Entomologia Experimentalis et Applicata最新文献

Accurate identification of agricultural pests is a major component of integrated pest management. The seedcorn maggot, Delia platura (Meigen) (Diptera: Anthomyiidae), is a cosmopolitan polyphagous pest species that may be found in high numbers in numerous crops. Two morphologically identical genetic lines of D. platura (H and N) with distinct distributions were recently identified. To date, no study has investigated the reproductive compatibility of the two lines and thus the possibility that they may actually be two unique biological entities. A previous study described the reproductive traits of the two lines and suggested that H-line females are highly selective toward the male with which they mate, pointing to a possible pre-mating isolation mechanism between the lines. Using laboratory-reared colonies originating from the Montérégie region in Québec, Canada, this study investigates the reproductive compatibility of the two D. platura lines. We found that only one of 30 H-line females was inseminated by an N-line male, further suggesting mate choice as a pre-mating isolation mechanism between the lines. However, N-line females were readily inseminated by H-line males, suggesting a lack of pre-mating isolation in this type of cross. The eggs laid by N-line females mated with H-line males had a lower hatching rate than the ones laid by females of intraline crosses, suggesting either post-mating pre-zygotic or post-zygotic partial isolation. However, the larvae that did hatch had a comparable developmental success to those from intraline crosses in terms of survival and developmental time from larval hatching to adult emergence, pupal mass, and adult sex ratio, suggesting a lack of post-zygotic isolation for these life stages. Considering the different biological traits of the two lines, we suggest the use of the ‘biotype’ terminology to designate the two biological entities and discuss their implications for integrated pest management.

Chemical signals have an important role in the survival of many animals and are essential for the exploration of the resources available in their habitat. All phytophagous insects, including dipterans, use diverse chemical compounds released by plants as olfactory signals to locate their hosts. Spotted wing drosophila, Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), is a generalist fly that uses numerous plants as hosts. In this study, we evaluated the attractiveness of extracts from six plants commonly used as ornamental and medicinal plants in the southern region of Mexico. When the flies were exposed to Piper auritum Kunth (Piperaceae) extract, we observed a stimulating-attracting effect, especially on females, whereas the other five extracts showed no significant differences from their respective controls. In addition, gas chromatography coupled with mass spectrometry analysis of the P. auritum extract revealed 11 compounds, where safrole and methyl eugenol (ME) showed the highest concentrations of all the compounds found. ME has been shown to attract flies, mainly males of the genus Bactrocera. In this case, we found a stronger effect on female D. suzukii, indicating a potential effect of ME as a kairomone that mainly stimulates the attraction behavior of females.

The polyphagous shot hole borer (PSHB) beetle, Euwallacea fornicatus (Eichhoff) (Coleoptera: Curculionidae, Scolytinae), and its phytopathogenic fungal symbiont (Fusarium euwallaceae Freeman et al.) threaten commercial and urban tree species worldwide. This pest–fungus complex has been newly discovered in the commercial deciduous fruit industry (Western Cape, South Africa), where its effect is still unknown. This study explored the impact of PSHB infestation on fruit quality and plant water-use efficiency (WUE) – as indicated by carbon and nitrogen stable isotope ratios – of commercially cultivated Packham's Triumph pear trees within the first year of invasion, as well as changes in phenotypic plasticity (trait expression range). The impact of PSHB infestation is currently most evident in fruit quality traits, with a clear distinction between the control and most densely attacked tree categories. Fruit and leaf traits showed high variation and a significant change in phenotypic plasticity. Increased PSHB attack density was associated with smaller, duller-toned, sweeter fruit at the time of harvest and data tended towards reduced plant WUE. Producers can expect significant variation in fruit quality and plant WUE even in hosts without branch dieback, visible plant stress or extensive beetle breeding, especially in orchards where infestations persist beyond the first year. These findings necessitate additional research to describe the long-term impact, examine the threat to other deciduous fruit crops and cultivars and assess the need for adapted management or harvesting methods.

Effects of sub-nanogram doses of acetamiprid, dimethoate, flupyradifurone, and sulfoxaflor on courtship, mating, and olfactory host finding of the parasitic wasp Lariophagus distinguendus – N. Schöfer, G. Ratschmann & J. Ruther (https://doi.org/10.1111/eea.13444).

Sensory stimuli are essential for arthropod survival and reproduction. Given the widespread use of vibrational communication among diverse taxa, exploiting vibrational senses has great potential for successful pest management. In this review, we summarize our recent findings on vibration-based pest management and future perspectives in the context of integrated pest management. We first examine the management of whiteflies – the tobacco whitefly, Bemisia tabaci (Gennadius) and the greenhouse whitefly, Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae) – in various facilities where tomatoes are cultivated. We then explore the recent application of vibration for the control of fungus gnats of the genus Neoempheria (Diptera: Mycetophilidae) infesting shiitake mushrooms. Finally, we discuss the control of the brown-winged green stink bug, Plautia stali Scott (Hemiptera: Pentatomidae), a pest of fruit trees in Japan. Notably, our trials have demonstrated that vibrational treatments are profitable not only for reducing pest populations but also for indirect benefits such as increased crop yields or the enhancement of pest control effectiveness.

Leaves of large-leaved lime, Tilia platyphyllos Scop. (Malvaceae), harbor colonies of Eriophyes tiliae (Pagenstecher) (Acari: Eriophyidae), capable of modifying the leaf structure (inducer of nail-galls) and physiology. The aerial organs of T. platyphyllos have traditionally been consumed for their high antioxidant capacity, related to the rich polyphenol profile. Here, we investigated the polyphenol profiles and antioxidant activity of T. platyphyllos non-galled leaves and galls to determine the changes induced by the mite in a Chilean environment with high ultraviolet (UV) radiation. Phenolic compound identification in the methanol extracts of non-galled leaves and galls was carried out through HPLC. Furthermore, the antioxidant activity of the extracts was quantified through spectrophotometry, and it was compared with the standards of the three major phenolic compounds of both organs. Nine phenolic compounds were detected in non-galled leaves and galls, with no differences between the two organs, except for the absence of gallic acid in galls. The concentration of phenolic compounds did differ significantly between the two conditions. In leaf galls, epicatechin and cyanidin-3-glucoside concentrations and antioxidant capacity increased significantly compared to non-galled leaves. As chlorogenic acid and cyanidin-3-glucoside are active phenols responding to UV radiation stress, their concentration in T. platyphyllos leaves could be a response to the high UV radiation occurring in Chile during spring and summer. The phenolic compounds detected here have been reported to be potent antioxidants, that are probably potentiated by E. tiliae for its own protection against UV-B radiation, as the two most abundant compounds in the galls exhibited the highest capacity to reduce ABTS and DPPH radicals. However, we do not rule out the participation of phenolics in protection against natural enemies of the gall mite, as chlorogenic acid and epicatechin are powerful antifeedants.

A new approach to supplying foods and feeds that are high in protein has emerged in the form of insect farming. Insect-farmed food may also serve as part of a sustainable diet for humans. The mealworm Tenebrio molitor L. (Coleoptera: Tenebrionidae) is the most widely consumed insect worldwide. In this study, 10 larval diets were tested in the laboratory to determine their suitability for mass-feeding mealworms at 28 °C and 60–65% r.h., in a completely randomized design. Various larval diets had a significant impact on the biological features of T. molitor. The larvae, pupae, and adults were greater on diets containing wheat bran alone and wheat bran in combination with maize and porridge. Larval mortality was significantly higher (60.7%) on a diet with porridge alone, compared to a control diet, followed by diets with porridge in combination with barley (55.6%) or maize (50.6%). Sex ratio was also affected by the tested larval diets. Female hatch (65%) was higher than male hatch (35%) on diet containing wheat bran alone as compared to all other diets. The findings contribute to optimizing mealworm rearing practices for sustainable food production and promote the potential use of mealworms as a viable protein source – especially livestock diets based on mealworm reared on wheat bran show promise.

Guidelines for conducting, analyzing, and interpreting electrical penetration graph (EPG) experiments on herbivorous piercing-sucking insects – G. P. Walker, A. Fereres & W. F. Tjallingii (https://doi.org/10.1111/eea.13434).

The sweet potato whitefly, Bemisia tabaci MED (Gennadius) (Hemiptera: Aleyrodidae), is highly harmful to solanaceous crops. The use of essential oils (EOs) is promising for the management of several insect pests, promoting both lethal and sublethal effects. This study aimed to evaluate the effects of sublethal concentrations of Pelargonium graveolens L'Her (Geraniaceae) EO on the feeding behavior of B. tabaci MED on tomato plants (Solanum lycopersicum L., Solanaceae). For this research, the electrical penetration graph (EPG) technique was used to monitor whitefly stylet activities on their host plants. Two sets of plants were previously sprayed with two concentrations of EO (the LC₂₅ and LC₅₀, which were determined in a mortality test), a third set was treated with the insecticide cyantraniliprole, and a fourth set received a control treatment. Our results indicate that the insecticide cyantraniliprole and the EO could both reduce the stylet feeding activity of B. tabaci MED, as well as reduce the number and duration of phloem sap ingestion events (waveform E2), which could avoid or reduce the transmission of viruses. Thus, the application of sublethal concentrations of P. graveolens EO, as well as exposure to cyantraniliprole, negatively affected the feeding behavior of B. tabaci MED. This information may contribute to the management of this pest and the reduction of the incidence of viruses in tomato production.

Vibrational communication in the Auchenorrhyncha is an avenue of growing interest, with many pesticide-free vibrational pest control programmes against auchenorrhynchan agricultural pests continuing to be developed around the world. Passion vine hoppers (PVH), Scolypopa australis (Walker) (Hemiptera: Ricaniidae), are an economically damaging pest species in New Zealand, where they facilitate the growth of sooty mould in kiwifruit orchards. Scolypopa australis is already known to use vibrational signals, therefore a further understanding of the spectral and temporal characteristics of its calls will be an essential next step to developing vibration-based pest management strategies. Here, we aimed to characterise the properties of spontaneous S. australis calls in solitary and intrasexual communication contexts. We used laser Doppler vibrometry to record vibrational signals produced by male and female S. australis (separately), when in groups of three or individually. We sorted calls and call sub-units (syllables) into groups based on cluster analyses of various spatio-temporal parameters. We define four male calls and three female calls, and newly describe a ‘two-syllable’ calling structure that may be involved in male intrasexual competition. Certain syllables were more prevalent at the beginning or end of calls for males, and were more homogenously distributed throughout calls for females. The types of calls used differed between single males and groups, with more energetically intense call types observed in the group settings. Additional studies on the behavioural context of S. australis vibrational calls and their responses to playback of such calls will be necessary to assess the viability of vibration-based pest management for this species.