Journal of Pest Science最新文献

Invasive ant species like Linepithema humile cause significant ecological and economic harm, making effective control strategies essential. Insecticide baits are currently the most effective approach for controlling ants. Therefore, quantifying how palatable or unpalatable baits, bait additives, or toxicants are, is critical for developing effective control methods. Recent research shows that when animals can compare a test food containing a bitterant with another option, they are much better at detecting the bitterant and thus rejecting the test food. Here, we deploy a newly developed comparative evaluation methodology to examine the palatability to L. humile workers of three toxicants commonly used in invasive ant control: fipronil, spinosad, and imidacloprid. Additionally, we tested egg-white protein in sucrose solutions to assess its impact on bait acceptance. Ants showed no significant preference between pure sucrose and sucrose-toxicant solutions, indicating that they either cannot detect the toxicants or do not find them distasteful. Survival tests confirmed that the toxicant concentrations used, fipronil at 0.0001% and 0.001%, spinosad at 0.015% and 0.15%, and imidacloprid at 0.005%, were lethal, with a survival rate of 50% or below after 72 h. However, ants found egg protein additive unpalatable, significantly preferring pure sucrose to a sucrose egg-white protein mix. These findings confirm that three major toxicants are suitable for use in baits, and that reported abandonment or avoidance of toxic baits is not due to the unpalatability of these toxicants. However, the addition of egg protein alone to sucrose baits, even at ratios which optimise colony growth, is likely counterproductive. Future research should investigate the relative preference of invasive ants for various bait matrixes over naturally available food, ensuring more effective pest management strategies.

Carpophilus truncatus (Murray), a nitidulid beetle, has become a major threat to almond industries globally. While there are existing mass trapping strategies for other Carpophilus species, an effective lure for this nut-attacking pest is urgently required. This study leverages our knowledge of the chemical ecology of Carpophilus, particularly its relationship with gut-associated yeasts, to develop a new semiochemical attractant for C. truncatus. Wickerhamomyces rabaulensis was identified as the predominant gut-associated yeast in field-collected C. truncatus. Field bioassays demonstrated that traps baited with live cultures of W. rabaulensis captured more beetles compared to those baited with Hanseniaspora guilliermondii, a yeast from stone fruit-attacking Carpophilus species. GC–MS analysis revealed both qualitative and quantitative differences in the odour profiles of the two yeasts. Seven volatile compounds were identified from headspace of W. rabaulensis and confirmed to be detected by C. truncatus antennae using GC-EAD. Choice-test bioassays showed adult C. truncatus preferred a synthetic blend based on W. rabaulensis volatiles over a commercial lure designed for stone fruit Carpophilus species. Field trials with various formulations of W. rabaulensis volatiles indicated that a modified commercial lure containing isoamyl acetate and isobutyl acetate was more attractive to C. truncatus and caught fewer non-target species such as C. hemipterus. This study demonstrates the potential of insect-yeast chemical ecology in developing effective semiochemical-based lures for monitoring and mass trapping C. truncatus in almond orchards.

In the rhizosphere ecosystem, the tomato develops associated with a diversity of microorganisms and/or organisms, many of which can be beneficial or pathogenic for this plant. Plant-parasitic nematodes (PPN) produce significant economic losses in tomato crops. Nacobbus sp. is one of the most frequent and abundant PPN in Argentina. Management of this nematode through biological strategies constitutes an eco-compatible alternative to ensure the sustainability of the horticultural system. In this work, the potential of the combined application of broccoli aqueous extract (BAE—12%) and Purpureocillium lilacinum SR14 (1 × 10⁶ conidia g⁻¹) for the control of N. aberrans s.l. in tomato (Solanum lycopersicum cv. Platense) plants were evaluated. The chamber test was conducted with sterile horticultural soil, artificially infested with J2, while naturally infested horticultural soil was employed for the greenhouse test. The antagonist activities of P. lilacinum SR14, BAE and SR14 + BAE against the N. aberrans s.l. population were evaluated in the two assays. Results showed that the combined treatment (P. lilacinum SR14 + BAE) significantly reduced the PPN population, both in chamber (22%) and greenhouse (98%) grown plants. Furthermore, it was demonstrated that both strategies were compatible with each other, the host crop and the soil microbiome. Therefore, this type of agroecological practice, could be a plausible alternative to be adopted by horticultural producers in Argentina for the control of the phytonematode, N. aberrans s.l.

Numerous phytosanitary threats challenge global agriculture, ecosystems, and food security. These threats are exacerbated by non-native species and diseases that are projected to intensify in the future due to global warming and anthropogenic habitat alterations. Assessments of the ecological impacts of overlooked phytosanitary threats are urgently needed under shifting environments. In this study, the potential effects of two non-native Orthoptera species (the house cricket Acheta domesticus and the two-spotted cricket Gryllus bimaculatus) were assessed using functional response analyses. We quantified their potential impacts on agriculturally relevant crops (millet) under increasing temperatures (20 °C, 25 °C, and 30 °C) as individuals and between interspecific pairs. The experiments revealed similar impacts on seeds between both species and across temperatures. Temperature tended to amplify consumption rates and functional responses. The combined interspecific cricket presence generally yielded an additive effect on seeds, with a few instances of synergistic interactions, whereby non-trophic interaction strengths significantly interacted with resource density and temperature. Both species demonstrated remarkable adaptability to varying temperatures, with low mortality accentuating their capacity for impacts under current and future temperatures. This emphasizes the imperative of including both species in phytosanitary assessments. Moreover, population monitoring and the implementation of effective management strategies emerge as pivotal measures for safeguarding agricultural productivity and conserving local ecosystems in the future. The study’s findings thus underscore the potential impact of A. domesticus and G. bimaculatus, particularly in the context of steadily ascending temperatures, to pose a risk to agricultural productivity and food security.

Insects and plants established long-lasting associations with microbes, whose role on insect–plant associations remains largely unknown. We hypothesized that both plant endophytes and insect symbionts benefit their hosts during insect–plant interactions. In the present study, we used the maize-Spodoptera frugiperda (JE Smith, 1797) (Lepidoptera: Noctuidae) system and five bacterial symbionts: a maize endophyte (Rhizobium larrymoorei IILzm-Idp03), two residents (Enterococcus spodopteracolus IIL-Sfm05 and E. entomosocium IILSfc-sus01) and one transient (Bacillus sp. IIL-Sfb05) gut bacteria of S. frugiperda. The ant-associated actinobacterium Streptomyces novaecaesareae IIL-ASP45 was also tested for not sharing any interactions with the maize-herbivore system studied. Bacteria associated with maize and/or S. frugiperda promoted plant growth depending on the inoculation strategy used. The tested bacteria colonized roots and leaves of plants regardless of their original host. Mortality and/or S. frugiperda larval efficiency of food utilization was affected in plants inoculated with IILSfc-sus01, IILSfb05, IILzm-Idp03 and IILASP45, but not with IILSfm05. The expression of selected maize-defensive genes and the volatile organic compounds (VOCs) profile was altered in all inoculated plants. Changes in VOCs did not affect adult S. frugiperda female preference for oviposition, but significantly affected the number of eggs laid/plant.

Semiochemical-baited traps are a key component of post-border surveillance for detection of non-native and potentially invasive bark and wood-boring beetles (Buprestidae, Cerambycidae, Curculionidae: Scolytinae) at risk of introduction in untreated woody materials used in global trade. Because the particular species that may arrive with imported goods is unknown, plant protection agencies need trapping protocols that effectively survey all three taxa. Baiting traps with host volatiles and aggregation/sex pheromones of longhorn beetles increases efficacy of detecting Cerambycidae and Scolytinae, but its effect on detection of Agrilus species and other jewel beetles is unknown. In this multi-country trapping study we found that the addition of ethanol and common aggregation/sex pheromones of longhorn beetles to green multi-funnel traps placed in the mid-upper forest canopy had negative effects on abundance of Agrilus species and other jewel beetles collected but no effect on their species richness, and significant positive effects on species richness and abundance of Cerambycidae and Scolytinae. Baiting green canopy traps with longhorn beetle pheromones increased the efficacy of traps for detecting total target taxa of bark and wood-boring beetles at risk of international movement in untreated woody materials. This information is beneficial for the design of multi-taxa surveys, potentially saving money and resources without decreasing trapping efficacy.

Aedes aegypti, known for transmitting viruses such as dengue, Zika and yellow fever, poses a significant public health threat. Conventional insecticides give rise to a range of issues, including ecological contamination and insect resistance. Hence, there is a pressing demand for environmentally-friendly, safer and more efficacious strategies for mosquito control. With the rapid advancement of the CRISPR/Cas9 system in gene function exploration and pest population control, substantial progress has been achieved in utilizing CRISPR/Cas9-based gene drive systems across various mosquito species. Only a few studies on gene drive technology have been conducted in Ae. aegypti. In this study, we constructed two complete drives for Ae. aegypti with different Cas9 promoters, each targeting kmo. Our drive based on PubCas9 had limited activity, but one with ExuCas9 exhibited super-Mendelian inheritance rates of approximately 60%. We observed low but detectable somatic activity of the drive and no evidence of maternally deposited Cas9. Germline resistance allele formation rates were similar to drive conversion rates, but most wild-type alleles in the germline remained uncut. Injections into the ExuCas9 drive line had 100% knockout efficiency among surviving offspring at three separate target genes. These results support the development and application of novel genetic pest control technologies aimed at combating Ae. aegypti.

The rosy apple aphid is a major pest of apple orchards, it is also potentially ant tended. Attract&Reward strategy is a promising pest management method, combining semiochemicals as attractant and companion plants as food sources for natural enemies. However, this method is difficult to implement owing to complex multi-tropic interactions (including mutualist interactions) at play in agroecosystems. Using sentinel plants (apple seedlings bearing rosy apple aphid) we investigated individual and combined effect(s) of Attract&Reward components on aphid biocontrol in early and late spring in apple orchards. The attract component was implemented by adding apple seedlings treated with a plant defense stimulator (inducing plant semiochemicals attractive for natural enemies). The reward component was implemented by adding potted plants producing extrafloral nectar. Moreover, the impact of ant tending on aphids (in exchange of honeydew) was evaluated using exclusion device. We demonstrated that the Attract&Reward strategy enabled increasing aphid biocontrol (vs. control) but only when ants were excluded, and only in early spring. The exclusion device successfully excluded ants in early and late spring but not Araneae and Syrphidae. Araneae and Syrphidae were not affected by the individual Attract&Reward components or their combination. The combination of Attract&Reward components is an effective strategy but only when ants are excluded. This is among the few studies showing experimentally that presence of ants conditions the efficiency of biocontrol strategies, including those based on Attract&Reward concept. A better understanding of trophic and mutualistic interactions is required to design effective conservation biocontrol strategies.

The insect species Tenebrio molitor L. (Coleoptera: Tenebrionidae) is a stored-product pest which tend to infest a variety of durable agricultural commodities, mostly oriented toward cereals and related amylaceous substrates of low humidity. Thus, the past few years, research on T. molitor has been focused on its biology, ecology, and control methods due to its pest status. However, recently, the same insect species has undergone a significant reevaluation, as it is considered as a promising alternative protein source not only for animal feed but also for human consumption. The direction to new applications of T. molitor in sustainable agriculture and livestock farming has been mainly driven by the green light of the European Commission and European Food Safety Authority, which has redirected the interest of the scientific community toward utilization of T. molitor as a novel protein source. This shift is evidenced by a rapid increase in related publications since 2017. Recent publication of this sector highlights the nutritional benefits of T. molitor larvae, their potential in waste management, and the economic viability of its mass production. However, there is still a gap in the literature concerning the optimization its mass rearing, the disease management, and the exploration of the by-products produced through the rearing of T. molitor, i.e., soil fertilizer. This paper reviews the trajectory of T. molitor research, emphasizing its dual role as both a pest and a valuable resource.

Numerous arthropod pest species can cause significant losses in the quantity and quality of stored products. Currently, the most common pest control strategy is the use of a limited number of authorized synthetic insecticides. However, the overuse of these insecticides has led to an increase in pesticide resistance, reducing their effectiveness. Biological control using natural enemies offers an effective alternative to prevent insect populations from reaching pest status. Generalist predatory mites are noted for their potential as biocontrol agents as they can prey on a large variety of pest species and are easy to manage and apply. We evaluated the suitability of three predatory mites, Blattisocius tarsalis, Cheyletus malaccensis, and Amblyseius swirskii, for controlling several insect pests that are usually present in stored cereals. Prey acceptance and predation rates were assessed in experiments in which a known number of preys were offered to mite females in different arenas. Blattisocius tarsalis and C. malaccensis exhibited broad polyphagous behavior on insect pests commonly found in stored rice and other cereals. In contrast, A. swirskii was ineffective against these pest species. The efficacy of B. tarsalis and C. malaccensis, individually or in combination, in controlling populations of Oryzaephilus surinamensis and Sitotroga cerealella in medium-size arenas was also evaluated. Whether individually or in combination, both predatory mites reduced populations of O. surinamensis or of S. cerealella by half. These results suggest that periodic releases of these predatory mites could maintain these pest populations under control.