• 아시안잔디학회지
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• 제11권3호
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• pp.185-191
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• 1997

Biological control of turfgrass insect pest Blitopertha orientalis, forest insect pests, Agelastica coerulea, Meganola melancholia, and Glyphodes perspectalis,vegetable insect pests, Plutella xylostella and Agrotis segetum were conducted with entonopathogenic fungus, Metarhizium anisopliae J-22 isolated from black pine forest soil in Cheju province. Mortality of B. orientalis larvae was 53.3% at the rate of 3.4 $\times$ 1O 7 conidia /ml. A. coerulea and M melancholia larvae showed 100% mortalities at 9.6 $\times$ 106 conidia /ml and 2.7 $\times$ 10 7 conidia /ml as well. However, G. perspectalis larvae were not dead even at 4$\times$ 1O 7 conidia /ml. On the other hand, M anisopliae J-22 was effective against P. xylostella larvae showing 100% mortality at 4 $\times$ 10 7 conidia /ml. KEy words:Entomopathogenic fungi, Biological control, Metarhizium anisopliae, Pathogenicity,Blitopertha orientalis, Agelastica coerulea, Meganola melancholia, Glyphodes perspectalis,Plutella xylostella, Agrotis segetum.

• 한국작물학회지
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• 제27권4호
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• pp.361-370
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• 1982

The effects of climatic factors on organisms lire variable and complex, and it, however, can be interpreted in terms of those on the distribution and those on the population densities. The distribution of an organism may largely be determined by the temperatures, except some temporal organisms which are depended on the air mass movements. Population density of an organism is determined by various climatic factors, such as previous winter temperature, temperature of growing season and rainfall. The start of growing season of the rice plants has been shifted to earlier since last decade in Korea. This may mean that the overall climatic condition during the growing season might be considerably different from those in past years, and such a difference in climatic conditions might have close relation with the recent status of the diseases and insect pests through direct effects on the physiology and population dynamics of the organisms, as well as through on the biotic associations of the pest organisms. The white back planthopper and brown planthopper have become the key insect pests in Korea in recent years. They are migratory and have high reproductive pontentials and more generations than average residential insects. The synchronization of the migrants and physiological condition of the rice plants seems to be the important factors in relation to the recent outbreaks of these insects; the high reproductive rate can be obtained with the growth stage of rice being 30-50 days after transplanting. The modication of the microclimate associated with high plant density and some other introduced new cultural techniques also have some relation with the outbreak. The key diseases of the rice are the blast disease, sheath blight and the bacterial leaf blight. For the rice blast, the seedling blast and leaf blast during the early growing season and the neck blast, have become more serious, the former may be related to hotbed nursery and the later may be related to the high humidity in early August, and synchronization of the heading time which has been shifted to early part from middle or late part of August. In general, for the rice diseases, the development of the new races have been the most serious which are largely resulted from the introduction of the new varieties, but it also seems to be related with the prolonged periods of the favorable condition associated with the shifted growing seasons. In general, the diseases and insect pest problems have become much more variable and complex, and control measures should be based on the thorough knowledge of the ecology of the pest organisms, that is, effects of various environmental factors on the disease cycle; spore release, spore deposition, infection, colonization and sporulation of the disease organisms, and those on the development, reproductive potentials, dispersal, age specific responses of the insects. The well organized real-time pest management systems, such as alfalfa weevil management system developed at the Purdue University in U.S., is the prime importance for the implementation of the pest management principles.

• 한국환경농학회지
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• 제37권2호
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• pp.125-134
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• 2018

BACKGROUND: Green peach aphid (Myzus persicae) is an insect pest that significantly affects crop production. A number of pesticides have been used for aphid control, but their concerns on insect resistance and food safety have required alternative methods for pest management. In an effort to find for an alternative approach to aphid control, we screened plants extracts and examined their potentiality as insecticidal bio-resources. METHODS AND RESULTS: Two hundred and ninety eight plant extracts were examined for insecticidal activity against the aphid, and the best candidate among them was chosen for further study. The extracts from Cinnamomum camphora was determined to be the best candidate exhibiting insecticidal activity more than 60% at a level of $1,000{\mu}g/mL$. GC/MS analyses detected camphor, borneol, 4-terpineol, ${\alpha}$-terpineol and caryophyllene oxide as major compositions from the extracts obtained by hydrodistillation. Caryophyllene oxide exhibited the highest insecticidal activity with a $LC_{50}$ value of $237{\mu}g/mL$. Camphor lowered significantly the $LC_{50}$ value of caryophyllene oxide and increased largely its concentration in aphid, suggesting that camphor played a role in enhancing the insecticidal activity of caryophyllene oxide. CONCLUSION: This study suggested that camphor and caryophyllene oxide may be used as an insecticidal bio-resource for insect control against green peach aphid.

• International Journal of Industrial Entomology and Biomaterials
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• 제18권2호
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• pp.57-61
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• 2009

Three years($2004{\sim}2007$) survey was conducted on the incidence of silkworm diseases namely, Grasserie, Flacherie, Muscardine and Uzi fly, a silkworm pest with 150 sericulture farmers in the districts of Chittoor and Anantapur in Andhra Pradesh. The data revealed that grasserie and flacherie incidence were maximum in summer season and minimum in winter season whereas muscardine was observed high in winter season in both the areas and rarely in rainy season in Chittoor and Anantapur districts. An improvement of 11.16 and 7.6 kg cocoons/100 dfls were recorded in the batches of PM xCSR2 Diseases free layings(Dfls) reared in rearing houses disinfected with 2% bleaching powder and Ankush, a plant based bed disinfectant applied as per schedule, respectively. The Uzi fly incidence was suppressed by 61.02% in batches where the integrated package was adopted for control of Uzi fly infestation.

• 한국응용곤충학회지
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• 제47권3호
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• pp.273-286
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• 2008

해충방제를 위하여 천적을 사용하는 친환경농가에서 발생하는 해충을 친환경적인 종합적방제방법을 수행하기 위한 로드맵을 작성하였다. 먼저 친환경적인 방법으로 딸기를 생산하는 농가에 딸기 어린묘를 공급하는 육모장에서 발생하는 주요 해충으로는 점박이응애(Tetranychus urticae)와 목화진딧물(Aphis gossypii)이였다. 딸기를 생산하는 본 포장에서 발생하는 주요 해충들 역시 점박이응애와 목화진딧물이 가장 많이 발생하였다. 점박이응애의 생물적방제를 위하여 칠레이리응애(Phytoseiulus persimilis)를 방사하였고, 목화진딧물의 방제를 위하여는 콜레마니진디벌(Aphidius colemani)을 방사하였다. 그러나 천적의 방사로 점박이응애와 목화진딧물의 개체군을 억제할 수 없어, 살충제를 살포하여 해충 개체군 밀도를 낮춘 다음에 천적들을 다시 방사하는 전략을 구사하였다. 수확기인 동절기에 천적만을 가지고 해충을 방제하지 못하는 이유로는 밤낮의 일교차가 심하여 해충과 천적의 활동에 많은 영향을 주고 있기 때문이며, 이러한 환경은 해충보다는 천적에 더 많이 영향을 주는 것으로 보인다. 따라서 효율적인 친환경 종합방제로는 육묘장에서 해충의 유입을 차단하고, 본포에 정식 후에는 천적을 방사하여 해충 발생 초기부터 해충을 제어해야 되며, 천적의 활동이 둔해지는 혹한기에는 천적에 독성이 적은 선택성 살비제와 살충제 등을 사용하여 해충 개체군을 억제할 필요가 있다. 그 후에는 다시 천적을 방사하여 해충 개체군을 조절하는 방법을 택하여야 한다.

• Natural Product Sciences
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• 제23권4호
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• pp.235-238
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• 2017

Colorado potato beetle is a most destructive insect pest of potato throughout the world. Although utilization of chemical insecticides is a main method for management of this pest, their negative side-effects such as threat to humans and the environmental pollution prompted researchers to search for natural alternatives. Recently plant essential oils with low or without side-effects against noun-targeted organisms and with high availability were considered as safe bio-pesticides. In the present study, toxicity of essential oil of Iranian lemongrass, Cymbopogon citratus Stapf, was evaluated against 3th instar larvae and adults of Colorado potato beetle by a leaf dipping method. Results displayed essential oil had notable toxicity against both larvae and adults after 24 and 48 h exposure times. Probit analysis revealed $LC_{50}$ values (lethal concentration to kill 50% of population) with 95% confidence limits were 10.32 (9.17 - 11.72) and 7.76 (6.80 - 8.74) ${\mu}l/ml$ for larvae and 6.27 (4.82 - 8.15) and 4.35 (3.24 - 5.62) ${\mu}l/ml$ for adults after 24 and 48 h, respectively. Based on regression analysis, a positive correlation between log concentration of essential oil and insect mortality was achieved. Results indicated C. citratus essential oil can be candidate as a natural alternative to the harmful chemical insecticides in the management of Colorado potato beetle.

• 한국균학회지
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• 제37권2호
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• pp.139-143
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• 2009

Several entomopathogenic fungi have been exploited to be developed into biological control agents in insect pest management. The beet armyworm, Spodoptera exigua, is a serious insect pest infesting various crops, but not effectively controlled by commercial chemical pesticides due to its high insecticide resistance. A fungal isolate was isolated from S. exigua larvae collected from cabbage field in Andong, Korea. The fungus could be cultured in potato dextrose agar. Larvae of S. exigua injected with the cultured conidia showed a potent entomopathogenicity. To identify the fungus isolate, its internal transcribed space (ITS) and surrounding partial 18S/28S regions were sequenced. The ITS sequence was highly matched (99%) to that of Nomuraea rileyi. Morphological characters of its hyphae and conidia were well fit to those of known N. rileyi. This study reports the first record of an entomopathogenic fungus, N. rileyi, in Korea.

• International Journal of Industrial Entomology and Biomaterials
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• 제10권2호
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• pp.137-141
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• 2005

Though many insecticides are commercially available, development of resistance, pest resurgence and effects on non-target organisms led to the search for alternate insect pest management (IPM) strategy based on larval growth and reproductive fitness. Reproductive potential of insects depends on its acquiring of vitellogenic competence which is under hormonal control. Exogenous application of analogues of JR (JHAs) and ecdysterone could derail normal development and reproduction in insects by manipulating an array of physiological processes. In the rice pest, brown planthopper, Nilaparvata lugens, JHA, hydroprene induced metathetely from the fifth (final) instar nymphs in an age-dependent manner. Day 0 of the final instar showed highest sensitivity to induce this abnormal development. Adults emerged from treated day 3 nymphs looked normal. Both the morphotypes were reproductively incompetent and showed partial to complete sterility. Pre-adult exposure of the ovarian tissue to hydroprene suppressed mitotic division of germinal cells and induced abnormalities in the later s1ages of growth and differentiation of ovary in N. lugens. More over the nymphal exposure to hydroprene inhibited patency changes of follicular epithelium and affected competence of the follicles for yolk sequestration. In the absence of ovarian growth and oocyte differentiation, germarium found disintegrated, trophic core regressed and terminal oocytes resorbed. Hydroprene exposure to newly ecdysed brachypterous females did not affect ovarian development and egg production. Proper larval-adult transition appeared as a. prerequisite for vitellogenic competence in N. lugens for which the ovarian tissues must be exposed to ecdysterone in the internal milieu devoid of JH.

• 한국미생물·생명공학회지
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• 제27권5호
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• pp.415-418
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• 1999

Thecodiplosis japonensis is an important insect pest in pine trees and hard to be controlled by chemical pesticides due to its characteristic life cycle. Experiments were conducted to determine the pathogenicity and growth temperature of several entomopathogenic fungi as potential microbial insectcides for T. japonensis. Beauveria bassiana SFB-SC and Paecilomyces fumosoroseus SFP-198 were highly pathogenic against T. japonensis. B. bassiana SFB-SC had also pathogenicity against a beneficial insect Bombyx mori. Growth rate and pathogenicity of P. funmosoroseus SFP-198 under 15$^{\circ}C$ was higher than those of B. bassians SFB-SC. These results indicated that P. fumosoroseus SFP-198 is a potential microbial control candidate for control of T. japonensis.

• 한국유기농업학회지
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• 제22권2호
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• pp.269-280
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• 2014

본 연구는 고삼, 정향 및 neem 추출물에 대한 항균 항충력을 규명하여 벼 친환경 재배 포장에서 병해충 방제제로의 이용가능성을 검토하고자 수행하였다. 식물추출물에 대한 잿빛곰팡이균에 대한 항균력 실험결과 정향추출물이 가장 높은 활성을 나타내었으며, 벼멸구에 대한 살충력은 고삼추출물이 가장 높은 효과를 보였는데, 고삼추출물의 300배 희석용액에서도 100%의 살충 방제가를 나타내었다. 정향과 고삼추출물에 각각 목초액(10%)과 유화전착제(10%)를 혼합하여 친환경 벼 재배포장에 살포하고 병해충 발생률을 조사한 결과, 정향추출물 처리구의 병해 방제가는 무처리구(100%) 대비 50.8%, 해충 발생은 70.6%를 나타내었고, 고삼추출물 처리구는 무처리(100%) 대비 병해 방제가는 43.1%, 해충 방제가는 79.1%로 나타났다. 결론적으로, 고삼 및 정향 추출물은 벼 친환경 재배 시 병해는 약 50%, 충해는 약 70%를 감소시킬 수 있어서 친환경농자재로의 활용 가능성을 확인하였다.