• Journal of Microbiology and Biotechnology
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• v.28 no.6
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• pp.976-986
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• 2018

Knowledge about the gut bacterial communities associated with insects is essential to understand their roles in the physiology of the host. In the present study, the gut bacterial communities of a laboratory-reared insecticide-susceptible (IS), and a field-collected insecticide-resistant (IR) population of a major rice pest, the brown planthopper Nilaparvata lugens, were evaluated. The deep-sequencing analysis of the V3 hypervariable region of the 16S rRNA gene was performed using Illumina and the sequence data were processed using QIIME. The toxicological bioassays showed that compared with the IS population, IR population exhibited 7.9-, 6.7-, 14.8-, and 18.7-fold resistance to acephate, imidacloprid, thiamethoxam, and buprofezin, respectively. The analysis of the alpha diversity indicated a higher bacterial diversity and richness associated with the IR population. The dominant phylum in the IS population was Proteobacteria (99.86%), whereas the IR population consisted of Firmicutes (46.06%), followed by Bacteroidetes (30.8%) and Proteobacteria (15.49%). Morganella, Weissella, and Enterococcus were among the genera shared between the two populations and might form the core bacteria associated with N. lugens. The taxonomic-to-phenotypic mapping revealed the presence of ammonia oxidizers, nitrogen fixers, sulfur oxidizers and reducers, xylan degraders, and aromatic hydrocarbon degraders in the metagenome of N. lugens. Interestingly, the IR population was found to be enriched with bacteria involved in detoxification functions. The results obtained in this study provide a basis for future studies elucidating the roles of the gut bacteria in the insecticide resistance-associated symbiotic relationship and on the design of novel strategies for the management of N. lugens.

• The Plant Pathology Journal
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• v.37 no.3
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• pp.299-306
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• 2021

Pollination is an essential process for plants to carry on their generation. Pollination is carried out in various ways depending on the type of plant species. Among them, pollination by insect pollinator accounts for the most common. However, these pollinators have be decreasing in population density due to environmental factors. Therefore, use of artificial pollination is increasing. However, there is a lack of information on microorganisms present in the artificial pollens. We showed the composition of bacteria structure present in the artificial pollens of apple, kiwifruit, peach and pear, and contamination of high-risk pathogens was investigated. Acidovorax spp., Pantoea spp., Erwinia spp., Pseudomonas spp., and Xanthomonas spp., which are classified as potential high-risk pathogens, have been identified in imported pollens. This study presented the pollen-associated bacterial community structure, and the results are expected to be foundation for strengthening biosecurity in orchard industry.

• Journal of Korean Society of Forest Science
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• v.102 no.1
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• pp.97-106
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• 2013

The present study is aimed to evaluate forest health in a fragmented urban forest using characteristics of insect communities. Ants (Formicidae) and ground beetles (Carabidae) surveyed by pitfall trap method in the Hongneung forest located in the urban area of Seoul were compared with those in the Gwangneung forest. The Gwangneung forest is supposed to be health due to its high biodiversity and well-conserved nature. Ants of the Hongneung forest was much more abundant compared with those of the Gwangneung forest. However, ground beetles showed the opposite patterns; much more abundant in the Gwangneung forest than in the Hongneung forest. Species richness was higher in the Gwangneung forest than in the Hongneung forest, but species diversity was higher in the Hongneung forest. In the Hongneung forest, forest specialist species and generalist species were balanced, whereas few forest specialists dominated in the Gwangneung forest. This dominance decreased species diversity in those Gwangneung forest. Thus, characteristics of insect community in the Hongneung forest were greatly different with those in the Gwangneung forest.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.4
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• pp.368-383
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• 2014

Climate change is expected to affect population density, phenology, distribution, morphological traits, reproduction and genetics of insects, and even in the extinction of insects. To develop novel research subjects for predicting climate change effect, basic information about biological and ecological data on insect species should be compiled and reviewed. For this reason, this study was conducted to collect the biological information on insect pests that are essential for predicting potential damage caused by insect pests in future environment. In addition, we compared domestic and foreign research trends regarding climate change effect and suggested future research subjects. Domestic researchers were rather narrow in the subject, and were mostly conducted based on short-term monitoring data to determine relationship between insects and environmental variables. On the other hand, foreign researches studied on various subjects to analyze the effect of climate change, such as changes in distribution of insect using long-term monitoring data or their prediction using population parameters and models, and monitoring of the change of the insect community structure. To determine change of the phenology, distribution, overwintering characteristics, and genetic structures of insects under climate change through development of monitoring technique, in conclusion, further researches are needed. Also, development of population models for major or potential pests is important for prediction of climate change effects.

• Korean Journal of Ecology and Environment
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• v.54 no.1
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• pp.61-70
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• 2021

The effects of forest type and fragmentation of forests by a road on the beetle community were investigated in the Gwangneung Forest, South Korea. Beetles were collected monthly using pitfall traps and by sweeping at 16 sites (eight in coniferous forests and eight in deciduous forests) for one year from April 1993 to April 1994, excluding winter. A total of 17,616 beetles belonging to 271 species from 39 families were collected. Among them, Synuchus cycloderus was the dominant species, with 14,060 individuals accounting for 80% of the total population. The influence of forest type (coniferous and deciduous) or sampling region (fragmented by a road) on species richness(number of species) was observed. We found that species richness was substantially different depending on the sampling method and taxa used. Beetles collected using pitfall traps responded more sensitively to habitat types than those collected by sweeping. Four dominant families differently responded to forest fragmentation and forest types. Carabidae was influenced by forest fragmentation, whereas Staphylinidae and Curculionidae were influenced by forest types. Chrysomelidae was not influenced.

• Journal of Ecology and Environment
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• v.36 no.2
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• pp.125-129
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• 2013

The study on the major insect pests community of Hibiscus syriacus. There were three orders, seven families, and thirteen species of insects harmful to H. syriacus. When the harmful insects eating H. syriacus were classified according to which part of the flower they were eating, insects eating leaves, which considered of nine species four families and one order, accounted for 69.23 %. Insects sucking juice from leaves and stems comprised 15.38 %, with two species two families and two orders, while insects eating seeds comprised 15.38 %, with two species two families and two orders. Aphis gossypii appeared once per H. syriacus from the fourth week of April to the second week of June, appearing the most at a rate of 69.05 per H. syriacus during the first week of May. Dichocrocis surusalis appeared at a rate of 0.05 per H. syriacus during the third week of April and regularly appeared from the first week of July to the second week of September. Nortacha derogata appeared at a rate of 0.1 per tree during the first week of May, after which it continuously appeared until the third week of October. Anomis privata appeared at a rate of 0.05 per tree during the first week of May and continuously occurred from the fourth week of June to the fourth week of October. Its occurrence was most frequent at 2.30 per tree during the third week of September.

• Journal of Wetlands Research
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• v.19 no.1
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• pp.155-163
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• 2017

This study was conducted to know the wetland insect diversity at Gonggeom-ji in Sangju city which is the first designated paddy field wetland protection by the Ministry of Environment of Korea in 2011. Data was collected at four times from March to November in 2014 using by Searching, Sweeping and Pitfall trap methods. In this study a total of 227 species of 205 genera belonging to 78 families from 8 orders were collected and individuals were 1,327. Among them, the order of Coleoptera was the most species-rich (42.73%), Hemiptera was the second order (22.47%). In the total diversity index (H') was 6.339 that means highly positive. Dominant Index (DI) was 0.143, Evenness index (EI) was 0.810. Over all survey periods, interspecies competitiveness was high, and community stability was also high. Therefore Gonggeom-ji wetland revealed stable and positive environmental situation.

• Journal of Agricultural Extension & Community Development
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• v.30 no.1
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• pp.1-13
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• 2023

This study aims to examine the effect of healing program using insect. For the insect resources, the program uses 3 species of emotional insects. The subjects were a total of 29, the elderly with mild dementia and adults with developmental disabilities in the facility. The activities are 9 programs in total and each program takes 2 hours once a week. For data collection, we measured a blood pressure, stress level using autonomic nervous system activity, and scale of happiness, depression and insomnia by a survey. The datas were collected every week before and after the program. As a result of paired-sample t-test analysis, the participants of the agro-healing program using insects had positive effects as follows: reducing a depression, relieving a symptom of insomnia and stabilizing a blood pressure. Through the results of this study, it was possible to confirm the positive effects of the agro-healing program using insects. If farms lead agro-healing program using insects on their own, it could be expected to contribute to improve the quality of life through agriculture as well as to improve the farms' income.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.4 no.1
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• pp.1-8
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• 2023

In this study, we aimed to quantify the population size and spatial distribution of three predatory Scarites species in coastal sand dunes. In June and August 2014, 252 pitfall traps were utilized to conduct a trapping web analysis at three distinct sites with varying vegetation dominance values. Scarites sulcatus had the largest estimated population in a 10 m² area with a habitat density of 36.6 in a Vitex rotundifolia community area (site B) in the June survey. In contrast, Scarites aterrimus had the largest population size with a habitat density of 2.9 in a Calystegia soldanella community area (site A) in the August survey. Spatial distribution analysis revealed that S. sulcatus dominated the Vitex rotundifolia community without preference for a particular site, whereas S. aterrimus and Scarites terricola pacificus were primarily observed on the beach. The results indicated that the three Scarites species in the Sohwang coastal sand dune region exhibited differences in their spatial and temporal distributions in the coastal dune ecosystem in order to avoid competition and predation. In conclusion, our findings can be utilized to estimate the population density of the genus Scarites on the Korean Peninsula. The outcomes of this study will contribute to estimating insect population densities on the Korean Peninsula and developing investigative assessment methodologies.

• Korean Journal of Environmental Biology
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• v.34 no.4
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• pp.233-239
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• 2016

The purpose of this study is to investigate the response of the soil mesofauna and ground-dwelling arthropods to vegetation structure and composition in a mountain pasture. The pasture mainly comprised five types of plant communities; Agrostis alba - Phleum pratense community, Poa pratensis community, Festuca ovina community, Rumex acetosella community, and the shrub assemblage comprised Spiraea miyabei-Spiraea salicifolia community. Soil chemical properties including the pH, EC and nutrient levels were influenced by plant communities. Plant-specific responses were observed for bacteria-feeding and plant-feeding soil nematodes. Collembola and Oribatida having the same feeding habit were influenced differently by plants. nMDS showed that the community of ground-dwelling arthropods were separated by vegetation types. Species numbers of arthropods were different among different plant communities. Our results indicate that vegetation structure and composition can influence both abundance of diversity of terrestrial fauna.