Publications by authors named "Xiangyun Ji"

The tri-trophic interaction of plants, insect herbivores, and entomoviruses is an important topic in ecology and pest control. The susceptibility of insect herbivores to entomoviruses (e.g.

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Background: The house fly is a public health pest due to its ability to transmit various pathogens worldwide. The suppression of house flies is frequently controlled by organophosphate and carbamate insecticides, but recurrent selection has led to the mutated target. To understand the spread and evolution of Mdace mutations in house flies, we sampled flies in eight different China provinces, sequenced, and then estimated the frequencies of mutations.

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Microplitis pallidipes Szépligeti (Hymenoptera: Braconidae) is an important parasitic wasp of second and third-instar noctuid larvae such as the insect pests Spodoptera exigua, Spodoptera litura, and Spodoptera frugiperda. As in other insects, M. pallidipes has a chemosensory recognition system that is critical to foraging, mating, oviposition, and other behaviors.

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Urbanization is a pressing challenge for earth's humans because it is changing not only natural environments but also agricultural lands. Yet, the consequences of cropland loss on pest insect populations that largely depend on these habitats remain largely unclear. We used a 17-year data set to investigate the dynamics of three moth pest species (i.

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Background: Tri-trophic interactions among plants, insect herbivores and entomopathogens are one of the hot topics in ecology. Although plants have been shown to impact the interactions between herbivores and entomopathogens, it is still unclear how plants affect the cellular immunity of herbivores to entomopathogens.

Results: The number of hemocytes and the proportion of two main cell types (granular hemocytes and plasmatocytes), plasmatocyte-spreading rate, apoptosis rate, two Spodoptera exigua caspase (SeCasp-1, SeCasp-5) activities and gene expressions were all higher and the activities and gene expression of S.

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Spodoptera exigua nucleopolyhedrovirus (SeNPV) has been successfully applied as a bioinsecticide against S. exigua, one of the most devastating pests worldwide. However, due to limited information, the molecular mechanisms underlying interactions between S.

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Background: Interactions between herbivorous insects and entomoviruses may depend on host plant, perhaps mediated through changes in herbivore innate immunity.

Results: Caterpillars (Spodoptera exigua) fed Glycine max had high viral loads and low melanization rates together with low melanization enzyme [PO, DDC, TH] activities and gene expressions. Caterpillars fed Ipomoea aquatica had low viral loads and high melanization, gene activities and gene expressions while those fed Brassica oleracea or artificial diet had intermediate levels of each.

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Article Synopsis
  • Urban agriculture is enhancing food security in major cities, with a focus on biodiversity's role in improving these systems.
  • Data from community rice farms in Shanghai (2001-2015) revealed that introducing soybean borders and neighboring diverse crops helped boost predator insects and reduce pests, leading to higher yields and profits.
  • Experiments confirmed that increasing crop diversity not only aids ecological sustainability but also optimizes the use of ecosystem services in urban environments.
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  • The study examines the ecological implications of adopting standardized agricultural production, which has not been extensively researched despite its promotion.
  • It introduces a Standardization of Green Production Index (SGPI) to evaluate the pre-, mid-, and post-production phases of peach cultivation, highlighting both the positive and negative impacts of agricultural processes.
  • The results, indicating varying levels of excellence in production practices, aim to assist decision-makers, ecologists, and farmers in implementing eco-friendly standardized agricultural methods.
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We determined the effects of parasitism by the endoparasitoid Microplitis pallidipes Szepligeti and/or nucleopolyhedrovirus (NPV) infection on hemocyte apoptosis of Spodoptera exigua (Hübner) larvae. Compared to healthy (control) larvae, larvae that were parasitized, virus-infected, or both all showed a significant increase in hemocyte apoptosis during 48-h observation period. The peaks of hemocyte apoptosis in parasitized, virus-infected and parasitized+infected larvae were at 12, 24 and 48 h after treatment, and were 86.

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The extensive use of chemical pesticides for pest management in agricultural systems can entail risks to the complex ecosystems consisting of economic, ecological and social subsystems. To analyze the negative and positive effects of external or internal disturbances on complex ecosystems, we proposed an ecological two-sidedness approach which has been applied to the design of pest-controlling strategies for pesticide pollution management. However, catastrophe theory has not been initially applied to this approach.

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Many studies have supported the enemies hypothesis, which suggests that natural enemies are more efficient at controlling arthropod pests in polyculture than in monoculture agro-ecosystems. However, we do not yet have evidence as to whether this hypothesis holds true in peach orchards over several geographic locations. In the two different geographic areas in eastern China (Xinchang a town in the Shanghai municipality, and Hudai, a town in Jiangsu Province) during a continuous three-year (2010-2012) investigation, we sampled arthropod pests and predators in Trifolium repens L.

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Article Synopsis
  • - The study compared arthropod communities in peach orchards with and without ground cover, finding that orchards with ground cover had higher populations of beneficial, neutral, and phytophagous arthropods, although the total number of arthropods was similar in both orchards.
  • - In terms of diversity metrics, the orchard with ground cover exhibited significantly greater species richness, higher Shannon's diversity, and lower dominance compared to the orchard without ground cover.
  • - Stability indices showed no significant differences between the two orchards, but certain ratios (Nn/Np, Nd/Np, Sn/Sp) were notably higher in the orchard with ground cover, with different correlation patterns observed regarding diversity and stability metrics in each orchard
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Background: Nucleopolyhedrovirus (SeNPV) and Microplitis pallidipes are important biological control agents of Spodoptera exigua populations. The interactions between these agents and their combined effect on pest control were investigated in the laboratory and in commercial greenhouses.

Results: Microplitis pallidipes searched for and deposited eggs in more healthy larvae than virus-infected larvae 3 days after viral infection.

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The study on the nuclear polyhedral virus epidemic of Spodoptera litura under effects of temperature showed that at above 29 degrees C, S. litura larvae started to die 2-3 d after virus-inoculation, and reached the peak 4-5 d after the inoculation. The mortality and death velocity of virus-infected host larvae were increased with increasing incubation temperature.

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