• 한국균학회소식:학술대회논문집
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• 2016.05a
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• pp.13-13
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• 2016

Insects constitute the largest and most diverse group of animals in the world. They also serve as the hosts or nutrient sources for an immense assemblage of pathogens, parasites, and predators. More than 700 fungal species from 100 genera have adopted an entomopathogenic lifestyle. Although entomopathogenic fungi were studied as only biocontrol agents against a variety of pests in various countries, it has been recently focused their additional roles in nature. They are antagonists to/against plant pathogens, endophytes, and possibly even plant growth promoting agents. The potential antimicrobial effect against fungal plant pathogens by an isolate of entomopathogenic fungi including Beauveria bassiana, Lecanicillium spp., and Isaria fumosorosea have been reported since late 1990s, but wasn't reported pathogenicity of the isolate against pests. Later, a Canadian Lecanicillium sp. isolate and L. longisporium isolated from Vertalec$^{(R)}$ showed simultaneous control effect against both aphid and cucumber powder mildew. Therefore, the antimicrobial activities of 342 fungi isolates collected from various regions and conditions in Korea were evaluated against plant pathogenic fungus Botrytis cinerea using dual culture technique on agar plate. As a result, 186 isolates (54.4%) shown the antifungal activity against B. cinerea. The culture filtrates of selected fungi completely suppressed the growth of the microorganisms, indicating that suppression was due to the presence of antimicrobial substances in the culture filtrate. Mode of action of these fungi against insect involves the attachment of conidia to the insect cuticle, followed by germination, cuticle penetration, and internal dissemination throughout the insect. During infection process, secreted enzymes, proteinous toxins, and/or secondary metabolites secreted by entomopathogenic fungi can be used to overcome the host immune system, modify host behavior, and defend host resources. Recently, secondary metabolites isolated from entomopathogenic fungi have been reported as potential bioactive substances. Generally, most of bioactive substances produced by entomopathogenic fungi have reported low molecular weight (lower than 1,000 g/mol) as peptide and, in contrast the high molecular weight fungal bioactive substances are rare. Most substances based on entomopathogenic fungi were shown antimicrobial activity with narrow control ranges. In our study we analyzed the antimicrobial substances having antagonistic effects to B. cinerea. Antimicrobial substances in our fungal culture filtrates showed high thermostability, high stability to proteolytic enzymes, and hydrophilicity and their molecular weights were differed from substance. In conclusion, entomopathogenic fungi showed pathogenicity against insect pests and culture filtrate of the fungi also shown to antimicrobial activity. In the future, we can use the entomopathogenic fungi and its secondary metabolites to control both insect pest control and plant pathogenic fungi simultaneously.

• Korean journal of applied entomology
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• v.58 no.3
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• pp.251-258
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• 2019

A series of studies were conducted to monitor the seasonal occurrences of onion thrips (Thrips tabaci) and allium leafminers (Acrolepiopsis sapporensis) in northern-type garlic fields, and to evaluate their susceptibility to insecticides. The results showed that the T. tabaci population density increased from mid- March to mid-June, that of A. sapporensis began to increase in mid-March and peaked twice by early July. Also, using recommended concentrations, the insecticidal activities of nine insecticides against these two pests were evaluated. Under laboratory conditions, clothianidin SC, chlorfenapyr EC, dimethoate EC, imidacloprid WP, and cyantraniliprole + thiamethoxam WG insecticidal activities against T. tabaci were all 100%, as well as. those of cyantraniliprole EC, pyridalyl EW, spinetoram SG and abamectin + chlorantraniliprole SC against A. sapporensis. Insecticides, with high insecticidal activities, were evaluated on the two pests under laboratory conditions, and the results showed that all the insecticides exhibited strong insecticidal activities, and the mortality of two pests was >90%.

• The Korean Journal of Pesticide Science
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• v.17 no.4
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• pp.402-410
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• 2013

Insect pests damages are increasing on the field of Lycium chinense under environment- friendly management Thus, we was to monitor the occurrence of pests on organic L. chinense in Chungnam Cheongyang and, insecticidal effect of eco-friendly agricultural materials (EFAMs) were tested against major pests. When the buds come out, injury by L. chinense was very high causing the high population density of Myzus persicae in late May and early June, and the injury by Lema decempunctata was increased from mid-June. Otherwise, injuries by Eriophys macrodonis, Henosepilachna vigintioctomaculata and Hedma spp. were continued throughout the growing season. From the fruit held in late July, Hemipteran insects including Plautia stali and Halyomorpba balys were sucking the fruit, and their injury to L. chinense were gradually increased. For the eco-friendly environmental control of M. persicae, L. decempunctata and E. macrodonis, EFAMs containing Sophora flavescens, Melia azedarach (Chinaberry), Chenopodium ambrosioides (Mexican tea), Quassia amara (Amargo), Stemona sessilifolia, Sophora seeds and Nepeta cataria (Catmint), were selected and used to control the insect pests. Control effects of the mixed extract with S. flavescens and Sophora seeds against M. persicae and L. decempunctata were higher than any other EFAM as 84.0% and 86.6%, respectively. In case of E. macrodonis, its control effect was good with the mixed extract with S. flavescens, C. ambrosioides and M. azedarach.

• International Journal of Industrial Entomology and Biomaterials
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• v.17 no.2
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• pp.181-187
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• 2008

An entomopathogenic fungus, Paecilomyces fumosoroceus SFP-198 was isolated in Kyungbuk province, Korea and screened out for the control of Trialeurodes vaporariorum nymphs. It showed 72.5% efficacy against second instars of T. vaporariorum nymphs at 6 days after treatment in the laboratory. To select an active ingredient for the mass production and the formulation, SFP-198 culture products were compared based on their insecticidal activities against T. vaporariorum nymphs. Among them, conidia and blastospores showed much higher insecticidal activity than supernatants. Furthermore, SFP-198 conidia were more heat-resistant than blastospores, and also powder form of conidia was more stable than their suspension form. SFP-198 conidia showed high pathogenicity on not only T. vaporariorum but also Tetranychus urticae in the glasshouse. This result suggested that SFP-198 conidia can be used as a multi-targeting biological control agent against sucking agri- cultural pests, such as whiteflies and mites.

• Korean journal of applied entomology
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• v.63 no.1
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• pp.75-76
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• 2024

The ovicidal effect of plant extract mixture (5%cinnamon extract + 10% citronella oil + 30% citrus oil + 10% derris extract + 20% neem extract + 25% penetrating surfactant) against several major insect pests was tested using the spraying method. In the case of stink bugs, eggs tended to die during hatching. When treated with a plant extract mixture (500-times solution), mortality for Halyomorpha halys, Riptortus clavatus, Eurydema dominulus, Trialeurodes vaprarorium, Bemisia tabaci, Spodoptera exigua, and Agrotis ipsilon reached as high as 100%. Therefore, it is believed that industrialization will be feasible in the future.

• The Plant Pathology Journal
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• v.18 no.5
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• pp.231-236
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• 2002

Bemisia tabaci Genn. is an important pest worldwide because of its ability to cause damage by direct feeding and its role as a vector of some viruses including geminiviruses. The first report of Tobacco leaf curl virus (TLCV), a Geminiviruses, in Indonesia was in 1932 when the virus was found infecting tobacco plants in Central Java. The characteristic symptoms of TLCV included upward curling of the leaf edge, vein thickening, and sometimes the occurrence of enation on the underside of the leaves. Basic studies were carried out to elucidate the characteristics of TLCV transmission by its vector, B. tabaci. A single whitefly was able to transmit the virus and the efficiency of transmission was increased when the number of adult whiteflies was increased up to 20 per plant. Inoculation access period of 1 h could cause transmission up to 20% and the optimum inoculation access period was 12 h. Acquisition access period of 30 minutes resulted in 70% transmission while 1(10% transmission occurred with a 24-h acqui-sition access period. The virus was proven to be persistently but not transovarially transmitted. Discrete fragments of 1.6 kb were observed when polymerase chain reaction method was applied to detect the virus in viruliferous nymphs and individual adults of B. tabaci, while no bands were obtained from non-viruliferous nymphs and adults.

• The Korean Journal of Food & Health Convergence
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• v.6 no.2
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• pp.17-21
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• 2020

The response of honeybee (Apis mellifera L.) pollination on canola yield with reference to most suitable number of bee hive need per unit area of crops in order to meet optimum pollination needs and better economic yields by comparing number of hives and yield components an experiment was conducted at Beekeeping and Hill Fruit Pests Research, Station Rawalpindi during 2017-18 in complete randomized block design with two sets of four treatments for comparison: 1 hive acre^-1, 2 hives acre^-1, 3 hives acre^-1 and 0 hive acre^-1. The hives were kept inside the experimental area. Parameters were assessed: pollination density, pollinator's diversity, agronomic and economic yield. In case of pollination density, the cumulative mean abundance bee species revealed that at 1200 hours, Apis mellifera was the most abundant and frequent visitor with a mean population of 8.69 bees/plant followed by A. dorsata (0.72), Syrphid fly (0.2) and other pollinators. Minimum bee population was observed during 1400 hours, mainly due to the closure of flowers and partially due to high temperature (>35℃). Pollinator diversity revealed that A. mellifera was the most dominant pollinator of Brassica crop with highest abundance (71%). A. dosata ranked 2^nd (16%) followed by A. florea (6%) respectively.

• Korean journal of applied entomology
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• v.60 no.4
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• pp.357-361
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• 2021

Monitoring about nine high risk insect pests, Aceria diospyri, Bactrocera dorsalis, Bactrocera minax, Bactrocera tsuneonis, Cydia pomonella, Lobesia botrana, Proeulia sp., Solenopsis invicta and Stephanitis takeyai, were carried out in seven regions from April to October in 2020. A total of 12,045 traps/visual scouting were investigated in 222 points of 78 local sites of seven regions, resulting the nine species, A. diospyri, B. dorsalis, B. minax, B. tsuneonis, C. pomonella, L. botrana, Proeulia sp., S. invicta, and S. takeyai, were not detected. This study has been conducted from 2018 to 2020, and we established the nationwide monitoring system and secured a bridgehead for monitoring invasive insect pests passing the border including seven universities.

• Korean journal of applied entomology
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• v.31 no.1
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• pp.69-78
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• 1992

The extensive cultivation of new yielding varieties might give some distruption to the rice insect pest complex in Korea The population of Nephottetix cincticeps and Laodelphax striatellus has decreased in number since the extensive cultivation of new varieties, Tongil lines, in 1976. During the last 23 years, the rice insect pest population except for Chilo suppressalis drastically decreased, however, C. suppressalis population increased again in recent years. This tendency seems to be very closely correlated with the cultivation of new varieties, and a lot of fertilizations and insecticides applications.

• Mycobiology
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• v.49 no.3
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• pp.275-279
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• 2021

A fungus of the genus Kordyana, found on leaves of Commelina communis and C. minor exhibiting white smut-like symptoms, was identified as Kordyana commelinae based on morphological characteristics and two rDNA sequence analyses. We report the novel occurrence of the genus Kordyana in Korea and the association of K. commelinae with the host plant species. As well, we provide the necessary mycological information to resolve species delimitation and taxonomic problems of Kordyana.