Journal of economic entomology最新文献

In the southern United States, thrips are a significant early season pest of cotton. In the United States, in 2022, 98% of cotton acres were infested with thrips, and, of those acres, 45% were treated for thrips. Thrips injury resulted in over $113 million dollars in losses plus control costs to the cotton industry in the United States that year. A new Bacillus thuringiensis trait known as ThryvOn has been commercialized to provide control against thrips. There is ongoing debate about the need for an insecticidal seed treatment to improve thrips control on ThryvOn varieties. Field studies were conducted to determine if the addition of an imidacloprid seed treatment improved efficacy against tobacco thrips and to determine if reduced rates of seed treatments (0, 25, 50, 75, and 100% of the labeled rate) provided benefits for thrips control in ThryvOn cotton. To control for infestation pressure, a complementary greenhouse study was conducted using the same treatments under controlled conditions. Imidacloprid provided only a limited benefit for improved management on ThryvOn cotton in the greenhouse study, but no benefit in the field study. Efforts in pest surveillance should be continued in ThryvOn cotton to allow for foliar applications when warranted based on established thresholds. No conclusions can be drawn about the benefits of an imidacloprid seed treatment for resistance management in ThryvOn cotton from this study, but these data suggest that any benefit would be minimal.

Thrips parvispinus (Karny) (Thysanoptera: Thripidae), an invasive thrips species, poses a significant threat to global agriculture due to its polyphagous nature and rapid spread. Its recent arrival in the continental United States raises concerns about potential impacts on ornamental and vegetable crops. Dip treatments might serve as a phytosanitary practice for growers to start with plants free of visible pests. This study aimed to assess the efficacy of dip treatments using 4 biorational and microbial insecticides (mineral oil and Beauveria bassiana-based) in controlling T. parvispinus on bean seedlings. Following gentle agitation of cuttings, artificially infested with 10 second-instar (L2) larvae, for 15 s in each solution, thrips infestation was evaluated at 1, and 24 h postdipping, scoring the numbers of dislodged and dead larvae. Additionally, we tested whether dipping could cause phytotoxicity on bean (Phaseolus vulgaris L.), gardenia (Gardenia jasminoides Ellis), and mandevilla (Mandevilla splendens (Hook.f.) Woodson) cuttings during a 7-day period. Our results demonstrated that dip treatments effectively dislodged and killed T. parvispinus L2 larvae from infested cuttings, with BotaniGard-ES and Suffoil-X exhibiting the highest efficacy and a dislodgment rate of 80%-100%. BotaniGard-ES was the only product causing phytotoxicity on bean seedlings, but not on mandevilla and gardenia. Overall, we demonstrated that dip treatment using biorational insecticides is an additional tool that can be incorporated in the integrated pest management of T. parvispinus. These results hold implications for the broader application in the management of thrips across various plants propagated from cuttings.

The citrus pest Cacopsylla citrisuga (Yang & Li), a vector for Citrus Huanglongbing (HLB), exhibits distinct sensitivity to temperature variations. This study utilized an age-stage, 2-sex life table to evaluate the development and reproduction of C. citrisuga across 5 temperatures (17, 20, 25, 28, and 31 °C). The findings indicate that Cacopsylla citrisuga can complete its life cycle within the range of 17-28 °C, with optimal temperature at 20 °C, where the highest survival and fecundity rates in females were observed. An increase in temperature correlates with a decrease in developmental duration for all stages, with the shortest at 28 °C. The net reproductive rate (R0) peaked at 20 °C, while the intrinsic rate of increase (r) and the finite rate of increase (λ) increased with the increase of temperature. Conversely, the average generation time (T) decreased with the increase of temperature, underscoring the pivotal role of temperature in population dynamics. The developmental threshold temperature and effective accumulated temperature were determined for each stage, furnishing crucial parameters for pest management strategies. This research highlights the importance of temperature in dictating the distribution and prevalence of C. citrisuga, offering valuable insights for the development of targeted control measures against this HLB vector.

German cockroaches (Blattella germanica (L.)) are a persistent pest in affordable housing and studies indicate that residents implement control on their own to deal with cockroaches within their homes. While many do-it-yourself (DIY) control options have proven ineffective, baits are widely considered to be a viable DIY solution for residents who do not have access to professional pest control services. To evaluate their efficacy, we tested consumer-use baits (Combat gel bait, Combat bait stations, and Hot Shot liquid bait stations) in both laboratory two-choice assays and in-home assays, comparing them with professional gel baits (Vendetta Nitro, Advion Evolution, and Maxforce FC Magnum). All baits (consumer- and professional-grade) caused > 80% mortality within 14 d in laboratory assays, including against home-collected German cockroach populations. However, the in-home efficacy of consumer-grade baits in comparison to their performance in laboratory assays was inconsistent, with some baits resulting in significant declines in trap catch in 1 month (Hot Shot liquid bait stations), some taking longer (Combat gel bait), and some never showing a decline (Combat bait stations). Discrepancies between product performance in laboratory and in-home studies are concerning and suggest that laboratory assays alone might not be indicative of the potential for control, especially in the context of the more complex home environment. Failures of consumer-grade baits may require re-evaluation of current recommendations for the use of consumer-grade cockroach baits as a viable control option for residents struggling with cockroach infestations without access to professional pest management.

Marmalada hoverfly, Episyrphus balteatus De Geer (Diptera: Syrphidae), is a cosmopolitan fly species providing pest control and pollination services. As wheat aphids cause significant losses to global wheat production, a systematic evaluation of the predatory potential and biocontrol service functions of E. balteatus in wheat ecosystems was undertaken. The daily maximum prey consumption of third instar E. balteatus on the adult of Rhopalosiphum padi Linnaeus, Schizaphis graminum Rondani, and Sitobion miscanthi Takahashi (Hemiptera: Aphididae) were 250, 500, and 100 individuals/third instar larvae, respectively. The S. graminum population decline rates in cages after release of the third instars at ratios of 1:100 and 1:200 were 100% and 94.17%, respectively, 72-h after exposure. Feeding assays involving R. padi, S. graminum, and S. miscanthi showed a DNA detectability half-life of 4.17, 6.44, and 4.83 h, respectively, in third instar larvae of E. balteatus. Using multiplex polymerase chain reaction-based gut content analysis to detect prey DNA remains, we confirmed that E. balteatus larvae preyed upon R. padi, S. graminum, S. miscanthi, and Metopolophium dirhodum Walker (Hemiptera: Aphididae) in the field experiments during 2022 to 2024. A significant positive correlation was also found between corrected prey detection rate and aphid population dynamics. These results provide an entry point for understanding the ecological service function of E. balteatus and developing the biological control strategy of the wheat aphid management.

The swede midge, Contarinia nasturtii Kieffer (Diptera:Cecidomyiidae), is a gall-forming insect pest that targets cruciferous plants. Since its introduction to North America in the early 2000s, the midge has expanded its range to include farming regions in Quebec and the Northeastern USA. In this study, we evaluated the susceptibility of 4 popular kale varieties-Green Curly-(Vates), Red Russian, Red Curly (RedBor), and Lacinato/Tuscan-to swede midge infestation in on-farm trials conducted over consecutive years. Our results indicate substantial variability in susceptibility among varieties, with Red Russian kale consistently exhibiting the highest damage incidence across both years. These findings provide valuable insights for developing effective integrated pest management (IPM) strategies tailored to organic and small-scale vegetable farming contexts, emphasizing the role of crop genetic resources in pest mitigation and sustainable agriculture. In addition, this study highlights the potential of non-chemical approaches for managing swede midge, leading to a more diverse and adaptable IPM toolbox for growers.

A sticky trap is a simple, low-cost method for the field estimation of insect population density. The present study was investigated the attraction of Stomoxys calcitrans using 5 different colors of sticky trap (blue, gray, transparent, white, and yellow). Throughout the sampling period, the sticky traps collected 1,559 S. calcitrans adults, of which 560 (36%) were females and 999 (64%) were males. The mean numbers of S. calcitrans on the 3 dairy cattle farms sampled differed significantly among the different trap colors, with both sexes being preferentially attracted to white or blue sticky traps. However, the white sticky traps were more effective at trapping S. calcitrans than the yellow and transparent sticky traps. Thus, a white-colored fly trap design was recommended for monitoring purposes.

The Anoplophora chinensis (Coleoptera: Cerambycidae) (Forster), a serious phytophagous pest threatening Castanea mollissima Blume and Castanea seguinii Dode, poses risks of ecological imbalance, significant economic loss, and increased management difficulties if not properly controlled. This study employs optimized MaxEnt models to analyze the potential distribution areas of A. chinensis and its host plants under current and future climate conditions, identifying their movement pathways and relative dynamics. Results indicate that all models achieved an average AUC value exceeding 0.86, demonstrating low complexity and high predictive accuracy. The key climatic variables influencing the geographic distribution of A. chinensis and its host plants include temperature and moisture-related bioclimatic variables such as mean diurnal range, minimum temp of coldest month, mean temp of wettest quarter, annual precipitation, precipitation of driest month, and precipitation seasonality. Under both current and future conditions, these 3 species are primarily distributed in the southwestern regions of China. Notably, the suitable growth area for all 3 species shows varying degrees of increase. Additionally, C. mollissima and C. seguinii exhibit a trend of eastward displacement in response to climate change. Overall, the findings provide significant practical value for the monitoring, early warning, and targeted control strategies for A. chinensis. Furthermore, these results offer a basis for timely conservation strategies to mitigate the potential impacts of climate change.

Methoxyfenozide is an insecticide with a unique mode of action on the insect ecdysone receptor and has been registered for the control of insect pests all over the world. In the present work, Spodoptera frugiperda was exposed to sublethal and lethal concentrations of methoxyfenozide to determine its impact on specific biological traits, metabolic enzyme activity, and the expression of detoxification enzymes. The result showed that 72-h posttreatment with LC50 and LC70 of methoxyfenozide significantly reduced the fecundity (eggs/female) of the F0 generation compared to those of the control group. However, the duration of the prepupal period was significantly increased. The exposure to LC10, LC30, LC50, and LC70 concentrations of methoxyfenozide significantly extended the developmental duration of larvae in F1 individuals. The fecundity of the F1 generation was significantly decreased, and the population life table parameters of F1 were also significantly affected. The activity of carboxylesterases showed little significant change, whereas the activity of glutathione S-transferases (GSTs) and cytochrome P450 monooxygenases (P450s) was significantly altered after exposure to LC10, LC30, LC50, and LC70 of methoxyfenozide. In total, 24-, 48-, and 96-h posttreatment with LC10, LC30, LC50, and LC70 of methoxyfenozide could cause upregulation of P450 genes such as CYP6AE44, CYP6B39, CYP9A26, CYP9A58, CYP9A59, and CYP9A60, as well as GST genes including GSTe3, GSTe9, GSTe10, GSTe15, GSTo2, GSTs1, GSTs5, GSTm2, and GSTm3. These findings could be instrumental in elucidating the molecular mechanisms underlying the sublethal and lethal effects of methoxyfenozide to S. frugiperda.

Industrial hemp, Cannabis sativa L., is an herbaceous annual plant that has recently re-entered crop production both in the field and in greenhouses within the United States. Like many agronomic crops, hemp production faces several insect pest challenges. Aphids pose a unique threat to hemp, being found in both indoor and outdoor production. Aphids affect hemp by reducing plant growth, bud production, concentrations of cannabinoids, and removing photosynthate. Additionally, aphids are vectors of plant viruses, and several species are known to transmit viruses to hemp. Limited research exists regarding the host suitability of hemp for common aphid pests in Louisiana. Thus, experiments were conducted to determine the life table statistics and feeding behaviors of Myzus persicae, Aphis gossypii, and Phorodon cannabis to determine the potential pest population dynamics of these pests on hemp. Hemp cv. Maverick was not a good host for either A. gossypii or M. persicae, resulting in negative intrinsic rates of increase and no sustained colonization. Although individuals of M. persicae and P. cannabis initiated probes at comparable rates, M. persicae probe durations were significantly shorter and probes were more frequent, indicating an absence of positive responses to probing hemp. A significant difference was observed in the percentage of individuals of A. gossypii initiating probes, and probe duration was significantly shorter than P. cannabis and significantly longer than M. persicae. Both A. gossypii and M. persicae spent significantly less time probing in phloem when compared with P. cannabis. These electrical penetration graph results indicate that A. gossypii and M. persicae do not find C. sativa cv. Maverick a suitable host; however, both species of aphids may still pose a threat to C. sativa production as virus vectors.