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BACKGROUND: Entomophagous fungi (EPF) not only directly kill insect pests, but also colonize plants and improve their resistance against pests. However, most previous research has focused on Beauveria bassiana and Metarhizium anisopliae, and there are few reports on whether other EPF can enhance resistance against pests via endogenous colonization. Herein, an EPF strain was isolated from diseased larvae of Spodoptera litura in a soybean field, and subjected to genome‐wide sequencing at the chromosomal level. The pathogenicity of the isolate toward various pest insects was evaluated, and the ability to colonize plants and induce resistance against phytopathogens and insect pests was tested. RESULTS: The purified isolate was identified as M. rileyi and designated MrS1Gz1–1. Biological assays revealed its strong pathogenicity toward five insect pests belonging to Lepidoptera and Hemiptera. Furthermore, the strain inhibited the growth of soil‐borne plant disease caused by Sclerotinia sclerotiorum in vitro. It colonized plants as an endophyte via soil application, thereby inducing plant resistance‐related genes against phytopathogen infection, and it disrupted the feeding selectivity of S. litura larvae. CONCLUSION: M. rileyi MrS1Gz1–1 has potential as a broad‐spectrum microbial control agent that can induce resistance against phytopathogens and insect pests feeding as an endotype. The complete genome provides a valuable resource for exploring host interactions. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Harmonia axyridis Pallas (Coleoptera: Coccinellidae) is an important natural enemy of aphids. Plant species and plant health conditions can affect the behavior of H. axyridis. To determine plant effects on this lady beetle, we examined beetle responses to four cover crops: coriander (Coriadrum sativum L., Apiales: Apiaceae), marigold (Tagetes erecta L., Asterales: Asteraceae), sweet alyssum (Lobularia maritima L., Brassicales: Brassicaceae), and alfalfa (Medicago sativa L., Fabales: Fabaceae). Our goal was to better understand this predator's ovipositional behavior in response to different plants and its olfactory response to the aphid‐induced volatiles from these plants. RESULTS: We found that this lady beetle did not have any significant oviposition preference among the four plant species, but H. axyridis preferred to lay eggs on the lower surface of leaves, regardless of the plant species. H. axyridis females had a significant preference for aphid‐infested marigolds, but were not attracted by any of the other three cover plants or marigolds without aphid damage. Compared to the uninfested marigold plants, the emission of 12 compounds significantly increased on the aphid‐infested marigolds, and two of them were attractive to H. axyridis under suitable concentrations. CONCLUSION: H. axyridis did not show any significant oviposition preference among the four cover crops. Aphid‐infested marigolds can attract H. axyridis. Indole and terpinen‐4‐ol mediated lady beetle attraction. These synomones have potential for manipulating populations of H. axyridis as a component of conservation biological control. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND Thrips, Megalurothrips usitatus, usually display aggregation behavior, which is probably mediated by a male‐produced aggregation pheromone. Aggregation pheromones are species‐specific, and can be used to develop commercial lures for monitoring and mass‐trapping of pests. The active components of the aggregation pheromone for four thrips species have been identified. However, the components of M. usitatus‐produced aggregation pheromone are still not clear. RESULT: Y‐tube olfactometer assays showed that both male and virgin female M. usitatus were significantly attracted to male but not female volatiles. This was additionally supported by electroantennogram (EAG) assays. Coupled gas chromatography‐electroantennogram detection (GC‐EAD) showed that one component of male‐specific odors elicited a significant electrophysiological response. This compound was characterized as (2E,6E)‐farnesyl acetate, which is structurally different from the active components of the aggregation pheromones of other reported thrips species. Electroantennal responses of M. usitatus increased with increasing doses of synthetic (2E,6E)‐farnesyl acetate. Additionally, this compound significantly attracted adults in laboratory behavioral bioassays. Under field conditions, sticky traps with synthetic (2E,6E)‐farnesyl acetate caught 1.5‐7‐fold more M. usitatus than controls, and this effect of the compound at a dose of 60 μg lasted at least 6 days. CONCLUSION: (2E,6E)‐Farnesyl acetate was identified as the male‐produced aggregation pheromone of M. usitatus. It could attract this thrips species under laboratory and field conditions, suggesting considerable potential as a commercial application to control M. usitatus populations. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Background: Honeydew is valuable food source for predators that can build predator numbers and strengthen biological control. Honeydew excreted by hemipterans often supplements the diets of their predators and parasitoids. However, dense sticky honeydew also creates a difficult foraging environment, potentially limiting predator efficiency. Results: We examined the benefits and costs of honeydew excreted by the pear psylla (Cacopsylla chinensis [Yang and Li]) for its key predator in much of Asia, the anthocorid bug Orius sauteri (Poppius). We found these predators spent more time foraging and laid more eggs in the presence of psyllid honeydew compared to the control. However, predators more often foraged among psylla without honeydew than those coated in honeydew. This suggests that while O. sauteri recognized honeydew as a useful cue to prey presence, the predators were more likely to attack pear psylla lacking the sugary excretion. In foraging trials, honeydew consistently reduced the number of psyllids killed by the predator, suggesting it limited O. sauteri mobility or reduced the nutritional value of psyllids as prey. We also found slowed development, reduced longevity, and reduced fecundity of O. sauteri reared on moth eggs (Sitotroga cerealella [Olivier]) coated in honeydew compared to those reared on moth eggs alone. Conclusion: Altogether, our results suggest that psyllid honeydew could serve as a prey‐location and oviposition cue for O. sauteri. However, honeydew also limited predator foraging with the potential to limit biological control. More generally, honeydew might form an important type of defense for stationary feeders like psyllids. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Neuropeptide F (NPF) is an intercellular signaling molecule that mediates many physiological and behavioral processes. However, the function of neuropeptide F in mediating the feeding behavior of Locusta migratoria has been unclear. RESULTS: The neuropeptide F 1 precursor cDNA from L. migratoria was obtained and analyzed, and its amino acid sequence deduced. Mature LmiNPF1 was composed of 36 amino acids and was similar to that of Schistocerca gregaria. The spatial and temporal expression profiles of LmiNPF1 were investigated. LmiNPF1 was primarily expressed in the central nervous system, especially in the brain, and the expression levels were higher during the day than during the night. However, starvation activated LmiNPF1 expression increases, and downregulation of LmiNPF1 inhibited locust feeding behavior. CONCLUSION: LmiNPF1 promotes the feeding behavior of the locust and is a potential molecular target to control locust feeding. © 2018 Society of Chemical Industry The locusts (Locusta migratoria) tend to overeat with the increase of neuropeptide F 1, and those become inappetent with the decrease of neuropeptide F 1. [ABSTRACT FROM AUTHOR]

Four major tea management practices (organic, pollution-free, conventional, and semi-natural) are employed in Chinese tea plantations at present. These practices can induce changes in the physiochemical parameters, microorganism community and enzyme activity in tea plantation soil. However, understanding of their effects on soil nematodes is still scarce. This study aimed to investigate whether and how different management practices affect the biodiversity, function, and structure of soil nematode communities in tea plantation habitats. The soil nematode community structures and ecological indices were determined from the soil samples collected more than 6 y after their respective farming practices were first applied, and different management practices did not greatly affect soil nematode community evenness or species diversity, but organic practice increased nematode trophic diversity, common species diversity, and species richness. Pollution-free practice considerably increased fungivorous nematodes, and both pollution-free and conventional practice decreased bacterivorous nematodes markedly in the subsurface layers of soil. Predator and omnivorous nematodes were found to be more abundant in semi-natural plantation. Organic practice was more sustainable and suitable for tea cultivation, with the greatest biodiversity, best nutrient conditions, higher and more stable C/N ratio and lower interference in the food web. [ABSTRACT FROM AUTHOR]

The front cover image is based on the Original Article A sticky situation: honeydew of the pear psylla disrupts feeding by its predator Orius sauteri by Wang‐Peng Shi et al., https://doi.org/10.1002/ps.5498. [ABSTRACT FROM AUTHOR]