• Korean journal of applied entomology
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• v.42 no.2
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• pp.133-138
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• 2003

To establish the successive rearing of red-striped golden stink bug, Poecilocoris lewisi Distant, developmental characteristics, host plant and oviposition preference were investigated. Raw peanuts were supplied to the insect as a substitute food at 25$\pm$$1^{\circ}C$, 60$\pm$5% R.H. and under 16Lㆍ8D photo regimen. Total developmental period was 48 days: 8.2$\pm$0.4, 5.4$\pm$0.2, 8. $\pm$0.5, 6.4$\pm$0.4, 7.4$\pm$0.3 and 12.6$\pm$0.8 days for egg, first though fifth instar, respectively. The instar survival rate was 57.1% and the sex ratio was estimated to be 53 : 47 (male : female). Adult longevity was on the average 30.8 in male and 35.4 days in female, respectively. Egg of P. lewisi was globular ($\phi$1.8-1.9mm) with milky white in color The number of eggs oviposited per clutch was mostly 14. Pre-oviposition period was 25.8 days and mean frequencies of oviposition were 4.4. Female preferred to oviposit on the host plant when available, but oviposited on the artificial leaf successively when the host is not around. On the other hand P. lewisi preferred to suck the nectar of stem or fruit of Phellodendron amurense Ruprecht, Zanthoxylum schinifolium Siebold et zuccarini, Cornus officinalis Siebold et zuccarini and Cornus controversa Hemsley among the 18 plant species tested.

• Korean journal of applied entomology
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• v.49 no.4
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• pp.325-331
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• 2010

Attractiveness of stink bugs to various colors, heights and locations of fish-net traps incorporated with aggregation pheromones was determined. Bean bug, Riptortus pedestris Fabricius, was most attracted to yellow color trap, followed by white, black, green, blue and brown. R. pedestris and one-banded stink bug, Piezodorus hybneri Gmelin, were most attracted to fish-net traps placed 80 cm above the ground regardless of sexes of two species of stink bugs. Between the sexes, however, R. pedestris females were more attracted to 40 and 80 cm above the ground than the males at those heights although the attraction was not significantly different at 120 and 160 cm heights. P. hybneri females tended to be attracted to 40 and 80 cm height traps but the attraction was the opposite at 120 and 160 cm heights. The highest attraction of R. pedestris was observed in a perilla field with no significant difference in the soybean field and border area in which no crop were cultivated between the perilla and soybean fields. R. pedestris was also more attracted to the sweet persimmon orchard than the soybean and medicinal crops fields, which was a significant difference between the two fields.

• Korean journal of applied entomology
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• v.20 no.3 s.48
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• pp.135-145
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• 1981

Vegetables including Chinese cabbage and radish have been grown in alpine areas such as Muju, Namweon, Jinan and Jangsu during the shortage period of vegetables. The incidence of various diseases, environmental factors such as temperatures and rainfalls, and aphid populations as virus vector were observed at 10-day intervals from July to September in those areas. Disease incidence showed no significant difference among locations. Major diseases in Chin ese cabbage were bacterial soft rot, white spot, downy mildew, mosaic virus, Alternaria leaf spot and Fusarium seedling blight. Major diseases in radish were virus, white rust, black rot, root rot, leaf spot and Fusarium seedling blight. Disease incidence reached peak on Aug. 20 with $27\%$ infection in radish and with $20\%$ infection in Chinese cabbage during the growing season, and declined thereafter. Percentage of infection in each growth stage showed $25\%$ at root thickening stage and $26\%$ at the harvest time in radish; and the head formation stage, $24\%$ at the harvest time. The data indicate that disease incidence in radish increased rapidly at late growing stage and progressively increased in Chinese cabbage Seedling blight caused by Fusarium sp. and root rot caused by Aphanomyces sp. were also observed in those areas. Cool and wet weather appeared to be favorable for disease incidences during the rainy period of growing season although average temperature was about $25^{\circ}C$. Populations of aphids were lower in the alpine vegetable growing area than that of flat areas. Aphids as virus vectors from total aphids collected were $73.5\%$ or 289 virus vectors /993 total aphids in Namweon and $18.1\%$ or 31 virus vectors/171 total aphids in Muju. The most prerevalent species of aphids was Myzus persicae Sulz.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.2
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• pp.191-195
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• 2002

In previous reports the authors have screened the inhibition effects of marine algae extracts on halitosis, and demonstrated that a brown algae, Eisenia bicyclis (' Daehwang') possess not only strong deodorant effect bug also considerable anticariogenic activities. In this study, we screened antibacterial effects of various marine algae, and measured minimum inhibitory concentration (MIC) value of them against mutans streptococci in vitro. Among the 27 species of marine algae, $80\%$ ethanol extract of dried sea-mustard, Laminaria japonica ('Dasima') showed the strongest inhibition activity against Streptococcus mutans KCTC 3300. The extracts of Ulva lactuca ('Galparae'), Codium fragile ('Cheonggak'), Ecklonia cava ('Gamtae'), E. stolonifera ('Gompi') and Undalia Pinnatifida ('Miyeok') showed slightly weaker inhibitory potency than L. japonica. Differences of MIC values in $80\%$ ethanol extract of some species of marine algae were observed depending on test bacterial species, i.e., S. mutans KCTC 3300 or S. sobrinus KCTC 3307. Eighty percent ethanol extract of dried L japonica was fractionated with diethyl ether, chloroform, ethyl acetate, n-buthanol and water successively, The ether-soluble fraction had inhibitory effect on S. mutans KCTC 3300, however the inhibitory effects were not found in the other fractions. The MIC values of $80\%$ ethanol extract and ether fraction were 180 and 105 $\mu$g/mL respectively, while no significant inhibition activity of water-soluble fraction was found even when the fraction was added up to 5,500 $\mu$g/mL.

• Korean Journal of Organic Agriculture
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• v.19 no.3
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• pp.357-372
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• 2011

We carried out the experiment to select the suitable sprout soybean varieties for environment-friendly cultivation in paddy field of southern part area, compares of excess moisture injury degree and yield ability among 29 sprout soybean varieties. Plant growth of sprout soybean was generally low in beginning and recovered after flowering due to rainfall. In paddy field cultivation, number of pod per individual and number of seed per individual were less in difference than upland cultivation, and maturing date was delayed 5-14 days than upland cultivation in most species. When environment-friendly cultivation, pest injury was not caused major problem for the growth during the vegetative period of soybean due to ground spider as natural enemy to insect pest. However, damage of stink bugs showed severe during grain filling period, and Dawonkong, Anpyeongkong, Dachaekong and Wonhwangkong showed susceptible to sting bug. SMV infection was weak and showed some necrosis symptoms in Sokangkong, but black root rot was not infected at all. Bacterial pustule began to be infected slowly from pod enlargement stage in most species, displayed severe symptoms in Dawonkong, Pungsannamulkong, Seonamkong and Sobaeknamulkong. The symptoms of pod anthracnose, pod blight and purple spot were greatly appeared after flowering. Disease resistance varieties was Paldokong, Kwangankong, Doremikong, Somyeongkong, Pungsannamulkong, Iksa-namulkong, Seonamkong, Sojinkong, Pureunkong, Bosugkong, Namhaekong and Sorokkong. Lodging index showed 3 in Saebyeolkong, and other species displayed slight lodging in 0-3 degree. 100-seed weight is 9.8-17.2g extent and increased 0.1-3.7g than upland cultivation in most species, but decreased in some species. Government purchase standard, species correspond to small-seed-size namulkong (Sizing screen diameter 4.0-5.6 mm) was Dawonkong, Dachaekong, Bosugkong, Seonamkong, Sokangkong, Hannamkong, Somyeongkong and Wonhwangkong. Species which seed yield was higher than Pungsannamulkong (266kg/10a) were Sorokkong, Hannamkong, Bosugkong and Sowonkong. Considering sprout soybean species, disease endurance, insect resistance, lodging resistance, 100-seed weight, yield ability and excess moisture tolerances synthetically, Seonamkong, Hannamkong, Doremikong, Bosugkong, Pungwonkong, Kwangankong, Sowonkong, Dagikong, Paldokong, Eunhakong and Pungsannamulkong were promising for environment-friendly cultivation in paddy field.

• Applied Biological Chemistry
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• v.13 no.3
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• pp.243-256
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• 1970

Nowadays, the damages caused by molds in cotton textile goods becomes influential. In our country, however, the relations between cotton goods and molds are not investigated and studied in detail. Two hundred and fifty seven kind of mold's samples were collected in ninety places through the whole country. The molds samples are mainly gathered according to each regions and seasons from molded cotton textiles. Out of this samples, we isolated six hundred and seventy two strains of molds and the results of isolation are following. 1. The distributed molds were Aspergillus sp., Rhizopus sp., Penicillium sp., etc. among them Aspergillus sp. were most widely distributed, and next were Rhizopus sp., Penicillium sp. etc. 2. The distribution of Aspergillus sp. abounded peculiarly in the dry season, while Rhizopus sp. in the rainy season. 3. The C.M.C, descomposing enzymes forming activity on molds were greatly concerned with intensity damage of cotton textile goods. 4. The formation of C.M.C. decomposing enzyme was only influenced by physiology of each strains. 5. Regarding to the growth. a. The molds which were saprophyting on the cotton textile goods were indicated vigorous growing. b. Among isolated six hundred and seventy two strains, there were above a hundred strains which produced pigment and nearly half of them fifty nine strains were Aspergillus sp. 6. Twenty one strains in isolated six hundred and seventy two strains were indentified which can heavily damage upon cotton textile. As a results of indentification of the selected strains, the following species was abtained, Aspergillus sydowi, wentii, niger, luchuensis, flavus, fumigatus, nidulans, Penicillium frequentants, roqueforti, chrysogenum, albicans, Rhizopus oligosporus, delemar, Mucor rouxii, mucedo, Neurospora sitophila, Monilia variabilis, fructigena, Cladsporium hurbarum and Aspergillus spp. Mucor spp.

• International Journal of Industrial Entomology and Biomaterials
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• v.4 no.2
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• pp.83-91
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• 2002

The protection of silkworm and its host plants from various kinds of pests parasite and predator is a chronic problem in sericulture. Silkworms and its primary food plants are heavily damaged by large number of pest. The major pests of primary tasar food plants (Terminalia arjuna and Terminalia tomentosa) are the gall insect (Trioza fletcheri minor). Various species of aphids (Eutrichosiphum sp.) have been recorded to damage oak tasar food plants whereas muga silkworm host plants (Machilus bombycina and Litsaea polyantha) are generally attacked by stem bores (Zeuzera multistrigata). Castor (Ricinus communis) is one of the primary host plant of eri silkworm and extensive damage is caused by the castor white fly (Trialeurodes ricini). Insects pests are major enemies of silkworms. Parasites (Blepharipa zebina, Exorista bombycis, Apateles glomeratus), predators (Canthecona furcellata, Sycanus collaris, Hierodulla bipapilla), wasps (Vespa orientalix) and ants (Oecophylla smargdina) continues to cause damage to silk industry. It is estimated that the losses due to parasites and predators are to an extent of 15-20 percent and varies from crop to crop. The complexities in the behaviour and life cycle of pest population existing in semi ecosystem warrant a special attention for their effective management specially in changing scenario for our modern sericulture. Though use of synthetic insecticides has provided us with effective control of almost all major pests and predators, yet their undesirable side effects limit their continued use. Biological control is one of the most important method which can be used to control the pests, parasites and predators population in sericulture. Various potential parasitoids, which can be utilized as an agent of biological control in sericulture have been screened. The natural enemies of the uzi fly (E. bombycis and B. zebina ) are already present in the nature. Nesolynx thymus, Trichria sp., Splangia endius, Dirhinus sp., Trichopria sp., Trichomalopsis apanteloctena and Pediobius sp. are the major parasitoids effective against uzi fly pupa. The scelionid Psix striaticeps and Trissolcus sp. are the Potential egg Parasitoids against stink bug (Canthecona furcellata). Various other native natural potential parasitoids have been screened and suitable strategies have been developed to check the population of pest insect in sericulture.

• Korean journal of applied entomology
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• v.60 no.4
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• pp.463-471
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• 2021

As a tropical plant, the neem tree (Azadirachta indica) has been used for a long time for disease and pest control and medical purposes. In this paper, we reviewed for the active ingredient of neem, the mode of action of azadirachtin in terms of insect growth regulation, repellent, feeding inhibition and oviposition against plant pests. And also we reviewed the current status of practical use in Korea. Among 57 products of neem-based eco-friendly organic agricultural materials distributed in Korea, seven products were certified for their efficacy. The average azadirachtin content of the seven products was 0.38%, which was 5.5 times less than the average content of 2.1% distributed worldwide. In the control effect on neem products in Korea, it showed some variation on aphids, but most showed a control effect of more than 90%. The treatment effects of Lycorma delicatula nymphs were 73-77%, and the control effects for thrips were obtained in the range of 50-72% mortality. The mortality effects against bug and moth species were generally low. It is expected that this review would provide important information necessary for the understanding of distributed neem products and the interpretation of experimental data.

• Korean journal of applied entomology
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• v.48 no.1
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• pp.37-44
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• 2009

This study was carried out to survey the occurrence of stink bugs and pecky rice grain caused by the stink bugs in paddy fields in six districts of Gyeonggi-do. In the levee of the paddy fields, 30 species of the stink bugs were collected, and the dominant species were Paromius exiguus in Hwaseong and Siheung, and Stenotus rubrovittatus in Pyeongtaek, Icheon and Paju. In the paddy fields, 23 species were collected, and the dominant species were Paromius exiguus in Siheung, and Stenotus rubrovittatus in Pyeongtaek, Icheon and Paju. P. exiguus overwintered and proliferated mainly in the west coastal region, where its host plants, Imperata cylindrica and Calamagrostis epigeois, were abundant, and then moved to paddy fields later in the season, resulting in the peak density in September in paddy area. Stenotus rubrovittatus and Cletus punctiger were abundant in paddy area in August and September, and Eysarcoris aeneus was abundant in June and July. When the stink bugs were inoculated on the rice, the rate of pecky rice caused by E. aeneus and P. exiguus at milk ripe stage was 10.2% and 4.8%, respectively, and the rate by S. rubrovittatus and P. exiguus at dough ripe stage was 4.3% and 2.7%, respectively. The damage shape of pecky rice was distinctive according to the species. The surface of pecky rice by P. exiguus was very smooth but the surface of pecky rice by E. aeneus was rough and caved. In the pecky rice by S. rubrovittatus, the spot occurred at the topside of the grain.

• Korean journal of applied entomology
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• v.52 no.4
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• pp.437-448
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• 2013

Hemipteran bugs, which were previously considered as secondary pests, have currently become important pests of numerous crops. Among them, Riptortus pedestris (Fabricius) is a major species that occurs in Korea, Japan, China, and South Asian countries. Riptortus pedestris infests leguminous crops like soybean, vetches, and red clover; fruit trees like persimmon and yuju; and grains like barley, foxtail millet, broomcorn, and sorghum. Riptortus pedestris causes the greatest damage to soybean, as it is the most suitable host for the bug. Feeding damage during pod formation significantly reduces the yield of soybean. Currently, 17 insecticides, including diazinon and etofenprox, are registered for the control of hemipteran bugs in Korea, and growers apply insecticides two to three times on a regular basis. Aggregation pheromone traps are widely used as a monitoring tool and partial control measure. The aggregation pheromone of R. pedestris attracts conspecific adults and nymphs and is used for food exploitation rather than sexual attraction. In addition, the pheromone serves as a kairomone for egg parasitoids such as Gryon japonicum (Ashmead) and Ooencyrtus nezarae Ishii. As a new method of pest management, nonviable host eggs were included in the pheromone trap to catch R. pedestris and propagate parasitoids. As a part of cultural practices, resistant soybean varieties with specific color and size of pod and control of flowering time through the alteration of planting date can be used. For the effective management of R. pedestris in the near future, development of cultural practices that can support natural control factors and the use of multiple control tactics are needed.