• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.4
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• pp.398-410
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• 1982

Summer crops grown in uplands are greatly diversified and show a large variation in difference with year and location in Korea. The principal factor for the variation is weather, in which precipitation and temperature play a leading role and such a weather factors as wind, sun lights also influence production of the summer crops. Since artificial control of weather conditions as a main stress factor for crop production is almost impossible, it must be minimized only by an improvement of cultivation techniques and crop improvement. Precipitation plays a role as one of the most important factor for production of the summer crops and it is considered in two aspects, drought and excess moisture. This country, which belongs to monsoon territory, necessarily encounter one of this stress almost every year, even though the level is different. Therefore, the facilities for both drought and excess moisture are required, but actually it is not easy to complete for them. On this account, crops tolerant to drought, excess moisture and pests should be considered for establishing summer crops. For the districts damaged habitually every season, adequate crops should be cultured and appropriate method of planting, drainage and weed control should be applied diversely. Injuries by temperature is mainly attributed to lower temperature particularly in late fall and early spring, although higher temperature often causes some damages depending upon the kind of crops. Sometimes, lower temperature in summer season playa critical role for yield reduction in the summer crops. However, certain crops are prevented to some extent from this kind of stress by improving varieties tolerant to cold, hot weather or early maturing varieties. As is often the case, control of planting time or harvesting is able to be a good management for escaping the stress. Lodging, plant diseases and pests are considered as a direct or indirect damage due to weather stress, but these are characters able to be overcome by means of crop improvement and also controlled by other suitable methods. In addition, polytical supports capable of improving constitution of agriculture into modern industry is urgently required by programming of data for the damages, establishment of damage forecasting and compensation system.

• Weed & Turfgrass Science
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• v.2 no.1
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• pp.62-69
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• 2013

The black cutworm, Agrotis ipsilon (Hufnagel), damages various cultivated crops and it can also be a serious pest of turfgrass, especially on golf courses. Essential oils have potential as alternative control agents for insect pests. Sixteen essential oils (anise, camphor, cinnamon, citronella, clove, fennel, geranium, lavender, lemongrass, linseed, neem, peppermint, pine, thyme, turpentine and tea saponin) and paraffin oil were assessed in the laboratory, the green house and field trials for their efficacy against black cutworms in turf. Treatment of potted cores of perennial ryegrass turf with anise, cinnamon, neem, paraffin or turpentine reduced black cutworm damage in a greenhouse trial, and in a similar trial, applying neem oil at 4000, 2000 and 1000 ppm resulted in 100, 100 and 64% mortality, respectively, of black cutworms. Weight of survivors at the 1000 ppm rate was 5- fold less than weight of comparably-aged controls. Neem oil (2000 ppm) reduced growth of black cutworms feeding on treated clippings. A high rate of neem oil followed by irrigation (0.1 L of 20000 ppm neem oil with 0.9 L watering/$m^2$) was more effective than a lower concentration (1 L of 2000 ppm neem oil/$m^2$) against $2^{nd}$ and $3^{rd}$ instars in potted turf cores and field plots, respectively. However, not even the aforementioned higher rate effectively controlled $4^{th}$ instars in the field.

• Korean Journal of Organic Agriculture
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• v.21 no.4
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• pp.685-699
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• 2013

This study was evaluated the effect of attractant or repellent plants for establishing push-pull strategy for insect pest management of organic Chinese cabbage cultivation. The attractant or repellent effect of Ten plants, marigold, rye, Chinese chive, lettuce, chicory, Nongwoo-chicory, crown daisy, Treviso, green leaf mustard, and red leaf mustard were evaluated against diamondback moth, striped flea beetle, aphids, brown-winged stink bug and cabbage stink bug in organic Chinese cabbage field in Seosan in 2012. Of the ten repellent or attractant plants, rye and chicory attracted significantly brown-winged stink bug and cabbage stink bug, respectively. Aphids ate attracted significantly to the rye rather than the other plants. Leaf mustard was attracted cabbage stink bug and brown-winged stink bug in order. Cabbage stink bug was attracted by only a combination of lettuce and Chinese chive. Diamondback moth, striped flea beetle, aphid, brown-winged stink bug and cabbage stink bug were significantly repelled by single or combined cultivation of crown daisies, Treviso, and leaf mustard in organic Chinese cabbage cultivation. The results above-mentioned indicate that selected insect-attractant and -repellent plants can be used as tools for integrated pest managements of Chinese cabbage.

• Korean journal of applied entomology
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• v.36 no.1
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• pp.30-36
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• 1997

Except for a cosmopolitan and major pest of apples, Tetranychus urticae Koch, Tetranychus mites in Korea such as T. viennensis Zaher, T. kanzawai Kishida, and T. truncams Ehara have been considered as quarantine pests by Canada and United States. Even though these mites are not feeders on apples, they are suspected to attach accidentally on apple h i t s in autumn as females enter the diapause. The characters used to identify Tetranychus mites have been confined to the shape of aedeagus in adult male. To develope a fast and accurate alternative identification protocol applied to hibernating female mites on apples, their mitochondrial DNA (mtDNA) were examined to find out any polymorphisms to discriminate each species from the other ones. Three pairs of primers for polymerase chain reaction (PCR) were used to amplify cytochrome oxidase subunit I (CO-I) coding region in mitochondrial DNA5 of four species of Tetranycus mites. The longest amplified product was estimated its size as about 680 bp. Digestion with restriction enzymes, AluI, Ddel, and Sau3A, showed length polymorphisms, which will he useful as diagnostic markers to identify Tetranychus mites. Schematic restriction maps in amplified region were shown for each species.

• Journal of Life Science
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• v.28 no.3
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• pp.369-375
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• 2018

Mycoplasma genitalium has 367 conserved genes and the smallest genome among mono-culturable prokaryotes. Conservative metabolic pathways were examined among M. genitalium and 14 prokaryotes, one hyperthermophilic exosymbiotic archaeon Nanoarchaeum equitans and 13 intracellular eubacteria of plants or insects, with fewer conserved genes than M. genitalium. They have 11 to 71 metabolic pathways, however complete metabolic pathways ranged from 1 to 24. Totally, metabolic pathway hole is very high due to the lack of 45.8% of the enzymes required for the whole metabolic pathways and it could be suggested that the shared metabolic pathway with the host's enzyme would work or the essential substances are host dependent. The number of genes necessary for mass transfer through the cell membrane is also very low, and it may be considered that the simple diffusion or the protein of the host will function in the cell membrane of these prokaryotes. Although the tRNA charging pathway was distributed in all 15 prokaryotes, each has 5-20 tRNA charging genes. This study would give clues to the understanding of the metabolic pathways of intracellular parasitic bacteria of plant and endosymbiotic bacteria of insects, and could provide basic data for prevention of crop damage, development of insect pests and human medicines.

• The Korean Journal of Pesticide Science
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• v.8 no.1
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• pp.38-45
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• 2004

To elucidate the photolysis characteristics of the insecticide imidacloprid in the environment, $[^{14}C]$imidacloprid was treated into water and paddy soil-water system. In water system, the amount of $^{14}C$-radioactivity distributed in aqueous phase was rapidly increased up to 80% of total $^{14}C$ in water during 7 days of exposure to sunlight. Also, the amounts of imidacloprid in water at day 0 and 3 days after treatment were 1.2461 and 0.8594 mg/kg, respectively, not being detected 7 days after treatment, indicating rapid degradation of imidacloprid in water by sunlight. One photodegradation product, imidacloprid urea, in which the $N-NO_2$ moiety of imidacloprid was replaced by oxygen, was detected from water in water and water-paddy systems. The amount of the metabolite detected from water in water system was 0.0112 mg/kg 1 day after treatment and reached the top concentration of 0.0391 mg/kg 7 days after treatment. In case of water-paddy system, its amount was 0.0117 mg/kg 1 day after treatment and reached the highest concentration of 0.0259 mg/kg 3 days after treatment. Rapid transformation of imidacloprid into polar compounds continued until 7 days after treatment, considering that 80% of $^{14}C$ in water distributed in aqueous phase 7 days after treatment, amount of imidacloprid was 1.6538 mg/kg at day 0 and 0.8785 mg/kg 1 day after treatment, not being detected after 15 days, indicating rapid degradation of imidacloprid in water-paddy soil system by sunlight. The direct degradation of imidacloprid to imidacloprid urea would be a major photodegradation pathway in water and water-paddy soil systems.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.11
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• pp.1684-1690
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• 2010

The properties of non-waxy rice, Dongjin 1, cultivated with conventional farming (CF) and environmentally-harmonized farming (EHF) using hairy vetch were compared to determine rice water absorption, physicochemical and pasting properties, antioxidant activities of brown and white rice, and a sensory evaluation of cooked white rice was carried out. EHF was treated with green manure crops such as hairy vetch and chitinase, which produce microorganism culture solution. CF was applied with seed disinfection treatments, fertilizer herbicides, and agricultural chemicals for the control of pests and diseases. The absorption level of EHF rice was higher than that of CF rice grain, regardless of the cultivation methods used. The ash and crude lipid contents were higher, but protein and dietary fiber contents were lower in the CF rice than in the EHF rice. The total starch content, water binding capacity, and swelling power of white rice were higher than those of brown rice, regardless of the cultivation methods used. The DPPH's antioxidant activity was shown as follows: EHF brown rice, EHF white rice and CF rice, in a decreasing order. The initial pasting temperature of EHF rice was lower than that of CF rice, but the peak, cold, and breakdown viscosities exhibited reverse trends. The sensory evaluation showed that the cooked white rice cultivated with EHF was not significantly different from that cultivated with CF (p<0.05). The overall preference of cooked rice did not show significant differences between the two cultivation methods (p<0.05).

• The Korean Journal of Pesticide Science
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• v.10 no.2
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• pp.131-137
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• 2006

This experiment was conducted to select prominent microorganisms with a good insecticidal activity among the ten species, which isolated from soil at the near of Chung-buk, Chung-nam, and Gang-won provinces and made protein crystal endotoxin. As a result, GB-413 strain was finally selected, which showed the high insecticidal activity against susceptible diamondback moth (Plutella xylostella), beet army worm (Spodoptera exigua) and tobacco cutworm (Spodoptera litura) as well as resistant diamondback moth strains. By modifying the cultivation process f.g. lowing the glucose concentration at early cultivation stage and adding the carbon after inducing the spores, the percentage of making spore as well as the number of active spore were increased and the time for cultivation and spore forming was reduced without a reduction of insecticidal activity. These results were not only applied successfully for the optimized cultivation process for a fermentation tank containing five tons capacity, but also improved the possibility of mass cultivation for commercial production.

• Korean journal of applied entomology
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• v.49 no.2
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• pp.129-137
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• 2010

Four major agricultural insect pests, Bemisia tabaci, Myzus persicae, Plutella xylostella and Tetranychus urticae, were irradiated with 30, 50, 70, or 100 Gy electron-beam. Longevity, egg hatching, emergence, and fecundity of the test insects were measured. Hatchability of B. tabaci, P. xylostella and T. urticae declined with increasing irradiation doses, and all B. tabaci and T. urticae eggs were dead at 100 Gy. When eggs of B. tabaci, P. xylostella and T. urticae were irradiated, hatch was inhibited. B. tabaci adults grown from 70 Gy irradiated eggs did not lay eggs. Fecundity of P. xylostella from the 100 Gy irradiated eggs decreased. When B. tabaci, P. xylostella, M. persicae and T. urticae nymphs/larvae were irradiated, the results were similar as those of the hatched eggs. When P. xylostella pupae were irradiated with 100 Gy, fecundity of emerged adults decreased and no eggs hatched. When B. tabaci, P. xylostella, M. persicae and T. urticae adults were irradiated with 70 and 100 Gy, fecundity decreased and egg hatch of B. tabaci was inhibited. However, the longevity of adults did not change and electron-beam irradiation of all developmental stages had no effect on the longevity of adults.

• Korean journal of applied entomology
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• v.57 no.3
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• pp.143-149
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• 2018

The black pine bast scale (BPBS), Matsucoccus thunbergianae (Homoptera: Margarodidae), is one of the most serious insect pests of Japanese black pine (Pinus thunbergiana) in Korea. The density of BPBS varies by tree, branch, and location, making it difficult to monitor them. This study investigated to find a monitoring method for distribution and occurrence of BPBS on Japanese black pine using the yellow sticky trap. The density of male BPBS on sticky trap and nymphs from the branch of Japanese black pine was highly correlated in various surveyed sites. The number of male BPBS that attracted to the yellow sticky traps was higher in upper crown than the lower crown of P. thunbergiana but this was not statistically significant. The density of BPBS nymphs increases with the increase of the diameter of the branch, but the differences were not significant from 1 to 2.5 cm. BPBS was highly distributed in bottom-faced branch than the upper-faced branch of P. thunbergiana. Therefore, we suggest, the yellow sticky trap for the monitoring of BPBS and when examining the nymph density in branch, it is recommended that the bottom-faced branch of the 2-2.5 cm diameter branch be examined.