Entomologia Experimentalis et Applicata最新文献

Zoophytophagous predators can be beneficial for controlling crop pests in greenhouses. Yet, they can also cause significant economic damage. More zoophagous and effective predator lines can be developed by selectively breeding highly zoophagous individuals. Hence, artificial selection based on the degree of zoophagy in zoophytophagous predators can improve their efficiency as biocontrol agents while reducing the risk of crop damage. However, artificial selection on zoophagy could cause changes in other behavioral or life history traits due to genetic correlation or pleiotropy. These changes can affect the ecological conditions in which biological control agents work. We created highly and lowly zoophagous lines of Dicyphus hesperus Knight (Hemiptera: Miridae) using artificial selection. We tested genetic correlations between zoophagy and food patch exploitation equity in four generations of artificial selection. The results revealed that females were more zoophagous than males. The broad sense heritability (H²) of zoophagy was 0.38 in females and 0.29 in males. Artificial selection on zoophagy led to decreased food patch exploitation equity, yet the traits were not genetically correlated. Our results suggest that artificial selection can be used to develop lines of D. hesperus that enhance the benefits of biological control and modify ecological factors such as prey density and distribution.

The predatory bug Cyrtorhinus lividipennis Reuter (Hemiptera: Miridae) is an important biological control agent for planthoppers, such as Nilaparvata lugens (Stål) (Hemiptera: Delphacidae), and leafhoppers in rice fields (Oryza sativa L., Poaceae). In this study, the sublethal effects of azoxystrobin and difenoconazole, two fungicides extensively used in rice production, on this predatory bug were investigated. The results indicated that exposure to the two fungicides at the third instar had no influence on developmental duration, but difenoconazole resulted in a 25.2% decrease in the lifespan of adult males. When exposed as newly emerged adults, azoxystrobin caused a 33.5% decrease in female longevity. The pre-oviposition period of azoxystrobin-treated females mating with azoxystrobin-treated males was shortened by 44.9%, compared with the control, whereas the pre-oviposition period of difenoconazole-treated females mating with control males was lengthened by 32.2% compared with the control group. However, the two fungicides had no effect on fecundity and egg hatchability. Furthermore, the two fungicides did not impact the average consumption of C. lividipennis of N. lugens individuals. They did stimulate the response of C. lividipennis males to rice plants infested by N. lugens in a two-choice H-shaped olfactometer test. Also, the predatory capacity of C. lividipennis males was increased after exposure to difenoconazole, whereas the predatory capacity of females was decreased after exposure to the two fungicides. Overall, our results indicated that azoxystrobin and difenoconazole pose no notable risk to C. lividipennis. These findings establish a foundation for the rational and coordinated utilization of fungicides and biological control agents in rice ecosystems.

Spatial and temporal distribution of food resources influences predatory insects' foraging and dispersal behavior. Orius insidiosus (Say) (Hemiptera: Anthocoridae) is a good biological control agent of western flower thrips (WFT), Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), in the strawberry crop and consumes two-spotted spider mite (TSSM), Tetranychus urticae Koch (Acari: Tetranychidae), and pollen as well. Augmentative biological control programs may fail if, following release, predators disperse from the crop. We studied the dispersal of O. insidiosus as a function of pollen availability, density of their main prey WFT, and the presence of the alternative prey TSSM, within and between strawberry plants. We found that O. insidiosus remained on the flowers during the 24 h of the assay. The dispersal of predators to a neighboring flower with thrips was approximately six times greater from a flower without pollen than from a flower with pollen. When TSSM was the only prey available, O. insidiosus colonized the leaves, and its dispersal within the plant was greater. At the plot scale, the predator dispersal from the release plant to other plants also depended on the presence of flowering plants and prey. Our results highlight the importance of flowering plants and pollen availability in enhancing the persistence of O. insidiosus in strawberry plants. Releases of this predator in the strawberry crop should be after the beginning of flowering, even at low WFT densities.

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.