declines in pollinators and reductions in floral resources. One management strategy gaining much attention is the use of wildflower strips planted alongside crops to provide supplemental floral resources for pollinators. However, farmer adoption of pollinator-friendly strategies has been minimal, likely due to uncertainty about costs and benefits of providing non-crop flowering plants for bees. Over 3 yr, on four diversified farms in Montana, United States, we estimated the potential economic profit of harvesting and selling wildflower seeds collected from flower strips implemented for wild bee conservation, as an incentive for farmers to adopt this management practice. We compared the potential profitability of selling small retail seed packets versus bulk wholesale seed. Our economic analyses indicated that potential revenue from retail seed sales exceeded the costs associated with establishing and maintaining wildflower strips after the second growing season. A wholesale approach, in contrast, resulted in considerable net economic losses. We provide proof-of-concept that, under retail scenarios, the sale of native wildflower seeds may provide an alternative economic benefit that, to our knowledge, remains unexplored. The retail seed-sales approach could encourage greater farmer adoption of wildflower strips as a pollinator-conservation strategy in agroecosystems.The approach could also fill a need for regionally produced, native wildflower seed for habitat restoration and landscaping aimed at conserving native plants and pollinators.

In 2001, Nasutitermes corniger (Motschulsky), common name conehead termite, were discovered near a marina in Dania Beach, FL, where the invasive species was probably transported from its native range in Central and South America or the Caribbean. In January 2016, an infestation was found in Pompano Beach, Florida, approximately 21 km north of the Dania Beach population. This study compares variants in seven microsatellite loci across specimens from 11 nests in Dania Beach and 8 nests in Pompano Beach. Results are consistent with all N. corniger in both locations being descendants of a single introduced colony, spreading within Broward County, FL through human transport of infested materials. No more than four alleles were found at any of the seven microsatellite loci analyzed, inferring that a single Queen and King, or multiple sibling reproductives descended from a monogamous pair, headed the colony that arrived in Florida. The potential economic and environmental impacts of this invasive termite are enormous due to its broad diet, including agricultural crops and orchards, native and ornamental plants, natural landscapes, and structures. Conspicuous tunnels and aboveground nests are the key aspects of N. corniger biology that render colonies vulnerable to discovery and control. The now proven ability of N. corniger to establish breeding populations in the United States, to cause extensive property and landscape destruction, and to spread by human transport underscores the need for continued aggressive efforts toward eradication of known infestations as well as quick operational actions the next time invasive N. corniger are discovered.

Orientus ishidae (Matsumura) (subfamily Deltocephalinae) is an Asian species now widespread in Europe, and a vector of 16SrV phytoplasmas agents of grapevine Flavescence dorée (FDP). Embryonic and post-embryonic development, spatial distribution, and relationships with grapevine of nymphs were studied under field and laboratory conditions. Egg-hatching dynamics and post-embryonic development of nymphs were studied by collecting grapevine wood from managed and unmanaged vineyards (including bot European Vitis vinifera L., and wild American rootstocks) and storing it inside rearing cages at T = 21–23°C. Field sampling of nymphs were made on both grapevine and two elective host plants of O. ishidae: hazelnut and hornbeam. Taylor's Power Law was applied to assess the aggregation coefficient of early- (first and second) and late- (third to fifth) life instars on leaves and shoots of host plants. More nymphs were obtained from wood collected in unmanaged rather than managed vineyards. Under lab conditions, the embryonic development lasted 34–48 d, whereas the whole post-embryonic development averaged 27 d. Under field conditions, early instars peaked at the end of May, and late instars peaked 2–4 wk later. The aggregation patterns decreased from early to late instars, and from leaves to shoots. Very few nymphs were observed on unmanaged grapevine, either European or American, and none on managed European grapevine. Some behavioral and FDP epidemiological consequences of the results obtained are discussed.

Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), transmits Candidatus Liberibacter asiaticus (Las), the bacterial pathogen putatively responsible for citrus huanglongbing. Multiple studies have shown psyllids acquire Las more frequently, and are more likely to inoculate susceptible plants, when they acquire Las as nymphs. Understanding the transmission of Las to nymphs is critical to the Las lifecycle. The objective of this study was to determine the transmission Las by female D. citri to their offspring.Two transmission pathways were quantified: horizontal transmission (acquisition of Las via feeding at the oviposition site) and vertical transmission (transovarial). Eggs of individual, infected females were transferred to an uninfected seedling to assess vertical transmission. In a second experiment, horizontal transmission was evaluated by replacing eggs laid by infected females with uninfected nymphs. Nymphs exposed to Las via horizontal transmission of the oviposition site were more likely to acquire Las than from vertical transmission. Las deposited in flush by an infected adult female feeding during oviposition was sufficient for infecting nymphs. Combined results of both experiments suggest that vertical transmission allows Las to spread in low amounts even when infected plant hosts are not available and that inoculation of the oviposition site provides a source of Las to developing nymphs via the plant phloem. These data support the hypothesis that transmission through infected plant material via maternal inoculation is a primary pathway of Las transmission between vector and host.

Transmission of the virus, Citrus leprosis virus C (CiLV-C) (Cilevirus) by Brevipalpus yothersi Baker, on different citrus species was evaluated under greenhouse conditions. First, the relationship between acquisition access periods (AAPs; 1, 12, 24, 36, and 48 h) and virus concentration in mites was determined. Second, the ability of B. yothersi to transmit CiLV-C to orange, mandarin, grapefruit, and lime trees was measured. We then assessed the establishment of mites on the different citrus species as measured by their population increase on each species. We found no relationship between AAPs and virus load in mites. The virus was found in all mites tested but there was no difference in virus quantities among the treatments. We selected an AAP of 24 h for the transmission experiment. Brevipalpus yothersi transmitted the virus to all citrus species evaluated, but susceptibility was different. The number of infected leaves was greater on orange and mandarin compared with grapefruit and lime. Furthermore, populations of B. yothersi successfully established on orange and mandarin, but not on grapefruit and lime trees. The implications of our results in the virus–mite–citrus plant relationship are discussed.

The decline of cultivated strawberry (Fragaria × ananassa Duchesne ex Rozier; Rosaceae) observed in the province of Quebec, Canada, between 2012 and 2014 was mostly caused by persistent viruses: strawberry mild yellow edge virus (SMYEV) (Potexvirus; Alphaflexiviridae) and strawberry crinkle virus (SCV) (Cytorhabdovirus; Rhabdoviridae); and semi-persistent viruses: strawberry mottle virus (SmoV) (Secoviridae), strawberry vein banding virus (SVBV) (Caulimovirus; Caulimoviridae), and strawberry pallidosis virus (SPaV) (Crinivirus: Closteroviridae) transmitted by insect vectors. The objective of this study was to determine the sources of viral contamination in commercial strawberry fields in Quebec. Specifically, we wished to 1) determine the prevalence of persistent viruses in winged strawberry aphid Chaetosiphon fragaefolii (Cockerell) (Hemiptera: Aphididae) specimens captured; 2) determine the prevalence of all viruses in wild strawberry Fragaria virginiana Miller plants near commercial plantings; and 3) evaluate the viral contamination of strawberry transplants obtained from nurseries and tested before and after planting in commercial strawberry fields. Results indicated high percentage (38%) of the aphids (n = 205) and high percentage (67%) of F. virginiana patches (n = 12) were infected by strawberry viruses. Ultimately, our results showed a low percentage (5%) of the plants from various nurseries (n = 56) were infected before planting, whereas a third (29%) of the healthy exposed plants in the fields (n = 96) became rapidly infected by insect vectors within a year of having been planted. This study provides significant insights on the relative importance of the various sources of contamination in Quebec strawberry fields: C. fragaefolii versus F. virginiana versus nurseries versus post-nursery infections through exposure to virus-carrying insects.

Six fungal isolates of Beauveria bassiana (Balsamo) Vuillemin and one isolate of Metarhizium anisopliae (Metschnikoff) Sorokin were isolated and evaluated for their pathogenicity to Icerya seychellarum (Westwood) and Aulacaspis tubercularis Newstead. There is a positive correlation between the concentration of the fungal blastospore concentrations and the percentage of mortality. Bio-efficacy increased significantly after inoculation with increasing concentration of blastospores and elapsed time up to 12 d after inoculation. The mortality of nymphs exposed to fungal isolates at various concentrations varied between 2.5 and 88.8%. Probit analysis of data at 95% confidence limits of LC₅₀ and LT₅₀s showed significant differences in the susceptibility of nymphs of I. seychellarum and A. tubercularis to the tested fungal isolates. The fungal isolates of Egy-6 and Egy-9 were the most effective against I. seychellarum and A. tubercularis, respectively. They had the lowest LC₅₀ (4.20 × 10⁵ and 5.71 × 10³ blastospore ml^-1) and LT₅₀ (ranged from 4.61 to 9.79 and 4.84 to 8.71 d), respectively. The current study showed that all the fungal isolates yielded moderate mortality rates of nymphs and adult female populations of both the tested insect pests. To our knowledge, this is the first report of bio-efficacy of Beauveria and Metarhizium isolates against members of the Diaspidadae and Monophlebidae family insects.These results establish that the use of these native entomopathogenic fungi isolates of B. bassiana (Egy-3, Egy-4, Egy-6, Egy-7, Egy-9, and Egy-10) and M. anisopliae (Egy-5) could be considered for further development as microbial control agents of the mealybug and scale insects as a potential biological agent for use in an IPM program.

Encarsia formosa Gahan is an important endoparasitoid of the whitefly, Bemisia tabaci Gennadius. In the present study, we compared the fitness and population parameters of E. formosa when parasitizing the two most invasive and destructive whitefly species in China, the B and Q of B. tabaci. We also studied whether natal host influenced on parasitism and host-feeding capacities of E. formosa on B. tabaci B versus Q. Age–stage life table analysis indicated that E. formosa developmental duration was shorter, fecundity was higher, and longevity was greater on B. tabaci B than on Q. The life table parameters, including the intrinsic rate of increase (r), finite rate of increase (λ), net reproduction rate (R₀), and the mean generation time (T), indicated that the fitness of E. formosa on B. tabaci B is higher than B. tabaci Q. We also found that the host species used to rear E. formosa affected the parasitoid's subsequent parasitism and host feeding on B. tabaci B and Q. When E. formosa were reared on B. tabaci B, its subsequent parasitism rate on third-instar nymphs was significantly higher on B. tabaci B than on Q. These results will be useful for managing the biological control of B. tabaci in the field.

The predatory mite, Neoseiulus bicaudus (Wainstein), is a potential biological control agent against spider mites and thrips. The objective of this experiment was to compare the effects of three diets on the life table of N. bicaudus. The three diets were 1) Tetranychus turkestani (Ugarov & Nikolskii) (Acari: Tetranychidae), the natural prey of N. bicaudus; 2) Tyrophagus putrescentiae (Schrank) (Acari: Acaridae), an alternative prey; and 3) artificial diet primarily consisting of decapsulated shrimp cysts, egg yolk, and honey. The computer simulation was used to project the population growth of N. bicaudus fed on different diets. The preadult developmental time (3.83 d) of N. bicaudus was shortest, and the intrinsic rate of increase (r = 0.2782 d^-1) and the net reproductive rate (R₀ = 18.98 offspring) were highest when reared on the alternative prey Ty. putrescentiae. The total development time (7.37 d) was longest, and the population parameters were the lowest (r = -0.0081 d^-1, R₀ = 0.85 offspring) when N. bicaudus was reared on artificial diet. The population projection showed that the population of N. bicaudus reared on Ty. putrescentiae could increase fast. Our results showed that the Ty. putrescentiae was the most suitable prey for mass rearing of N. bicaudus. The artificial diet could not support the N. bicaudus population and needs to be improved.

Biological control is one of the strategies to reduce populations of diamondback moth, Plutella xylostella (Linnaeus) (Lepidoptera: Plutellidae), the major pest of brassica. Entomopathogen-based biopesticides are recommended and used for its control, reducing the constant use of chemical pesticides. Predators and/or fungal entomopathogens have an increasing interest to be used against diamondback moth, and the compatibility of these control agents in the field is important for pest management. Here we experimentally investigate the effects of diamondback moth larvae treated with a biopesticidal formulation of Beauveria bassiana (Balsamo) Vuillemin in the feeding preference and functional response of the ring-legged earwig. We used untreated and B. bassiana-treated diamondback moth fourth instars (over a 24-h period of exposure) and Euborellia annulipes (Lucas) fifth instars. The nymphs were included in choice condition tests and different larval densities to the analysis of feeding preference and functional responses, respectively. Euborellia annulipes nymphs exhibited no feeding preference under choice conditions but presented different types of functional response: Type II on untreated and type III on fungus-treated diamondback moth larvae. The interaction between E. annulipes and B. bassiana observed in our study contributes to the understanding of the predator–prey–pathogen relationships with implications for P. xylostella integrated management strategies.

We studied the mating behavior and reproductive biology of three members of the genus Agrilus: the bronze birch borer, Agrilus anxius Gory; the twolined chestnut borer, Agrilus bilineatus (Weber); and the emerald ash borer, Agrilus planipennis Fairmaire. All three species share a highly stereotyped mating behavior. However, the copulation duration of A. planipennis was 90% longer than that of its two congeners. Female reproductive tracts of the three species were anatomically similar, as were the spermatophores. Within the spermatophores, sperm were single in A. anxius and A. bilineatus, while in A. planipennis, sperm were bundled in groups of approximately 20 in a hyaline sheath. We found that field-caught A. anxius and A. bilineatus had higher rates of female insemination than A. planipennis. In additional studies with A. planipennis and A. anxius, we found that mating duration was related to mating success, and fecundity for A. planipennis, but not for A. anxius. For both A. planipennis and A. anxius, the spermatophore was passed to the female toward the end of the copulatory period. Sperm were found in the spermatheca immediately after copulation ended in A. planipennis and 30 min after copulation ended in A. anxius. We present possible explanations for these differences.

Black soldier flies, Hermetia illucens (L.), consume decaying organic materials at the larval stage and can be used for recycling a variety of biogenic wastes into value-added products. Black soldier flies are normally found in subtropical and warm temperate regions. Cold temperatures may prevent their establishment in colder areas, thus alleviating a concern of their becoming an invasive species. Potentially, cold temperatures can also be used to manipulate the rate of black soldier fly development, which may be needed for timing certain life stages for mass-production needs. In the present study, immature black soldier flies were highly susceptible to freezing. Their survivorship decreased as time spent at -12°C increased from 10 to 60 min. Only ca. 2% of eggs, <1% of larvae, and no pupae survived after 60 min of exposure. Chilling at 4°C also had a significant negative effect that became more pronounced as duration of exposure increased from 24 to 72 h. Only ca. 2% of eggs and second instars and ca. 23% of pupae survived after 72 h. In the same time, >80% of third instars and >90% of fifth instars were still alive following 72 h of exposure. Chilling fifth instars resulted in smaller adults but freezing them for 48 h resulted in bigger adults. Based on these results, black soldier fly is unlikely to establish in areas with long periods of subfreezing winter temperatures. Low temperatures may be used to manipulate development of the late instars, but at a cost of higher mortality.

Insect neuropeptides in the pyrokinin/pheromone biosynthesis-activating neuropeptide (PBAN) family are actively involved in many essential endocrinal functions and serve as potential targets in the search for novel insect control agents. Here, we dissect the nervous system of larval, pupal, and adult Plutella xylostella (L.) (Lepidoptera: Plutellidae) and describe the ganglion morphology and localization of PBAN during different insect developmental stages. Our results show that the central nervous system (CNS) of this species consists of four types of ganglia: cerebral ganglia (brain), subesophageal ganglion (SEG), thoracic ganglia, and abdominal ganglia. A two-lobed brain is connected to the reniform SEG with a nerve cord in larvae and prepupae, whereas in the late pupae and adults, the brain and SEG are fused, forming a brain–SEG complex. The larvae and prepupae have eight abdominal ganglia each, whereas the late pupae and adults each have four abdominal ganglia. Furthermore, all life stages of P. xylostella had similar patterns of PBAN immunoreactivity in the CNS, and the accumulation of PBAN was similar during all life stages except in adult males. PBAN immunoreactive signals were observed in the brain and SEG, and fluorescence signals originating in the SEG extended the entire length of the ventral nerve cord, ending in the terminal abdominal ganglia. Our results provide morphological data that inform the development and evolution of the CNS. In addition, they indicate that the nervous system contains PBAN, which could be used to control P. xylostella populations.

Several species of grasshoppers are attracted to vegetable oils. These oils have kairomonal properties mainly due to the presence of linolenic and linoleic fatty acids. This study aimed to determine whether the odors of canola, flax, and olive oils are attractive to Dichroplus vittigerum (Blanchard 1851) and if they induce preference and feeding. We conducted three bioassays to determine whether oil modifies attraction and feeding behavior of this grasshopper. We first determined the attraction of the oils using a wind tunnel, secondly evaluated phagostimulation produced by the oils, and finally performed preference tests comparing consumption of Taraxacum officinale (Weber ex F.H.Wigg. 1780, Asterales: Asteraceae) leaves treated with the oils versus control leaves. Even though all of the oils induced attraction, only flax oil acted as a phagostimulant. However, the oils did not determine the preference and did not increase feeding on leaves. We hypothesize that T. officinale leaves are inherently attractive and treatment with oils did not affect feeding on them. Our results provide a starting point to develop baits that can be used to attract and control these harmful insects, presenting flax oil as a potential bait for D. vittigerum since its odor was both attractive and led to increased feeding or phagostimulation. Future studies should test the effect of the oils on other plant species or at varying doses, under field conditions.

Numerous insect species engage in seasonal, trans-latitudinal migration, in response to varying resource availability, climatic conditions and associated opportunities, to maximize fitness and reproductive success. For certain species, the interaction between migrant adults and individual host plants is well-studied under laboratory conditions, but scant knowledge exists on the nutritional ecology of wild (i.e., field-caught) moths. During 2017–2018, we trapped adults of the cotton bollworm Helicoverpa armigera (Hübner) along its migration pathway in northeastern China and used pollen grain analysis to assess its visitation of particular host plants. Next, we assessed life history effects of adult feeding on carbohydrate-rich resources, for migrant individuals. Pollen grain analysis revealed H. armigera visitation of 32 species from 28 families, with the largest carrier ratio for northward migrants. Evening primrose (Oenothera spp.) accounted for 48% of pollen grains, indicating a marked H. armigera feeding preference. Furthermore, feeding on sugar-rich foods benefited adult fitness, enhanced fecundity by 65–82% and increased flight distance by 38–55% as compared to unfed individuals. Also, the degree of enhancement of reproduction and flight performance following sugar feeding varied between different migratory cohorts. Our work combines (polymerase chain reaction [PCR]-assisted) palynology and laboratory-based life history trials to generate novel perspectives on the nutritional ecology of long-distance migratory insects. These findings can aid the development of population monitoring and ‘area-wide’ management strategies for a globally-important agricultural pest.

Granules composed of alfalfa and sunflower meal that were impregnated with avermectins (AVMs) were developed for use against the Moroccan locust, Dociostaurus maroccanus (Thunberg). Laboratory experiments with granules containing 0.15% of AVMs fed to locust nymphs resulted in 100% death within 5 d. The quantification of AVM loss after exposure of AVM-containing preparative forms to UV light for various time periods was performed using high-performance liquid chromatography (HPLC). The results showed no loss of AVMs from the granules after 3 h of their exposure to UV light. The effect of UV radiation on a thin layer of the AVM solution led to the rapid degradation of AVMs. Only 0.2% of the initial AVM amount was detected after 3 h of exposure. In the granulated form, the AVM content remained stable for 10 mo when stored at room temperature in the dark. A method combining solid-phase extraction with HPLC was developed for the quantification of AVMs in locust nymphs. The granulated AVMs are characterized by their high resistance to UVB radiation. The use of plant-based granules impregnated with AVMs can be considered a very promising tool for locust control.

The green peach aphid, Myzus persicae (Sulzer), is one of the most common pest species that has the potential to transmit more than 100 plant viruses. Controlling this pest is difficult because it has become resistant to a wide range of insecticides. Nanoformulation has the capacity to reduce the pesticide load in agriculture and thus reduce the risks on human health and the environment. In this study, nanocapsules of pirimicarb and pymetrozine were prepared using nanostructured lipid carriers. The size, morphology, and encapsulation efficiency of nanocapsules were investigated using dynamic light scattering, scanning electron microscopy, and UV-VIS spectrophotometer. Zeta potential studies revealed stability of the nanocapsules of both insecticides. The encapsulation efficiencies were 85 and 81% for pirimicarb and pymetrozine, respectively. The nanocapsules were spherical with sizes of 35.38 and 35.12 nm for pirimicarb and pymetrozine, respectively.The LC₅₀ values for the wettable powder (WP) and nanocapsule of pirimicarb after 48 h were 216.2 and 73.2 mg ai/l; for pymetrozine after 96 h, the values were 40.6 and 14.8 mg ai/l, respectively. Durations of residual activity for WP and nanocapsule formulations of pirimicarb were 7 and 15 d, respectively. The residual activity periods for WP and nanocapsule formulations of pymetrozine were 9 and 17 d, respectively. The results revealed that nanoencapsulation can improve performance allowing for reduced doses and increased duration of insecticidal activity for both of the insecticides tested.

Neonicotinoids are used to protect citrus trees against pests. Dissipation and persistence of neonicotinoids in pollen and nectar of citrus trees after foliar applications and their potential exposure to pollinators have not been well characterized. Field studies were conducted using three orange and one mandarin varieties to compare the imidacloprid and thiamethoxam residue levels and their decline in pollen and nectar after treatments in pre-bloom close to flowering period and their persistence 1 yr after treatment. The possible risk to honeybees was assessed. In nectar, thiamethoxam and imidacloprid residues were between 61 and 99% lower than in pollen, depending on the citrus variety or/and the days after treatment when applied close to blooming. At the end of the flowering period, imidacloprid in pollen and nectar was not detected in the mandarin variety after treatment in pre-bloom, whereas for thiamethoxam, no residues were detected in nectar but 10 ng/g was detected in pollen. There were no quantifiable levels of residues for either neonicotinoids in pollen or nectar during the flowering period of the following year. Neonicotinoid residue levels and their decline in nectar and pollen in citrus depended on the timing of applications relative to flowering and on the citrus variety. The absence of neonicotinoid residues 1 yr out after foliar applications in all varieties assayed demonstrated that none of the neonicotinoids tested were persistent. The results could be different in other citrus varieties, and therefore, also the exposure assessment for managed pollinators.

Large-scale field studies on the ecological effects of aerial forest spraying often face methodological challenges, such as insufficient funding, difficult logistics, and legal obstacles. The resulting routine use of underpowered designs could lead to a systematic underestimation of insecticide effects on nontarget arthropod communities. We tested the use of an Unmanned Aerial Vehicles (UAVs) for experimental insecticide applications at tree level to increase replication in cost-efficient way. We assessed the effects of two forestry insecticides, diflubenzuron (DFB) and tebufenozide (TBF), on the oak defoliator, Thaumetopoea processionea (Linnaeus) (Lepidoptera: Thaumetopoeidae), and on nontarget, tree-living Lepidoptera. Individual trees were sprayed with either insecticide or left unsprayed, in a fully factorial design involving 60 trees. Caterpillars fallen from tree crowns were sampled as a measure of mortality, while caterpillar feeding activity was monitored by collecting frass droppings. Both DFB and TBF led to greater mortality of T. processionea and lower Lepidoptera feeding activity than control levels. TBF caused measurable mortality in nontarget groups, affecting Macrolepidoptera more strongly than Microlepidoptera, while there was no significant side effect of DFB. The high treatment efficacy against the target pest indicates that UAV technology is well-suited for the application of insecticide in forests. We detected distinct responses to different insecticides among nontarget groups and suggest there is an influence of application timing and biological traits in these differences, emphasizing the need for more ecologically orientated risk assessment. UAV-supported designs can be used to link laboratory bioassays and large-scale experiments, allowing for more comprehensive assessments of insecticide effects in forest ecosystems.

In different parts of the world, the increasing agricultural practice of retaining crop stubble in fields across seasons has led to population increases of soil-dwelling arthropods, primarily detritivorous species. These species typically play a beneficial role in the ecosystem, but some, including the Portuguese millipede (Ommatoiulus moreleti (Lucas)) can be sporadic pests. To assist in better understanding of pest risk, this study examines why O. moreleti feeds on crop seedlings. For lupin, seedling susceptibility appears to be related to plant properties, with greatly different levels of damage caused to the two cultivated species (Lupinus angustinus and Lupinus albus) and particularly between cultivated and wild-type L. angustinus seedlings. Millipedes feeding on lupin (cultivated L. angustinus), but not lucerne (Medicago sativa), gained a similar amount of weight to those feeding on other foods known to be readily consumed. The life-stage and sex of O. moreleti was found to be related to seedling damage. The presence of crop stubbles (as alternate food sources) did not limit the damage O. moreleti caused to lupin, suggesting that the presence of stubble in a field situation may not preclude feeding on crop seedlings. We discuss how results from these controlled environment trials can build a basis for understanding variable crop damage by O. moreleti in the field.

Fulmekiola serrata (Kobus) was observed infesting sugarcane, Saccharum spp. hybrids, in the United States for the first time in January 2017 in Florida. Field studies were conducted to determine F. serrata infestation levels on popular sugarcane cultivars and to determine the efficacy of foliar insecticide treatments that could be used for management. Cultivar evaluations comparing six and five commercial cultivars representing >46% of the sugarcane production area in Florida were conducted in 2017 and 2018, respectively. Fulmekiola serrata infestation levels did not differ among cultivars in 2017. However, infestation levels on CP 00-1101 were greater than on CP 96-1252 grown on organic soils, and infestation levels on CP 96-1252 were greater than on CPCL 97-2730 grown on mineral soils in 2018. Three insecticide evaluations, two in 2017 and one in 2018, were conducted. The pyrethroid lambda-cyhalothrin, which is registered for use on sugarcane, was consistently associated with the greatest decreases in F. serrata infestation levels. The neonicotinoids imidacloprid and thiamethoxam, as well as the butenolide flupyradifurone, decreased infestation levels but to a lesser extent than did lambda-cyhalothrin. The spinosyn spinetoram was associated with the lowest decreases in F. serrata infestation levels. Our results supported short-term F. serrata management recommendations: Popular Florida sugarcane cultivars should be considered equally susceptible to F. serrata until additional evaluations are conducted and F. serrata outbreaks can be treated with lambda-cyhalothrin when infestations stress the crop beyond acceptable levels.

The rice stink bug, Oebalus pugnax (F.), is a key pest of heading rice, Oryza sativa L. (Poales: Poaceae), in the southern United States. Sweep net sampling is the recommended method for sampling rice stink bug in rice, but there currently exists no specific recommendation for sweep length, and a large amount of variation likely exists amongst samplers. The objectives of this study were to determine the role that sweep length plays in sampling accuracy and determine the feasibility of using sweep lengths smaller than 180°. When monitoring sweep lengths by consultants, producers, and researchers, a large amount of variation in sweep length and a significant linear relationship between sweep length and rice stink bug catch per 10 sweeps was observed. Sweep length was then controlled at three levels (0.8, 1.8, and 3.5 m) and a change from 0.8 to 1.8 m in sweep length led to an increase on average of 2.28 rice stink bugs per 10 sweeps. These data suggest knowledge of sweep length is vital, and paired with large amounts of observed variation in sweep length, recommending a specific sweep length is ideal. Using Taylor's values, it was determined that 1.8 m sweeps resulted in density estimates that were as reliable as 3.5 m (180°) sweeps, suggesting a longer sweep length was not necessary. A 1.8 m sweep length recommendation would create an easier sampling regimen that is still reliable, which could lead to more accurate action threshold decisions being made for rice stink bug if it increases adoption in consultants and producers.

The invasive sugarcane aphid, Melanaphis sacchari (Zehntner), is a devastating new pest of grain sorghum. Studies were conducted utilizing an integrated approach of four management tactics: planting date, insecticidal seed treatment, a foliar-applied insecticide, and plant resistance. Experiments were conducted in 2016 and 2017 at Griffin, Tifton, and Plains Georgia, and in 2016 in Texas, Alabama, and Oklahoma, United States. Early planting was effective in reducing damage and increasing yields when compared to the late planting. Use of a resistant variety reduced cumulative aphid-days, plant injury and usually prevented significant yield loss. Foliar application of flupyradifurone when aphids reached an economic threshold, was an effective management tactic preventing aphid injury and yield loss. Use of clothianidin seed treatment also reduced aphid injury and yield loss of the susceptible hybrid but generally did not prevent injury and yield loss of the resistant hybrid. We conclude that an earlier planting date coupled with a resistant variety and judicious use of an efficacious foliar-applied insecticide can effectively manage sugarcane aphid on grain sorghum. An insecticide seed treatment also may be useful to reduce the risk of sugarcane aphid damage to seedlings of susceptible hybrids.

The sugarcane aphid, Melanaphis sacchari (Zehntner) (Hemiptera: Aphididae), has become a major pest of grain sorghum, Sorghum bicolor (L.) Moench, in the United States in recent years. Feeding by large densities of sugarcane aphids causes severe damage, which can lead to a total loss of yield in extreme cases. Our objective was to determine the effect of grain sorghum planting date on sugarcane aphid population dynamics and their potential to reduce yields. We conducted field experiments from 2015 to 2017 in which an aphid-susceptible grain sorghum hybrid was planted at four different dates, which encompassed the typical range of planting dates used in Arkansas production systems. Plots were either protected from sugarcane aphid feeding using foliar insecticide sprays, or left untreated to allow natural populations of sugarcane aphids to colonize and reproduce freely. Planting date impacted both the magnitude and severity of sugarcane aphid infestations, with the highest population densities (and subsequent reductions in sorghum yield) generally occurring on plots that were planted in May or June. Sugarcane aphid feeding reduced yields in the untreated plots in two of the four planting date categories we tested. Earlier planting generally resulted in less sugarcane aphid damage and improved yields compared with later planting dates. While the effect of planting date on sugarcane aphid populations is likely to vary by region, sorghum producers should consider grain sorghum planting date as a potential cultural tactic to reduce the impact of sugarcane aphid.

The northern corn rootworm, Diabrotica barberi Smith & Lawrence (Coleoptera: Chrysomelidae), is one of the most important insect pests in the U.S. Corn Belt. Efforts to obtain eggs from wild northern corn rootworm populations using techniques developed for other rootworm species have been unsuccessful due to lack of oviposition. In 2016, we evaluated four oviposition media in choice tests within each of three female densities in 30.5 × 30.5 × 30.5 cm BugDorm cages. The number of eggs laid per female was significantly affected by female density and the interaction of female density × oviposition media, but oviposition was relatively poor in all oviposition media (1.2 eggs per female when averaging the three female densities and all oviposition media). Single females were also evaluated in nonchoice assays in 6 cm × 6 cm × 8 cm clear plastic boxes and averaged up to 108 eggs per female depending on the oviposition media. In 2017, the cumulative number of eggs laid per female in boxes with one female was not significantly different from the number of eggs laid per female in boxes with 3 females. In 2018, the cumulative number of eggs laid per female was not significantly different between female densities of 1, 3, 5, or 10 females per box. Total egg production per box therefore increased as female density increased. More than 27,000 wild northern corn rootworm eggs were collected from just 190 females when collected relatively early in the field season. We now have an efficient and robust system for obtaining eggs from wild northern corn rootworm females.

Eucryptorrhynchus scrobiculatus (Coleoptera:Curculionidae) is an important pest in China that specifically damages Ailanthus altissima (Mill.) Swingle (Sapindales: Simaroubaceae). Trembler grid lamps and food attractant traps frequently were used to monitor and control E. scrobiculatus; however, the effect of these methods is poor in actual application. The purpose of this study was to develop a new monitoring method. Traps of seven colors and two shapes were compared with respect to the attraction of E. scrobiculatus adults, and a field trapping test was performed. We found that E. scrobiculatus adults were most sensitive to red (16.11 ± 7.72) and black traps (14.44 ± 8.07) and to tall vertical black shapes in the laboratory. In the field, red (70.50 ± 5.74) and black traps (60.75 ± 8.22) were most effective at catching E. scrobiculatus, and traps with color and attractant still were more attractive to E. scrobiculatus than traps with colors only. These results provide a reference for monitoring E. scrobiculatus adults.

The emerald ash borer (EAB) Agrilus planipennis (Fairmaire, Coleoptera: Buprestidae) will have untold impacts on the contributions hardwood timber products provide Louisiana's economy. We modeled a scenario where ash mortality was assumed to follow a PERT-Beta distribution to kill essentially all Louisiana ash within 25 yr. Future ash mortality volumes were discounted to the present and valued using market prices to estimate a present effect on timber receipts. Assuming the dead timber would have otherwise been typical trees of average quality, stumpage was presently valued at US$1.57 million, with deliveries totaling US$3.48 million. A salvage arrangement using the double declining balance method coupled with a second PERT-Beta distribution centered upon Louisiana's current 2.84% harvest-to-inventory proportion depreciated the timber's value monthly over 1 yr. Following salvage, average stumpage revenue declined -US$1.54 million, mill deliveries fell -US$3.41 million, whereas state timber severance tax collections declined by -US$46,800.The value added and employment direct effects to Louisiana's economy averaged -US$882,400 and -41.6 jobs, respectively.The multiplier effects of these losses emanating from the timber industry resulted in additional declines averaging -US$2.56 million in value added and -45.6 jobs across the state economy on the drop in output of -US$4.51 million. The total economic effects summed to -US$3.44 million in value added and -87.1 jobs on output declines of -US$9.46 million.

The pine processionary moth, Thaumetopoea pityocampa (Denis and Schiffermüller), is an important insect in the Mediterranean region, as it defoliates pines and its urticating hairs can cause allergic reactions in humans and animals. Moreover, this species exhibits an interesting genetic structure as recently a distinct East-North African mtDNA lineage (‘ENA clade’) has been described.This clade has been recently detected in Greek populations where it has currently expanded its range by replacing the ‘endemic’ T. pityocampa lineages. Here, we report new data on the rapid spread of ‘ENA clade’ in the Greek island Evoia in only a few years. As the underlying mechanisms of the ‘ENA clade’ range expansion has not been studied so far, we screened T. pityocampa for an infection with the heritable bacterial endosymbionts Wolbachia (Bacteria: Anaplasmataceae), Cardinium (Bacteria: Bacteroidaceae), Rickettsia (Bacteria: Rickettsiaceae) and Spiroplasma (Bacteria: Spiroplasmataceae). These bacteria can manipulate the reproduction of infected hosts, something that could potentially explain the rapid spread of ‘ENA clade’ lineage. Therefore, we screened 28 individuals that exhibited T. pityocampa ‘ENA clade’ and ‘endemic’ T. pityocampa haplotypes from nine populations scattered all over Greece. None of them was infected with any of the four endosymbionts, suggesting that these bacteria do not cause reproductive manipulations in T. pityocampa lineages and, thus, other factors should be explored in future research efforts.

Several domesticated Citrus species are grown as major commercial crops in California. Despite this, farmers currently use a single set of management practices, originally created for sweet oranges (Citrus sinensis (L.) Osbeck [Sapindales: Rutaceae]), for both sweet oranges and all mandarin species. Mandarins, primarily Citrus reticulata Blanco, Citrus clementina hort. ex Tanaka, and Citrus unshiu Marcovitch, comprise almost 25% of California citrus acreage, and little work has been done to assess host–pest interactions for these species. Citrus thrips (Scirtothripscitri Moulton [Thysanoptera: Thripidae]) are one of the main pests in California citrus and are major targets for early spring, “petal fall” insecticide applications. We used mixed species citrus blocks to test the influence of Citrus species, including C. sinensis, C. reticulata, C. clementina, and C. unshiu, on 1) citrus thrips densities following petal fall; 2) citrus thrips-induced scarring on both the calyx and stylar ends of fruit; and 3) fruit deformation. Citrus sinensis and C. unshiu had relatively high citrus thrips densities and scarring levels, whereas C. reticulata had lower densities of citrus thrips and scarring levels. The age structure of citrus thrips populations also varied across Citrus species. Fruit deformity associated with citrus thrips scarring was found on all Citrus species examined. Scarring on the stylar-end of fruit, a previously largely ignored location of citrus thrips scarring, was found to be common in C. reticulata. It is clear from our work that species-specific management guidelines for citrus thrips are needed in sweet oranges and mandarins.

Studying the spatial dynamics of pests allows the determination of abiotic and biotic factors affecting time and locations of pest attack to the crops. Such abiotic and biotic factors mainly include 1) climatic elements, 2) natural enemies, 3) phenological stage of plants, and 4) surrounding vegetation. Melon (Cucumis melo L. [Cucurbitales: Cucurbitaceae]) is among the most consumed fruit in the world, and the whitefly Bemisia tabaci (Gennadius) is among the main pests of this crop. This work aimed to determine the effects of surrounding vegetation, natural enemies, climatic elements, and stages of plants on the spatial dynamics of B. tabaci in commercial melon fields. Adult whitefly densities were monitored on four melon fields in a tropical climate region. Sampling location in crops was georeferenced. Experimental data were submitted to geostatistical analysis. The highest densities of B. tabaci occurred during hot periods experiencing lower rainfall, and when the surrounding area presented crops hosting B. tabaci, especially other melon farms. The density ratio of the predators (i.e., spiders and Geocoris sp.) were dependent on pest density. The pattern of field colonization by B. tabaci varies according to its density. Therefore, the surrounding vegetation, air temperature, and predators influence the spatial distribution of B. tabaci in melon fields. These results provide important information to melon farmers, assisting them to improve the management of B. tabaci in the field.

Ceratitis capitata (Wiedemann, 1824) is a significant insect pest of fruits produced worldwide and is capable of causing direct and indirect damage to fruit. Chemical control is the most frequently used management strategy, mainly involving organophosphate insecticides. However, the frequent use of this chemical group has resulted in unacceptable chemical residues on fruits. In this study, the toxicity of 18 insecticides was evaluated in adults and larvae of C. capitata in a laboratory. The organophosphate insecticides chlorpyrifos (Lorsban 480BR), phosmet (Imidan 500WP), and malathion (Malathion 1000EC); the spinosyns spinetoram (Delegate 250WG) and spinosad (Tracer); and the pyrethroid alpha-cypermethrin (Fastac 100SC) caused high mortality (>80%) in C. capitata adults in topical application bioassays and by ingestion when mixed with Biofruit 5% food lures. However, the insecticides chlorfenapyr (Pirate), spinetoram and chlorpyrifos produced a significant reduction in larval infestation of the fruits (67, 74, and 84% larval mortality, respectively). Insecticides based on spinosyns, alpha-cypermethrin, and cyantraniliprole are alternatives that can replace organophosphates in the management of C. capitata in the field.

Tomato yellow leaf curl virus (TYLCV), a begomovirus (genus Begomovirus) is the causal agent of tomato yellow leaf curl disease (TYLCD), which causes severe damage to tomato (Solanum lycopersicum) crops throughout tropical and subtropical regions of the world. TYLCV is transmitted by the whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) in a circulative and persistent manner. Our previous studies showed that tomato flavonoids deter B. tabaci oviposition, but the effects of tomato flavonoids on the settling and feeding behavior of B. tabaci and on its transmission of TYLCV are unknown. Using two near-isogenic tomato lines that differ greatly in flavonoid levels, we found that high flavonoid production in tomato deterred the landing and settling of B. tabaci. Moreover, electrical penetration graph studies indicated that high flavonoid levels in tomato reduced B. tabaci probing and phloem-feeding efficiency. As a consequence, high flavonoid levels in tomato reduced the primary and secondary spread of TYLCV. The results indicate that tomato flavonoids provide antixenosis resistance against B. tabaci and that the breeding of such resistance in new varieties could enhance TYLCD management.

Following the arrival of Tuta absoluta Meyrick in the eastern African subregion in 2012, several studies have shown numerous ecological aspects of its invasion. We investigated the impact of T. absoluta on people's livelihoods across four counties of Kenya. Here, 200 farmers in the country were interviewed in person using semistructured questionnaires. In addition to livelihood surveys, T. absoluta distribution was mapped between 2016 and 2018 to determine its current distribution across four countries (Kenya, Sudan, Tanzania, and Uganda) in the subregion. Albeit a recent invader, T. absoluta is abundant and distributed throughout the subregion and is viewed as the worst invasive alien species of agriculturally sustainable livelihoods by tomato farmers. The arrival of T. absoluta in the subregion has resulted in livelihood losses and increased both the cost of tomato production and frequency of pesticide application. We recommend the implementation of biological control along, with other control measures in an integrated approach, against T. absoluta in the subregion, where its impact on sustainable livelihoods is serious and long-term control strategies are required to curb its detrimental effects.

The aim of this study was to investigate the effect of gamma irradiation on survivability (adult emergence, sex ratio, adult longevity), fecundity (eggs hatchability, number of eggs produced), and morphological differences in the size of the ovary and testes of unirradiated and irradiated adults of Oriental fruit fly [Bactrocera dorsalis (Hendel)]. A dose of 100 Gy was determined as the minimum needed for inhibitory effects against B. dorsalis that would not deter adult emergence, sex ratio (male:female), and adult longevity, with 82.6 ±7.02, 1:1.09, and 107 ± 24.5, respectively. Doses from 50 to 400 Gy range did not completely prevent the adult emergence; however, the emergence decreased by increasing the radiation dose. Adult survivability significantly decreased among all the treatment groups of B. dorsalis, except for the 50 Gy and unirradiated flies. At a dose of 50 Gy, fertile females showed a significant reduction in fecundity by not producing eggs after mating with the sterile males. Meanwhile, the number of eggs laid decreased with increasing dose and no fertile egg was hatched starting at 100 Gy of irradiation. Testes and ovaries of 20-d old flies irradiated as pupae were smaller than those of control flies. In this study, 100 Gy was concluded as the minimum effective dose for the disinfestation and sterilization of B. dorsalis puparia. Results represent new findings used as a basis for sterile insect technique and quarantine programs for managing B. dorsalis, particularly in Malaysia.

Bacillus thuringiensis (Berliner) has demonstrated potential use in insect pest management. We evaluated the toxicity and sublethal effects of formulations of toxic baits composed of bacterial isolates (Bt) B. thuringiensis var. oswaldo cruzi (Bto), B. thuringiensis var. israelensis (Bti), B. thuringiensis var. kurstaki (Btk), and B. circulars (Bc) in combination with three food attractants 50% grape juice, 7% sugar cane molasses, and 7% hydrolyzed protein on adults of Zaprionus indianus (Gupta, 1970), the main pest of fig fruit (Ficus carica) in Brazil. Likewise, we evaluated the toxicity on the parasitoids Trichopria anastrephae Lima, 1940 and Pachycrepoideus vindemmiae (Rondani, 1875) in ingestion bioassays. Adults of Z. indianus showed high susceptibility to Bacterial isolates. However, the Bto isolate (10¹³ CFU. ml^-1) caused adult mortality of 100%, in 72 h after exposure, with LT₅₀ values of ≈20 h. By using the lethal concentrations (LC₉₀) of the Bto isolate, estimated via the concentration–response curves with the food attractants, a significant reduction (40 to 50%) in the total fecundity and in the embryonic viability of eggs from females fed with the toxic baits was observed. The food attractants + Bto (80 × 10⁸ CFU. ml^-1) did not cause significant mortality of T. anastrephae and P. vindemmiae adults (mortality < 20%). The bacterial isolates Bti, Btk, Bc, and Bto are considered promising for the formulation of toxic baits, because, besides providing toxic effect on adults of Z. indianus, they showed no toxicity on T. anastrephae and P. vindemmiae adults.

An ‘attract-and-kill’ (AK) device was evaluated for suppression of adult Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), on residential citrus. The AK device, made from weather-resistant plasticized PVC, lured D. citri adults by simulating the color of citrus flush and killed them with beta-cyfluthrin. This study evaluated: 1) lethality of AK devices weathered up to 8 wk on residential citrus; 2) survival of psyllids caged with potted plants and AK devices; 3) psyllid suppression achieved by AK devices on individual dooryard trees. AK devices weathered for up to 8 wk remained lethal to psyllids. Greenhouse trials evaluated survival of adult psyllids caged for 4 d with orange jasmine plants that were: 1) treated with an (beta-cyfluthrin-infused) AK device; 2) treated with a blank (no insecticide) AK device; or 3) ‘untreated’ with no AK device. After 4 d, psyllid survival was on average 95% lower among adults exposed to plants with AK devices than adults exposed to untreated plants or plants with blank AK devices. Less than half of the adults exposed to plants with AK devices were alive after 1 d and nearly all were dead after 4 d. Deployment of 20 AK devices per tree provided significant psyllid suppression on infested lemon trees from winter to summer and reduced mean reproduction (cumulative eggs) by 91% and mean attack intensity (cumulative psyllid-days) of adults by 59% and nymphs by 53%. AK devices could be an effective control option for D. citri in urban areas.

Coffee berry borer, Hypothenemus hampei Ferrari (Coleoptera: Curculionidae: Scolytinae), is the most damaging insect pest of coffee worldwide. Old coffee berries (raisins) are widely acknowledged as coffee berry borer reservoirs, yet few studies have attempted to quantify coffee berry borer populations in raisins remaining on farms postharvest. We collected ground and tree raisins at six coffee farms on Hawai’i Island to assess raisin density, infestation, coffee berry borer abundance, and adult mortality in three areas of each farm: trees, driplines (ground below the tree foliage), and center aisles (ground between tree rows). We also assessed infestation of the new season's crop by conducting whole-tree counts of infested green berries. Mean raisin density was significantly higher in the dripline compared to the center aisle and trees (131 vs 17 raisins per m² and 12 raisins per tree, respectively). Raisin infestation was significantly higher in samples from trees (70%) relative to those from the dripline (22%) and center aisle (18%). Tree raisins had significantly higher coffee berry borer abundance compared to both areas of the ground (20 vs 3–5 coffee berry borer per raisin). Adult mortality was significantly higher on the ground (63–71%) compared to the trees (12%). We also observed a significant positive correlation between ground raisin density and infestation of the new season's crop. Across all farms, we estimated that 49.5% of the total coffee berry borer load was present in dripline raisins, 47.3% in tree raisins, and 3.2% in center aisle raisins. Our findings confirm the importance of whole-farm sanitation in coffee berry borer management by demonstrating the negative impact that poor postharvest control can have on the following season's crop.

Queensland fruit flies Bactrocera tryoni (‘Q-fly’) have long adult prereproductive development periods, which can present challenges for sterile insect technique (SIT) programs. Holding the sterile flies in release facilities is expensive for control programs. Alternatively, releases of sexually immature males can lead to substantial mortality of sterile males before they mature. Recent studies have reported effectiveness of dietary supplementation with a mosquito larvicide (NOMOZ) that contains S-methoprene, a juvenile hormone analogue, for accelerating sexual development of fertile Q-fly males. However, it is not known whether effects on sterile flies are comparable to effects on fertile flies, or whether effects of methoprene-containing larvicide are comparable to effects of analytical standard methoprene such has been used in most studies. Here we address both knowledge gaps, investigating the effects of analytical standard methoprene and NOMOZ mixed with food and provided for 48 h following emergence on sexual development and longevity of fertile and sterile Q-flies. Compared with controls, fertile and sterile male Q-flies that were provided diets supplemented with methoprene from either source exhibited substantially accelerated sexual development by 2–3 d and longer mating duration. Unlike males, females did not respond to methoprene treatment. Although fertile and sterile flies were generally similar in sexual development and response to methoprene treatment, sterile flies of both sexes tended to have shorter copula duration than fertile flies. Neither methoprene supplements nor sterilization affected longevity of flies. The present study confirms effectiveness of dietary methoprene supplements in accelerating sexual development of both fertile and sterile male (but not female) Q-flies, and also confirms that low-cost mosquito larvicides that contain methoprene can achieve effects similar to those for high-cost analytical grade methoprene as prerelease supplements for Q-fly SIT.

The invasive spotted-wing drosophila, Drosophila suzukii (Matsumura), is a major pest of soft-skinned fruits. Since its introduction into North America and Europe, significant progress has been made in understanding the volatile cues used by this fly during food, oviposition site, and mate finding. Despite this progress, commercially available lures are non-selective. Here, we tested two Hanseniaspora uvarum (Niehaus) yeast compounds (isoamyl acetate and isobutyl acetate) and a leaf compound β-cyclocitral alone and in combination with a blend of four fermentation compounds (‘Fermentation lure’: acetic acid, ethanol, methionol, and acetoin) to improve D. suzukii attraction and selectivity. In laboratory assays, males and females were attracted to all seven individual compounds, although in electrophysiological assays, their antennae exhibited a dose-dependent response to only four of these compounds. In two-choice cage studies, the Fermentation lure was more attractive to D. suzukii than water controls, whereas β-cyclocitral and the mixture of isoamyl acetate and isobutyl acetate were not attractive in this larger-cage study. Moreover, adding the two-component H. uvarum compound blend to the Fermentation lure reduced D. suzukii attraction to the Fermentation blend. When these experiments were repeated in blueberry, raspberry, blackberry, and cherry orchards across several states in the United States over 2 yr, similar outcomes were observed: β-cyclocitral or the mixture of the H. uvarum blend did not improve the attractiveness of the Fermentation lure or its selectivity. This study demonstrates that cues from different sources may interfere with each other and reduce D. suzukii attraction to otherwise attractive odor combinations.

Plants use a variety of mechanisms to defend against herbivore damage, each with different consequences for agricultural production. Crops relying on tolerance strategies may need different pest management approaches versus those relying on resistance strategies. Previous work suggested that densities of fork-tailed bush katydids (Scudderia furcata Brunner von Wattenwyl [Orthoptera:Tettigoniidae]) that generated substantial scarring on cultivars of sweet oranges (Citrus sinensis, (L.) Osbeck [Sapindales: Rutaceae]) produced only low levels of scarring on cultivars of Citrus reticulata Blanco mandarins. We used field experiments in representative cultivars of these species to test non-mutually exclusive hypotheses regarding the mechanisms underlying this observation: 1) katydids are averse to feeding on mandarin fruits, 2) damaged mandarin fruits preferentially abscise, 3) damaged mandarin fruit tissue recovers during development, and 4) katydid scars on mandarins have a different morphology that may result in misclassification. We found strong support for the first hypothesis, demonstrating that katydids reject opportunities to feed on C. reticulata fruit. Instead of chewing deep holes in the fruit, as was commonly observed for C. sinensis, the katydids only scratched the surface of the C. reticulata fruits.The hypotheses of preferential abscission of damaged fruits and of recovery of damaged tissue were not supported. The low incidence of damage to the mandarins prevented a comprehensive assessment of the scar morphology; however, at harvest, the superficial cuts in C. reticulata were not easily distinguishable from background damage. This indicates that in contrast to C. sinensis, C. reticulata has substantial natural resistance to fork-tailed bush katydids making them a non-pest in this crop.

Species identification in the genus Reticulitermes is often difficult because of ambiguous morphological characters. Challenges in Reticulitermes spp. recognition have also been encountered in East Asia, includingTaiwan. Because of unknown Reticulitermes taxa in Taiwan and the possible origin of alien Reticulitermes kanmonensisTakematsu in Japan and Korea, reexamining Reticulitermes fauna in Taiwan is imperative. To clarify the Reticulitermes fauna in Taiwan, this study applied two mitochondrial genes (cytochrome oxidase subunit II [COII] and 16S rDNA) and morphological characters for species delimitation. Reticulitermes specimens collected from 63 localities across the main and adjacent islands ofTaiwan were analyzed. Phylogenetic analyses, morphological comparisons, and ecological traits suggested the existence of three species inTaiwan: Reticulitermes flaviceps (Oshima), R. kanmonensis, and Reticulitermes leptomandibularis Hsia and Fan. Altitudinal distributions among the three Reticulitermes termites tended to differ: R. flaviceps adapted to low hills, but R. kanmonensis and R. leptomandibularis occurred in medium mountainous areas. The combined data, including haplotype diversities and distribution range, suggest that 1) R. flaviceps is an endemic species and only found in Taiwan; 2) R. kanmonensis and R. leptomandibularis are both native species in Taiwan and China; 3) Japanese R. kanmonensis populations originated from southern China and/or Taiwan and that Korean populations were possibly introduced from Japan.

As a social insect, termites have different castes and division of labor in a colony. Investigating the social behavior of subterranean termites is a challenge due to the cryptic nature and large colony size. Planar arenas are commonly used to study these termites under laboratory conditions, and have provided several advantages. However, there is no means to designate areas such as a royal chamber or central nest from foraging sites because reproductives can move freely across arenas. In this study, we examined the minimum passing size of different castes of Coptotermes formosanus Shiraki (Blattodea: Rhinotermitidae), in order to develop a reproductive excluder and correlated minimum passing size with head widths and heights. We found that workers and soldiers of C. formosanus were able to pass through a gap greater than or equal to 0.7 mm. Our results showed that there are significant differences in the head width and height based on castes and head height was more critical than head width to determine passing size. We further confirmed feasibilities of the reproductive excluders using incipient colonies of C. formosanus. Confining reproductives using the excluder in laboratory experiments will provide more chances to study the royal chamber and central nest independently of foraging sites.

Temperature preference of two invasive subterranean termites, Coptotermes gestroi (Wasmann) and Coptotermes formosanus Shiraki (Blattodea: Rhinotermitidae), and their hybrids were determined in a horizontal thermal gradient. The activity of workers of four mating combinations: ♀C. gestroi × ♂C. gestroi (C. gestroi), ♀C. formosanus × ♂C. formosanus (C. formosanus), ♀C. gestroi × ♂C. formosanus (Hybrid G), and ♀C. formosanus × ♂C. gestroi (Hybrid F), when placed on the temperature gradients were videotaped and analyzed to determine the mean temperature preference values (mTPV). The temperature ranges for active termites were 21.9–39.5°C for C. gestroi, 11.1–39.5°C for C. formosanus, 25.3–38.2°C for Hybrid G, and 24.9–39.3°C for Hybrid F. There was no significant difference in the mTPV of C. gestroi and both hybrid mating combinations. The mTPV of both Hybrid G and Hybrid F was significantly higher than the parental species C. formosanus. Our results indicate that hybrid populations of C. formosanus and C. gestroi might be more active in tropical than temperate regions, and if established in temperate regions, they will be more active in summer months when the mean temperature exceeds 25°C.

Recent studies suggest that resistance in Helicoverpa zea (Boddie) (Lepidoptera, Noctuidae) to Cry1A(b/c) and Cry2Ab2 toxins from the bacterium Bacillus thuringiensis Berliner (Bacillales: Bacillaceae) has increased and field efficacy is impacted in transgenic corn and cotton expressing these toxins. A third toxin, Vip3A, is available in pyramids expressing two or more Bt toxins in corn hybrids and cotton varieties, but uncertainty exists regarding deployment strategies. During a growing season, H. zea infests corn and cotton, and debate arises over use of Vip3A toxin in corn where H. zea is not an economic pest. We used a three-locus, spatially explicit simulation model to evaluate when using Vip3A in corn might hasten evolution of resistance to Vip3A, with implications in cotton where H. zea is a key pest. When using a conventional refuge in corn and initial resistance allele frequencies of Cry1A and Cry2A were 10%, transforming corn with Vip3A slowed resistance to these toxins and delayed resistance evolution to the three-toxin pyramid as a whole. When Cry resistance allele frequencies exceeded 30%, transforming corn with Vip3A hastened the evolution of resistance to the three-toxin pyramid in cotton. When using a seed blend refuge strategy, resistance was delayed longest when Vip3A was not incorporated into corn and used only in cotton. Simulations of conventional refuges were generally more durable than seed blends, even when 75% of the required refuge was not planted. Extended durability of conventional refuges compared to other models of resistance evolution are discussed as well as causes for unusual survivorship in seed blends.

Under ideal conditions, widely adopted transgenic crop pyramids producing two or more distinct insecticidal proteins from Bacillus thuringiensis (Bt) that kill the same pest can substantially delay evolution of resistance by pests. However, deviations from ideal conditions diminish the advantages of such pyramids. Here, we tested the hypothesis that changes in maturing cotton producing Cry1Ac and Cry2Ab affect evolution of resistance in Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), a pest with low inherent susceptibility to both toxins. In terminal leaves of field-grown Bt cotton, the concentration of both toxins was significantly higher for young, squaring plants than for old, fruiting plants. We used laboratory bioassays with plant material from field-grown cotton to test H. zea larvae from a strain selected for resistance to Cry1Ac in the laboratory, its more susceptible parent strain, and their F₁ progeny. On young Bt cotton, no individuals survived to pupation. On old Bt cotton, survival to pupation was significantly higher for the lab-selected strain and the F₁ progeny relative to the unselected parent strain, indicating dominant inheritance of resistance. Redundant killing, the extent to which insects resistant to one toxin are killed by another toxin in a pyramid, was complete on young Bt cotton, but not on old Bt cotton. No significant fitness costs associated with resistance were detected on young or old non-Bt cotton. Incorporation of empirical data into simulations indicates the observed increased selection for resistance on old Bt cotton could accelerate evolution of resistance to cotton producing Cry1Ac and Cry2Ab in H. zea.

The foraging gene (for) is associated with foraging and other associated behaviors in social insect species. Photoperiod is known to entrain the rhythmic biological functions of ants; however, how photoperiod might influence the intensity and duration of foraging, and the expression of for, remains unexplored. This study determined the correlation between rhythm in foraging behavior and expression of the foraging gene (Sifor) mRNA in red imported fire ant, Solenopsis invicta Buren. Foragers were exposed to three photoperiod conditions (12:12 [L:D], 24:0 [L:D], and 0:24 [L:D]) in the laboratory and foraging activities were recorded using a video-computer recording system. Sifor expression in the foragers was tested using real-time reverse-transcription quantitative PCR. Results revealed that foraging activity rhythm and Sifor expression profile were unimodal under all three photoperiod conditions. Levels of foraging activity were associated with photoperiodic modification, a stable phase difference between the onset of activity and the onset of gene expression was discovered. Light-dark transients stimulated foraging activity in 12:12 (L:D). There were significant daily oscillations (amplitude of 0.21 ± 0.08 for 12:12 [L:D], 0.12 ± 0.02 for 24:0 [L:D], and 0.09 ± 0.01 for 0:24 [L:D]) in the expression of Sifor. A positive relationship (r = 0.5903, P < 0.01) was found between the expression level of Sifor and foraging activity, which indicated that Sifor is linked to some extent to foraging behavior. Our results demonstrated that foragers could adjust the rhythms in foraging behavior according to light–dark cycle and suggested that Sifor may play an important role in the response of S. invicta to photoperiod.

Cylas formicarius F. and Euscepes batatae Waterhouse are the most damaging sweet potato insect pests globally. Both weevils are thought to have invaded the Pacific alongside the movement of sweet potato (Ipomoea batatas (L.) Lam. Convolvulaceae), with C. formicarius having originated in India and E. batatae in Central or South America. Here we compare the genetic relationships between populations of the pests, primarily in the Asia-Pacific, to understand better their contemporary population structure and their historical movement relative to that of sweet potato. Cylas formicarius has divergent mitochondrial lineages that indicate a more complex biogeographic and invasive history than is presently assumed for this insect, suggesting it was widespread across the Asia-Pacific before the arrival of sweet potato. Cylas formicarius must have originally fed on Ipomoea species other than I. batatas but the identity of these species is presently unknown. Cylas formicarius was formerly designated as three species or subspecies and the genetic data presented here suggests that these designations should be reinvestigated. Euscepes batatae has very low genetic diversity which is consistent with its historical association with sweet potato and a recent introduction to the Asia-Pacific from the Americas. The distribution of E. batatae may be narrower than that of C. formicarius in the Asia-Pacific because it has relied relatively more on human-assisted movement. Consequently, E. batatae may become more widespread in the future. Investigating the invasion history of both species will help to understand the probability and nature of future invasions.

The citrus leaf beetle, Clitea metallica, is a specialized citrus pest through feeding on fresh leaves by larva and adults, and causes nicks and holes into leaves, leaving only a waxy surface layer. Insect cuticle is a complex exoskeleton that is not only involved in development but also protects the insect from environmental contaminations. Due to these key roles of the cuticle, cuticle-related genes are currently investigated in understanding the insect physiology in adaptation. Therefore, in this study, we built two libraries, transcriptomic (43 million clean reads) and small RNA (17 million clean reads), of C. metallica to identify cuticle-related genes and possibly associated miRNAs, being as an example to explore these data sets. Our results showed that a total of 47 cuticular protein genes were identified and most of these genes harbored a conserved motif (the Rebers and Riddiford motif) and belonged to the CPR family. Unigenes encoding proteins involved in chitin synthesis and degradation were also identified, including chitin synthase (2 unigenes), chitinase (14 unigenes), chitinase-like protein (2 unigenes), and chitin deacetylase (5 unigenes). Based on the small RNA library, we identified 30 miRNAs conserved across insect species. Among these miRNAs, 14 were predicted to be target genes associated with cuticle synthesis and degradation. In summary, 70 cuticle-related genes and 14 cuticle-related miRNAs were identified based on the transcriptome and small RNA library of C. metallica. These data sets will promote the understanding of cuticle molecular regulation in C. metallica as well as provide new potential targets for pest control.

Striacosta albicosta (Smith) is a maize pest that has recently expanded its geographical range into the eastern United States and southeastern Canada. Aerial application of pyrethroids, such as bifenthrin, has been a major practice adopted to manage this pest. Reports of field failure of pyrethroids have increased since 2013. Striacosta albicosta populations were collected in 2016 and 2017 from maize fields in Nebraska, Kansas, and Canada and screened with bifenthrin active ingredient in larval contact dose-response bioassays. Resistance ratios estimated were generally low in 2016 (1.04- to 1.32-fold) with the highest LC₅₀ in North Platte, NE (66.10 ng/cm²) and lowest in Scottsbluff, NE (50.10 ng/cm²). In 2017, O'Neill, NE showed the highest LC₅₀ (100.66 ng/cm²) and Delhi, Canada exhibited the lowest (6.33 ng/cm²), resulting in a resistance ratio variation of 6.02- to 15.90-fold. Implications of bifenthrin resistance levels were further investigated by aerial application simulations. Experiments were conducted with a spray chamber where representative S. albicosta populations were exposed to labeled rates of a commercial bifenthrin formulation. Experiments resulted in 100% mortality for all populations, instars, insecticide rates, and carrier volumes, suggesting that levels of resistance estimated for bifenthrin active ingredient did not seem to impact the efficacy of the correspondent commercial product under controlled conditions. Results obtained from this research indicate that control failures reported in Nebraska could be associated with factors other than insecticide resistance, such as issues with the application technique, environmental conditions during and/or after application, or the insect's natural behavior. Data generated will assist future S. albicosta resistance management programs.

There has been considerable interest in understanding biological, ecological, historical, and evolutionary processes that contribute to the diversification of species and populations among tephritid fruit flies. Only a limited number of studies have examined the genetic diversity and population biology of species belonging to the genus Anastrepha considering fine-scale differentiations associated to locality as well as hosts over an entire fruiting season.To expand our understanding of population structure and genetic diversity in one of the critical Anastrepha fruit flies populations in a highly diverse tropical environment we analyzed Anastrepha obliqua (Macquart) (Diptera: Tephritidae) in the Mexican state of Veracruz from five host fruit species and 52 geographic collections using sequence data from mtDNA and microsatellite markers from nuclear DNA. Indeed, we examined the population structure of this pest in a micro-geographic region and report on relationships and historical processes for individuals collected within a small portion of the geographic range of its distribution. Analyses of 1055 bp mtDNA sequences from CO1and ND1genes across 400 individuals detected 34 haplotypes. Haplotype and nucleotide diversity was low, with 53% of the individuals exhibiting a single haplotype (OBV1). Host association and fine-scale differentiation at 17 microsatellite markers across 719 individuals from 32 of the 52 geographic collections reveal fragmented A. obliqua populations. These findings have important implications for the implementation of the Sterile Insect Technique (SIT) and other pest management programs used to control this pestiferous fruit fly.

Conopomorpha sinensis Bradley is the dominant borer pest of litchi and longan in the Asian-pacific area. Reduction or interference of reproduction and mating of adult moths is one of the most used strategies to control C. sinensis. Insect reproduction is a critical biological process closely related to endocrine control. Conopomorpha sinensis genome and transcriptome information is limited, hampering both our understanding of the molecular mechanisms underlying hormone activity and reproduction and the development of control strategies for this borer pest. To explore the sex differences in gene expression profiles influencing these biological processes, de novo transcriptomes were assembled from female and male adult C. sinensis specimens. This analysis yielded 184,422 unigenes with an average length of 903 bp and 405,961 transcripts after sequencing and assembly. About 45.06, 22.41, 19.53, 34.05, 35.82, 36.42, and 19.85% of the unigenes had significant matches in seven public databases. Subsequently, gene ontology (GO) and kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis revealed comprehensive information about the function of each gene and identified enriched categories and pathways that were associated with the 2,890 female-biased genes and 2,964 male-biased genes. In addition, we identified some important unigenes related to hormone activity and reproduction among the sex-differentially expressed genes (DEGs), including unigenes coding for ecdysone-induced protein 78C, juvenile hormone (JH)-regulated gene fatty acyl-CoA reductase, vitellogenin, etc. Our findings provide a more comprehensive portrait of the sex differences involved in the relationship of two important physiological features—hormone activity and reproduction in C. sinensis and members of the family Gracillariidae.

Quarantine pests in plants can be a serious agricultural problem; many eradication programs using area-wide control measures have been implemented worldwide to combat this threat. Surveillance measures using sex pheromone (in general, male-attractant) traps are also widely implemented for rapid control and eradication of invasive pests. If initial pest colonization can be determined based on temporal count data of trapped insects (i.e., males), and countermeasures are applied only during colonization, costs incurred by these countermeasures would be dramatically reduced, especially in areas with frequent invasions. In this study, we developed a system to detect initial pest colonization, and to narrow down colonized regions using estimated temporal count data of the sweet potato weevil, Cylas formicarius Fabricius (Coleoptera: Curculionidae), in Tsuken Island, Okinawa, Japan. We verified the system by comparing our estimates to actual colonization data obtained via regular host plant surveys. Results indicated that our system was able to successfully detect pest colonization and estimate colonized regions. In this study, we discuss the conditions (i.e., pest biology, environment, etc.) that are optimal for application of our system.

Tribolium castaneum (Herbst) ranks as one of the most prevalent insects in food processing and storage facilities worldwide. Heat treatment has been revisited to disinfest food processing and storage facilities due to increasingly strict regulation on chemicals. The effect of acclimation of T. castaneum larvae to sublethal high temperatures of 36 and 42°C for 10 h on their heat adaptation was investigated, and transcript-level analysis combinating with real-time PCR (RT–qPCR) was applied for elucidating the heat adaptation mechanism of T. castaneum larvae. Short-term sublethal high temperature acclimation could greatly enhance the thermal adaptability in T. castaneum larvae. In total, 575, 875, and 1017 differentially expressed genes (DEGs) were, respectively, determined in comparisons between the 28 and 36°C treatments, the 28 and 42°C treatments, and the 36 and 42°C treatments. Fifty-three and 96 genes were commonly up- and down-regulated in both the 36 and 42°C treatments relative to 28°C, respectively. The results of RT-qPCR analysis further confirmed the RNA-seq analysis. The current results are in favor of enhancing the insecticidal effectiveness of extreme high temperature treatment and elucidating the heat adaptation mechanism in T. castaneum larvae.

The spotted lanternfly, Lycorma delicatula (White), is an introduced plant hopper that causes significant damage to host plants in the United States. Because of its affinity for tree of heaven, Ailanthus altissima (Mill.) (Sapindales: Simaroubaceae), control efforts have focused on the use of the systemic insecticide, dinotefuran, in designated trap trees. There is concern about exposure to this pesticide by non-target species, especially honey bees, Apis mellifera L., via lanternfly honeydew. Therefore, honey bee colonies were established in areas of high densities of trap trees and samples of honey, bees, and beeswax were collected in May, July, and October of 2017 for analysis. Samples were extracted by the QuEChERS method and analyzed using high-performance liquid chromatography with tandem mass spectrometry to determine the presence and quantity of dinotefuran. Additionally, honeydew from lanternflies was analyzed for dinotefuran and informal observations of trap tree visitors were made. None of the worker bee, wax, or honey samples indicated detectable levels of dinotefuran; however, honeydew samples collected did contain dinotefuran above the detection limit with amounts ranging from 3 to 100 ng per sample. The lack of dinotefuran in honey bee products matches the general absence of honey bees at trap trees in informal observations.

Anastrepha ludens (Loew) is one of the most important pests of citrus and mango crops in Mexico. A method used to control this pest is the sterile insect technique, which consists in the mass production, irradiation, and release of insects in affected areas. The production of insects begins with the establishment of colonies to produce eggs, which must be highly fertile to ensure an adequate production of larvae. However, female fecundity and fertility can be affected by adult density and sex ratio, thus an optimal sex ratio in mass-rearing cages must be used. The genetic sexing strain of A. ludens (Tapachula-7) allows the identification of the sex at the pupal stage, making it possible to establish rearing cages with different sex ratios. We determined if different sex ratios have an effect on egg production. Two sex ratios (4: 1 and 1: 1) were compared. Fecundity, fertility and survival at different ages were also determined. Higher fertility and fecundity per female were observed at a ratio of 4:1. However, females with higher fecundity had reduced survival probabilities. In conclusion, maintaining colonies with a lower proportion of males in cages ensures a greater fecundity and fertility. Further research is necessary to understand whether results can be attributed to lower male harassment in cages.

Biological invasions are a global threat to agricultural crops worldwide. In the Neotropical region, the spotted-wing Drosophila [Drosophila suzukii (Matsumura)] has rapidly expanded its geographical range spreading throughout South America in recent years. Besides climatic factors, the remarkable success of its establishment and subsequent distribution in this region is closely dependent on the diversity and availability of host plants. We evaluated the host potential (e.g., as food and oviposition sources) of fruits of jabuticaba [Plinia cauliflora (Mart.) Kausel (Myrtales: Myrtaceae)], Barbados cherry (Malpighia emarginata DC) (Malpighiales: Malpighiaceae), bonnet pepper (Capsicum chinense Jacq.) (Solanales : Solanaceae), and coffee (Coffea arabica L.) (Gentianales : Rubiaceae) and their effects on the biological and physiological traits of D. suzukii. For the fruit types where fly emergence occurred, we assessed the biological and physiological performance of the flies and compared these parameters with those recorded for flies reared on strawberries (Fragaria × ananassa Duchesne) (Rosales : Rosaceae) and an artificial diet. Our results revealed that oviposition into fruits and completion of the life cycle occurred on Barbados cherries only. Furthermore, field surveys revealed a higher emergence rate of D. suzukii on undamaged ripe Barbados cherries than damaged ones. Moreover, flies developing on Barbados cherries and an artificial diet presented earlier emergence, shorter developmental time, lower number of adults per female, and a female-biased sex ratio compared to flies developing on strawberries. Overall, our findings demonstrated suitability of Barbados cherry as a host for D. suzukii, which renders management of D. suzukii in Neotropical region an even more challenging task.

In 2009, a new pest of cassava crops was observed in the Federal District (Brazil) and identified as Eubulus (Kirsch) sp. (Coleoptera: Curculionidae). The pest is currently distributed in the states of Goiás, Minas Gerais, Mato Grosso do Sul, and Paraná. The larvae consume roots, causing the tissue to rot and making it unfit for consumption. The damage can extend to 100% of the roots. Owing to the potential losses that this pest is capable of causing, studies are needed on its biology, ecology, and future management strategies aimed at minimizing the losses, allowing the continuity of cassava cultivation in Brazil. This study reports on the occurrence of the pest in Brazilian Cerrado, its distribution in Brazil, the symptoms of its infestation and estimates the damage caused.

Codling moth, Cydia pomonella (L.), is a significant pest of pome fruits and walnuts worldwide. Recently, a three-chemical kairomonal lure, comprised of pear ester, acetic acid, and n-butyl sulfide, was successfully used as an attractant in a mass-trapping scheme to reduce fruit damage in commercial apple orchards. In this study, we tested whether this same attractant could be used outside of an orchard setting to decrease fruit damage in isolated, unmanaged apple (Malus spp.) (Rosales: Rosaceae) trees. Traps containing the lures were placed in trees before the first codling moth flight and maintained throughout the summer. We found that while the traps statistically reduced the percent of apples damaged near the trap, the effect was smaller than expected and limited to areas near the trap. It is currently unclear, but site-specific effects (e.g., host type, apple density, codling moth source) may be important factors in the efficacy of management tools in these systems. While kairomone-based trapping could be a practical and feasible management tool in individual trees outside of orchards, more work needs to be done to understand the limitations of this method.