• 농업기술회보
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• v.41 no.2 s.486
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• pp.30-34
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• 2004

• Korean journal of applied entomology
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• v.35 no.3
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• pp.243-248
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• 1996

This study was conducted to select the acaricides selective to H. axyridis and examine the effects on phytophagous mites and natural enemies after application of selected acaricides in the apple orchard. All the acaricides tested were more toxic to T. urticae and P. ulmi than to H. axyridis, and also were more toxic to egg than to the larva and adult of H. myridis. Azocyclotin and fenpropathrin were the highest and lowest selective acaricides to H. axyridk, respectively. The density of phytophagous mites was high affected by frequency of acaricide application. Significant difference in the changes of the density of natural enemies was not be observed according to frequency of acaricide application and kinds of acaricide. Acaricide treatment showed high effect on the population densities of A. womersleyi and Oriur spp., while less effect on Chrysopa spp.

• Korean journal of applied entomology
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• v.29 no.2
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• pp.104-112
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• 1990

Studies were conducted to investigate hosts, life cycle, population dynamics and natural enemies of mulberry scale, Pseudaulacaspis pentagona Ta. & Tozz., from 1987 to 1988 in southern region of Korea. The host plants were 22 families and 74 species. Host plants belonged to genus Prunus in general were severely damaged due to mulberry scale. Mulberry scale was most likely to have three generations a year with first occurrence of larval stage from mid-May to late June, second occurrence from mid-July to mid-August and third occurrence from early September to late October including 3 peaks in early and mid-June, late July and mid-September. In case of each stage occurrence, eggs were peaked on 10th day, larvae on 25th day and adults on 7th day from beginning of occurrence, respectively. Natural enemies were observed as parasitoids of 3 species such as Aphytis diaspidis, Archenomus orientalis and Apterencyrtus mocrophagus and as predators of 3 species such as Chilocorus Kuwanae, Chilocorus rubidus and Hormonia axyridis. Shoot growth was affected by mulberry scale and Lepra to dwindle as much as half of normal growth.

• Korean journal of applied entomology
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• v.25 no.1 s.66
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• pp.37-40
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• 1986

We surveyed the IRRI farm to determine the extent of parasitization of yellow stemborer egg masses. The egg masses were randomly collected at weekly intervals from July to October 1984 from rice fields, 15-20 days after transplanting, and brought to the laboratory for collection of emerging parasites. Three species of hymenopterous parasitoids-Tetrasticus schoenobii, Telenomus rowani, and Trichogramma japonicum-were found from 700 egg masses. We introduced a method to calculate percent parasitism as based on parasite biology and behaviour. Among the three species, the combination of T. rowani and T. japonicum was the highest multiparasitization of yellow stem borer egg masses, and T. rowani, a solitary parasite had the highest number based on immature and adult stages counted. However, T. schoenobii may be the most efficient parasite because two to four host eggs are needed to complete the larval period, and it took $10{\sim}14$ days for one generation.

• Korean journal of applied entomology
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• v.29 no.3
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• pp.209-215
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• 1990

Some preliminary studies were conducted to find out whether the levee-burning could justifiable for the suppression of insect pests, particularly the smaller brown planthopper (Laodelphax striatellus F.). Density surveys on pests and their enemies (mostly spiders) were carried out upto the mid May at an experimental paddy field located in Suwon after of it's levee $(72\times1m)$ was burned on Feb. 20, 1987. Results were discussed in relation to density recovering of both pests and their possible enemies (spiders) and summarized as below. Not a single individual of any pest or enemy was found from the levee upto sometime after the levee-burning. Grasses started to grow more vigorously in burned ares than in unburned upto about 60 days after the burning. And densities of both pest and enemies grew higher in burned areas than in unburned from about 75 days after the burning (in Early may). It is suspected that all individuals of pests and enemies fond from the burned areas could have immigrated from the surrounding areas. If levee-burning was carried out in much wider areas, much longer time would be needed to recover the density of both pests and enemies to the center region of the burning. Wingless spiders would require even longer time than winged pest species to re-establish in the center region of the widely burned field. Pirata subpiraticus, the most abundant spider species in Korean paddy fields, starts to move about and searches for food at above $9^{\circ}C$ which is somewhat lower than the critical temperature for the pest species. Thus P. subpiraticus would require more food than other pest species early in the spring, and therefore, it would have lower probability to survive than pest species particularly in burned areas. Experiments for pest suppression with levee-burning would better be carried on in much wider areas, and its justification seems to be discussed after man other disciplines related to both pests and their natural enemies were throughly studied together with their density surveys. However, according to the present point of vie, the opinion that levee-burning is helpful for controlling pests which over winter on levee areas could not be justifiable.

• Korean journal of applied entomology
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• v.18 no.4 s.41
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• pp.149-152
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• 1979

The relative toxicity of some of the insecticides which have been used for the control of paddy rice insect pests in Korea was evaluated in the laboratory with the brown planthopper (BPH) Nilaparvata lugens, and a predaceous paddy spider Pirata subpiraticus. In order of the relative toxicity (LD5O value to spider/LD50 value to BPH) were PAP (0.4), MPP(0.1), MEP(1.8), diazinon(2.8), carbofuran(7.5), NAC(11.3), BPMC(17.5), Pyridaphenthion(35.9) and MIPC(65.7). MIPC and Pyridaphenthion were considered as having the desirable selective toxicity for the spider and the BPH.

• Korean journal of applied entomology
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• v.42 no.1
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• pp.81-84
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• 2003

Biological control of aphids using "banker-plants with the parasitoiid, Aphidius colemani Viereck (BPAC)" was carried out on cucumber in greenhouse. The BPAC consisting of barley seedlings infested with Schiraphis graminum (Rondani) enhanced the early establishment of Aphidius colemani in the greenhouse and prolonged the control of Aphis gossypii on May 8, 2001 The BPAC was placed in the greenhouse at transplanting at the rate of 1 per 30 m2 of cucumber. Although good control effect was gained until early August after placing banker plants on May 9, the effect after then because of high temperature. The aphid population on cucumber in control plots reached to a peak on June 26, and decreased because of entomopathogenic fungus for rainy season of July, and increased again to a very high population on August.

• Korean journal of applied entomology
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• v.42 no.2
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• pp.169-171
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• 2003

The life history and natural enemies of Coleophora obducia Meyrick which is a defoliating pest of Larix leptolepis were studied mainly in Chungchongbuk Province. Larix leptoiepis was the only host plant of this pest. Coleophora obducia had one generation per you and the adults emerged from mid May to late May with a peak emergence around May 14th. The mean number of eggs in an ovary was 44.5 and most females oviposited one egg on each needle. The duration of the egg stage was about two weeks. Larvae passed the winter in a pouch made by spinning the needles. Pupation began in the late April, and the pupal period was two weeks on average. The natural enemies observed were parasitoids and predators.

• Korean journal of applied entomology
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• v.62 no.1
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• pp.21-27
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• 2023

In this study, Nematus tibialis Newman, 1837 (Hymenoptera: Tenthredinidae), is firstly reported in South Korea. The manuscript provides diagnostic illustrations, diagnosis, color variations, development stages and distribution of N. tibialis.

• Korean journal of applied entomology
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• v.52 no.4
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• pp.379-386
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• 2013

Aphidius colemani and Orius laevigatus aree natural enemies of the control cotton aphid and western flower thrips, which are the major pests of cucumber plants. We evaluated the low toxicity of 47 fungicides against A. colemani and O. laevigatus, and we investigated the simultaneous effect of the natural enemies with fungicide of low toxicity on the pests. The toxicity of DBEDC, hexaconazole, pyraclostrobin, tribasic copper sulfate, triflumizole, chlorothalonil, flusilazole, folpet, carbendazim+diethofencarb, cymoxanil+fenamidone and trifloxystrobin to A. colemani mummies was more than 50% and to O. laevigatus was low toxic. Among the fungicides with low toxicity, azoxystrobin 20% WP was selected because it could be used simultaneously with A. colemani and O. laevigatus and as a fungicide to control powdery mildew and downy mildew. In 2011, the densities of western flower thrips and cotton aphid increased rapidly in early-May in Gongju and Cheonan, Chungnam Province. When azoxystrobin was used at an interval of 10 days in spring, A. colemani and O. laevigatus were released at an interval of 7 days at the early occurrence of the pests. The natural enemies decreased the densities of the pests; the maximum number of A. colemani mummies was 18 per lower leaf, and the maximum number of O. laevigatus was 0.5 per flower. Azoxystrobin did not influence the densities of A. colemani and O. laevigatus. The results show that the selected fungicides can be used with A. colemani and O. laevigatus for the intergrated pest management of cotton aphid and western flower thrips in cucumber polyvinyl house cultivation.