• Korean journal of applied entomology
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• v.47 no.1
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• pp.75-86
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• 2008

Many kinds of environment friendly agricultural materials (EFAMs) were used for the plant protection, furthermore they support the growth of crops in the greenhouses and the kindly environment friendly farming. Natural enemies might be used for control of insect pest with EFAMs at the same space and time. For testing the toxicity of EFAMs against to natural enemies, 10 EFAMs were selected and tested in small greenhouses and farm's fields. In case of Harmonia axyridis larva, there was no predacious activity against cotton aphids in the block with EFAMMo L, EFAMPE D, EFAMME G and EFAMAE A, otherwise, aphid population was rapidly decreased in the control block without EFAMs. Both of Trialeurodes vaporariorum and Encarsia formosa population were slightly decreased in the block with EFAMs. There were significantly decreased in the block with IEFAM C, FEFAM D, EFAMSM Band EFAMPE D compared with control area. Especially, there was significantly maintained a very low population, both T. vaporariorum and E. formosa in the block with EFAMMo C. The parasitized ratio of Aphidius colemani is also very low in the block with EFAMs compared with control area. In the block with IEFAM C, FEFAM D, EFAMPE D and EFAMMo L, there were significantly different with control area in the number of mummies. Otherwise, in case of Diglyphus isaea and Liriomyza trifolii, there was no significantly different between blocks with and without EFAMs. In the block with EFAMMo C, Tetranychus urticae and Phytoseiulus persimilis populations were significantly maintained a very low level. However, the population of T. urticae was increased, but P. persimilis was decreased in the block with EFAMMo L.

• The Korean Journal of Ecology
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• v.22 no.5
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• pp.287-294
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• 1999

During the period from April to October, 1998 the authors investigated the gall development process of Chinese gallnuts (Schelchtendalia chinensis) on sumac (Rhus javanica) at Mt. Goduk near Chonju city in Chonbuk province. The majority (56.8%) of chinese gallnuts were formed on first pinnates and 24.3% on second pinnates of sumac leaves. Galls began to form from the 1st of June and grew slowly until the 24th of June. Galls enlarged rapidly after the 1st of August, but their growth rates decreased after the 26th of August and stopped growing after the 8th of September. Alate viviparous females escaped from galls after the 24th of September. Fundatricies, the second generation in the galls, exuviated three times to become adults on the 24th of June. Fundatrix adults bore 1∼10 eggs in the body and laid 1∼16 nymphs of the second generation. Nymphs of the second generation began to appear on the 17th of June and had matured completely on the 14th∼24th of July. Adults of the second generation bore eggs in the body. Thus the developmental period of the second generation was 27∼37 days. Nymphs of the third generation appeared on the 14th of July and finally alate viviparous females were developed on the 24th of September. During the two months from the beginning of the third generation to the appearence of the final alate viviparous females, there should be at least two generations, that is, the third and fourth generations. The fourth generation seems to begin at about the 20th August because the number of inhabitants (2,859 individuals) in galls on the 26 th of August had increased more than 10 times those (263 individuals) on the 19 th of August. The tannin content of galls was 65.04∼68.23% while that of sumac leaves and stems was 11.56%, 3.49% respectively.

• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.568-578
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• 2019

The nymphal development of the potato aphid, Macrosiphum euphorbiae (Thomas), was studied at seven constant temperatures (12.5, 15.0, 17.5, 20.0, 22.5, 25.0, and 27.5±1℃), 65±5% relative humidity (RH), and 16:8 h light/dark photoperiods. The developmental investigation of M. euphorbiae was separated into two steps, the 1^st through 2^nd and the 3^rd through 4^th stages. The mortality was under 10% at six temperatures. However, it was 53.0% at 27.5℃. The developmental time of the entire nymph stage was 15.5 days at 15.0℃, 6.7 days at 25.0℃, and 9.7 days at 27.5℃. In the immature stage, the lower threshold temperature of the larvae was 2.6℃ and the thermal constant was 144.5 DD. In our analysis of the temperature-development experiment, the Logan-6 model equation was most appropriate for the non-linear regression models (r²=0.99). When the distribution completion model of each development stage of M. euphorbiae larvae was applied to the 2-parameter and 3-parameter Weibull functions, each of the model's goodness of fit was very similar (r²=0.92 and 0.93, respectively). The adult longevity decreased as the temperature increased but the total fecundity of the females at each temperature was highest at 20℃. The life table parameters were calculated using the whole lifespan periods of M. euphorbiae at the above six temperatures. The net reproduction rate (R₀) was highest at 20.0℃(63.2). The intrinsic rate of increase (r_m) was highest at 25℃(1.393). The finite rate of doubling time (D_t) was the shortest at 25.0℃(2.091). The finite rate of increase (λ) was also the highest at 25.0℃(1.393). The mean generation time(T) was the shortest at 25.0℃(9.929).

• Korean journal of applied entomology
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• v.25 no.2 s.67
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• pp.113-120
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• 1986

Soybeans collected from different locations in Korea were planted for tests of seed transmission of soybean mosaic virus (SMV). The percentage of seed transmission ranged from 20.5 to 29.5% in 14 seedlots including soybean cultivar Namhe and 12 to 19% in other 44 seedlots. However, no seed transmission of SMV was observed in soybean cultivar Younkiyongho. SMV was detected from embryo and cotyledon of soybean seeds. The infection of SMV was highly detected from premature seeds than from fully mature seeds, and higher from seeds harvested from plants infected before June 20 than plants infected around July 20 and August 20. No significant relationship was observed between seed transmission of SMV and mottling of seeds. The incidence of soybean mosaic disease followed by one month after peak of aphid population. The number of aphids was less on leaves of soybeans with short and dense trichomes whereas it was higher on leaves of soybean with long and sparse trichomes. Generally, the number of aphids was decreased on leaves with long and dense trichomes as the growth progressed. Soybean cultivar Columbus and 14 cultivars were susceptible, Chief and 14 cultivars were moderate, but Jangbaek and 17 other cultivars were resistant to SMV when inoculated with one isolate of SMV.

• The Korean Journal of Pesticide Science
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• v.4 no.3
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• pp.19-26
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• 2000

In order to select potent bioactive isolates, 70 Fusarium isolates obtained from soil and 21 plant species were screened by antifungal, insecticidal, herbicidal, and duckweed bioassays after culturing in potato dextrose broth and rice solid media. Eight (11.4%) of the 70 liquid broth cultures showed disease-controlling activities more than 80% against at least one of the 6 plant diseases tested. Fusarium sp. FO-68 isolate exhibited the most potent antifungal activity; it controlled rice blast, wheat leaf rust, and barley powdery mildew with control values more than 95%. Out of 70 solid cultures, 21 (30.0%) controlled at least one plant disease more than 80% and F. equiseti FO-68 isolate showed disease-controlling activities more than 95% against 3 plant diseases such as rice blast, tomato late blight, and wheat leaf rust. As for tile insecticidal activities, 2 liquid and 1 solid cultures showed potent insecticidal activities against pest insects more than 80%, Liquid cultures of F. oxysporum FO-61 and Fusarium sp. FO-80 isolates exhibited insecticidal activities more than 80% against green peach aphid and diamondback moth, respectively. The solid culture of Fusarium sp. FO-510 isolate had 80% insecticidal activity against green peach aphid. However, none of liquid and solid cultures of the 70 Fusarium isolates showed potent herbicidal activities against 10 upland weeds. As the results of duckweed assay, 3 liquid cultures showed 70% growth inhibitory activity at concentrations less than 1.25% of culture supernatants and 9 solid cultures had a potent inhibitory activity against duckweed growth. On the other hand, there was a significant correlation between antifungal activities and herbicidal activities against duckweed of both liquid and solid cultures of tile 70 Fusarium isolates.

• Korean journal of applied entomology
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• v.58 no.2
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• pp.151-157
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• 2019

It was available to store both nymphs and adults of Geocoris pallidipennis at $5^{\circ}C$ for 3 weeks without negative effects on their survival, fecundity, and Bemisia tabaci predation. Fecundities of G. pallidipennis showed the tendency to be decreased with increasing cold storage duration, but up to 4 weeks, storage at $5^{\circ}C$ didn't affect their fecundity. When Micromus angulatus adults were stored at $5^{\circ}C$ with honey solution as preys, it was possible to store up to 140 days showing approximately 50% of cumulative survival, but over 2 week cold storage was not suitable for their fecundity. With the increase of cold storage duration, the aphid predation by M. angulatus decreased, but it could be possible to cold store until 5 weeks without any significant effect on their aphid predation. Thus, short term cold storage of G. pallidipennis and M. angulatus could be useful for inundative biological strategies.

• Korean journal of applied entomology
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• v.18 no.2 s.39
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• pp.101-106
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• 1979

Present studies were carried out to get a basic information for biological control of soybean rod borer, Grapholitha glycinivorella Matsumura, causing main injury in soybean cultivation in Korea. 1474 native strains were cultivated in field to evaluate the pod borer damage. Pubescence density and color, maturity group, seed coat color, aphid and general leaf damage and seed damage by pod borer were investigated, and determined among their relationships. As another basic study for ecological control of insect, 6 leading varieties were planted on different planting date with 3 levels of plant spacing, on which pod borer damage and some related agronomic characters were studied. The results obtained one summarized as follows: Average injury of soybean pod borer was $5.2\%$ ranging $0-38\%$ in 1474 strains planted on 20 May. Non-significant correlations were found between pod borer damage and pubescence density and color, while pod borer damage closely related with maturity groupand aphid damage at $5\%$ level ofttests. Most severe damage was found in green seed coast color and maturity group V. Late and sparse plantings tend to have more damages to the pod borer than those of early and dense plantings. Pod setting date and period of pod maturing seemed related with pod borer damage. Bongeui and Chungbuk-baik cultivars were resistance to soybean pod borer, while Clark and Kumkang-daerip were susceptible in field tests.

• Korean journal of applied entomology
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• v.48 no.3
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• pp.319-325
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• 2009

Woolly apple aphid, Eriosoma lanigerum, overwintered as adult or nymph stage on rootstocks, and crown- and root sucker in the soil. In an un sprayed apple orchard, the number of E. lanigerum colony started to increase from mid-April, showed the 1st peak between late June and early July, thereafter decreased followed by the 2nd peak in late July, and then again peaked in late September as the size in the 1st peak. In this orchard, the number of E. lanigerum colonies per tree did not exceed 3.5 colonies during the peak occurrence period, and was maintained around 2 colonies throughout seasons. In all seasons, parasitism of Aphelinus mali on E. lanigerum was much lower on root colonies than on aerial colonies that located on shoots and tree trunks above the ground. The parasitism of E. lanigerum was high in most orchards examined, showing parasitism of > 70% in maximum in most cases. In the laboratory bioassay for the mortality effects of several insecticides on E. lanigerum, fenitrothion, dichlorphos, machine oil, methidathion, thiacloprid, and imidacloprid showed 97.8, 96.8, 95.4, 91.5, 26.7, and 7.8% morality, respectively. Also, the adult emergence rates from A. mali mummies were 51.2, 72.6, 14.2, 3.5, 72.2, and 85.4% in the treatment of the above insecticides, respectively. Insecticides belong to neonicotinoid, which are newly developed to control aphids, showed low mortality against E. lanigerum. Fenitrothion and dichlorphos were effective on E. lanigerum control and had a low toxic to A. mali. Consequently, the insecticides should be useful in integrated pest management system for E. lanigerum in apple orchards.

• Korean Journal of Medicinal Crop Science
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• v.1 no.1
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• pp.74-80
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• 1993

Survey on the status of cultivation and production of medicinal crop was studied on 18 medicinal herbs and 5 medicinal trees in 66 major crop producing complexes. Native seeds or seedlings of the crops obtained from self-seed or neighbored farmer were cultivated and organic fertilizer was preferred to chemical fertilizer in the complexes. More than 60.7% of farmers were applied compost among the organic fertilizers, while 34.8% of them cultivated without any organic fertilizers. Both of using the compound chemical fertilizers and urea and urea only used were showed 51. 5% and 40.9%, respectively. Ostericum koreanum, Angelica gigas, Phellopterus littoralis, and Bupleurum fulcatum belonging to the family Umbeliferae and Aralia continentalis, Polygonatum sibiricum and Eucommia ulmoides in the complexex were not damaged by insect pests and plant diseases. Mite, aphid, grub, cutworm, onion magot fly and european corn borer were known to as major insect pests and anthracnose, powdery mildew, brown leaf spot, leaf blight and root rot as major plant diseases. Productivity and income of a farm by medicinal crops in the complex were greatly different from seeding time, planting distance, year yielded, and selling routes even in the same cultivation method and in the same cultivated area.

• Korean Journal of Medicinal Crop Science
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• v.15 no.3
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• pp.199-202
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• 2007

This study was carried out to provide pest control information for the cultivation of Eleutherococcus senticosus Max. As a result of investigation of the diseases and insect pests, three pathogens and three insect pests were identified from the field sample, respectively. The identified insects pests were aphids, stinkbugs and Bothrogonia japonica. Occurrenre peaks of aphids were occurred on June and August, and generally young leaves and flower buds were injured mainly. The identified diseases were black ring spot caused by Phoma sp., gray mold caused by Botrytis cinerea and leaf blights caused by Rhizoctonia solani. The black ring spot was the most severe disease and was investigated from the beginning of June, and the incidence of the disease was 30% higher than that on September. As a result of growth test under different temperature conditions on PDA, these pathogens showed the best mycelial growth rate between 25 $^{\circ}$C and 30 $^{\circ}$C, and these results indicate that these diseases occur on hat summer season.