• Journal of Sericultural and Entomological Science
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• v.51 no.1
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• pp.1-8
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• 2013

This study was conducted for investigation of habitat and development of indoor-rearing conditions of peacock butterfly, Inachis io (Linnaeus). Three different region, Mt. Kwangduk-san, Mt. Hae-san and Mt. Taebaek-san in Kangwon-do, was selected for investigation of domestic distribution and ecological environment of peacock butterfly. In result, there are many butterflies in the only two region, Mt. Kwangduk-san and Mt. Hae-san. On 16th April, 4 overwintered butterflies were observed in Mt. Hae-san. At the end of June and early in July, 51 individual next generation's butterflies were observed in Mt. Kwangduk-san and Mt. Hae-san. For development of indoor-rearing conditions, collected each 15 male and female peacock butterflies was reared in a room condition. Female butterflies laid eggs in the egg cluster on the underside of host-plant's leaves, Urtica angustifolia Fisch., in the ovipositioning room. We took 11 egg cluster with average $404.6{\pm}23.6$ eggs. Hatchablity of eggs was 92.3%, and the eggs hatched within $5.1{\pm}0.9$ days from the day of oviposition under high temperature, long day condition($25^{\circ}C$, 14L:10D). The larval period was $18.3{\pm}1.0$ days under high temperature, long day condition($25^{\circ}C$, 14L:10D), showing 81.0% pupal ratio. The head width of each developmental larval stage were $0.37{\pm}0.01mm$(1st instar), $0.66{\pm}0.02mm$(2nd instar), $1.07{\pm}0.05mm$(3rd instar), $1.81{\pm}0.07$(4th instar), $2.76{\pm}0.08$(5th instar). The pupal period was $8.4{\pm}0.6$ days, and the emergence rate was 87.5%.

• Korean journal of applied entomology
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• v.50 no.2
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• pp.157-165
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• 2011

Enterobacteria were isolated in the gut of the predacious multicolored Asian ladybird beetle, Harmonia axyridis, and their effects to the development of H. axyridis were examined. Populations of H. axyridis in this experiment were collected from Kimjae at Cheonbuk province (JK population), Geumsan at Chungnam province (CK population) and laboratory population at Laboratory of Insect Physiology in Chungnam National University, Daejeon. Thirty-four enterobacteria isolates were purified and isolated from the digestive tract of H. axyridis, and a total of 4 strains were classified into group by analysis of 16S rRNA gene sequences. About 70% of total isolates were phylogenetic groups of Bacillus genus and Staphylococcus genus, and they were commonly separated from the digestive tract of H. axyridis. After investigating their susceptibility against antibiotics with 18 representative enterobacteria isolates, ofloxacin and penicillin were selected for examination in this study of their ability to inhibit the growth of all of isolates. In order to remove the enterobacteria from the aphids, ofloxacin and penicillin were given to the green peach aphid, Myzus persicae, and the turnip aphid, Lipaphis erysimi. These aphids were provided to H. axyridis as prey. The weight of pupa, developmental periods of each larval instar, the number of eggs and their hatching ratio of H. axyridis with treatment aphids were lower compared with non-treatment aphids. Staphylococcus saprophyticus is a representative enterobacteria and commonly isolated from the digestive tract of H. axyridis. In the absence of S. saprophyticus, the developmental periods of each larval instar increased; however, the weights of pupa, the number of eggs, and their hatching ratio decreased.

• Korean journal of applied entomology
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• v.57 no.2
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• pp.57-64
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• 2018

The fungus gnat, Bradysia difformis, has been recognized as an important pest of greenhouse crops. There is a need for research on the control of the fungus gnat. However, it is difficult to obtain many generations of the fungus gnat for several kinds of research. Indoor propagation is a very useful method for obtaining enough individuals in cases where the need is for larvae in soil. This study was conducted to determine the optimum growing media and temperature conditions for rearing the fungus gnat in the laboratory. Under experimental temperature conditions, hatching, pupation, and eclosion rates were the highest at $20^{\circ}C$. The developmental period of the fungus gnat was shortened with higher temperatures. The greatest number of eggs was an average of 144 at $20^{\circ}C$. Using different types of larvae growth media, the highest hatching rates were 84.7 and 84.4% in water agar and potato disks, respectively. The larval period was the shortest, at 14.7 days, when grown on potato disks. The highest pupation and eclosion rates were 85.2 and 82.6% on potato disks, respectively. The highest number of eggs was an average of 125.6 on potato disks. Regarding the effects of different growth media on the eclosion rate of B. difformis, the highest eclosion rate was 88.4% on the soil mix, and was 50% on oatmeal, 25% on shredded potato. The results of four different inoculation levels of larvae on eclosion rate of B. difformis showed that the highest eclosion rate was 84.7% for 1,000 larvae. The eclosion rate was shortened with a higher number of larvae inoculated/cage. In the growth medium used, 3,000 eggs were better for the initial level of inoculation, showing a relatively high emergence rate and short developmental period. Mass rearing procedures were explained in detail.

• Korean journal of applied entomology
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• v.53 no.4
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• pp.427-433
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• 2014

To investigate the biological control of Aulacorthum solani, a comparative analysis was carried out using an indigenous natural enemy, Ephedrus plagiator, and an exotic parasitoid, Aphidius ervi. Lifespan, spawning periods, number of mummies, number of offspring, and developmental periods of the two parasitoids on Aulacorthum solani and Acyrthosiphon pisum were studied at 15, 20, 25, and $30^{\circ}C$ with a photoperiod 16 h (L): 8 h (D). The lifespan of E. plagiator (5.3 days) was relatively higher than that of A. ervi (2.3 days) when these parasitoids were reared on A. solani at $15^{\circ}C$. Similarly, the spawning period of E. plagiator (5.3 days) was longer than that of A. ervi (2.2 days). When the two aphid parasitoids were provisioned with A. solani, the numbers of E. plagiator mummies at 15, 20, 25, and $30^{\circ}C$ were 71.5, 41, 15.7, and 7.7, respectively, whereas at the same temperatures, the numbers of A. ervi mummies were 22.1 16.3, 6.2, and 0.4, respectively. In contrast, when provision with A. pisum, the numbers of E. plagiator mummies at 15, 20, 25, and $30^{\circ}C$ were 70.3, 69.8, 34.3, and 8.4, whereas the numbers of A. ervi mummies were 93.4, 71.2, 34.8, and 14.5, respectively. The numbers of E. plagiator offspring emerging at 15, 20, 25, and $30^{\circ}C$ were 42.1, 36, 11.6, and 0, whereas the numbers of A. ervi offspring emerging were relatively lower at 19.6, 13.5, 3.7, and 0.1, respectively. By comparing these results, it can be concluded that E. plagiator is a more efficient parasitoid of A. solani, whereas A. ervi is more efficient on A. pisum.

• Journal of Aquaculture
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• v.15 no.2
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• pp.95-101
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• 2002

During the periods from lily to October, 2000 in Hongseong and lucy to October, 2001 in Taean in the west coast of Korea, the following environmental conditions prevailed : water temperature : 22.0~26.817, salinity 27.23 ~30.80%, dissolved oxygen 4.12 ~6.26 ml/l, pH 7.89 ~8.09, phosphate 0.39 ~0.65 $\mu m$ , inorganic nitrogen 5.05~9.26 $\mu m$, suspended solid 5.4~20.8 mg/l and chemical oxygen demand 1.12~1.87 mg/l. The B-shaped veliger larvae of the Ark shell occurred in maximum number at $25^{\circ}C$ prevailing from mid-August at Hongseong and Taean. Full grown larvae reached maximum abundance from late August. To identify the effectiveness of the substratum for spat collection, raschel net were tested to Larval settlement. The most effective depth to collect the larvae in natural environment was the collectors suspended at 7~8 m depth. At these depths, about 49 to 94 spats were found on the collector (40$\times$50 cm), The growth of shell height (Y) to shell length (X), and total weight (W) to shell length (L) could be formulated as follows respectively: Hongseong: SH = 0.7168 SL -0.6466 ( $r^2$ = 0.9839), TW = $0.0001SL^{3.1705}$ ($r^2$ = 0.9882) Taean: SH = 0.736 SL -0.8824 ($r^2$ : 0.9899), TW : 0.00005 $SL^{3.3731}$ ($r^2$ : 0.9899)

• Journal of Korean Society of Forest Science
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• v.83 no.3
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• pp.311-321
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• 1994

Experiments were conducted to evaluate the efficacy of ground and foliar sprinkling of natural water for control of the pine needle gall midge, Thecodiplosis japonensis, by disturbing the reproductive behavior of adults such as copulation and oviposition. Diurnal ground spray for whole area application and foliar spray for single tree treatment were tested at day time during the period of adult emergence. The results obtained are as follows : 1. The population density of overwintering larvae in soil was not affected by the water spray during the adult emergence period. 2. Spraying the water showed no effect on the whole period and number of adult emergence, but retarded early emergence and facilitated Late emergence. The difference in the emerging time by 50% emergence day was approximately 7 days. 3. Ground spray was significantly different from control in gall formation rates but was not sufficient for effective control. As a single-tree treatment, the foliar spray was found to be highly effective for control of the pine needle gall midge, Average gall formation of spray plots and untreated ones were 2.6% and 38%, respectively ; control value exceeded 90%. 4. Ground spray of water was not effective in reducing larvae in gall of needle. Foliar spray, however, reduced 45% of larval numbers. 5. Foliar spray accelerated shoot growth by 15%-18%. 6. Foliar spray was highly effective for the control of sucking insects, such as mites and aphids on pine trees.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.1
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• pp.30-39
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• 1989

Forage productivity of cropping systems of rye - silage corn, silage corn - oats, silage corn - rape was studied in the south-eastern part of Korea where rice black-streaked dwarf virus(RBSDV) infection of corn are severe. Rye(cv. Paldanghomil) was planted on Oct. 20 of 1986 and harvested 10 times from April 5 to May 5 at the 5-day intervals in 1987, corn (cv. Suweon 19 and Jinjuok) was planted 5 times from April 5 to May 15 at the 10-day intervals in 1987, and oats(cv. Megwiri) and rape (cv. Velox) were planted 4 times from Sept: 4 to 25 at the 7-day intervals and harvested 4 times from Nov. 10 to Dec. 10 at the 10-day intervals in 1987. Considering yield, nutrition value, and in vitro dry matter digestibility (IVDMD), forage productivity of the cropping systems was compared. As harvesting time of rye delayed, plant height, dry matter(DM) yield, percent DM, crude fiber, and digestible DM yield increased, but crude protein, crude fat, and IVDMD decreased. However, nitrogen free extract was not different among the harvesting dates. As planting date of corn delayed, RBSDV infection rate increased. but DM yield of silage decreased. However, silage yield of Jinjuok was higher, but RBSDV infection rate was lower compared with Suweon 19 at all planting dates. DM yield of oats and rape decreased as planting date delayed. However, at Sept. 4 and 11 plantings yield of oats on Nov. 10 was much lower than that of rape, but the differences in yield between two crops decreased with delayed harvesting, and yield was similar on Dec. 10. A cropping system harvesting rye around April 20 and followed by planting corn in late April was best among the rye-corn systems considering yield and nutrition value of both crops. However, among the corn-oats or corn-rape cropping systems early April planting of corn and followed by early Sept. planting of oats or rape showed best results with similar yield potential of the best rye-corn cropping system.

• Korean journal of applied entomology
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• v.40 no.3
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• pp.203-209
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• 2001

Development and reproduction of the sweetpotato whitefly, Bemisia tabaci(B biotype) were investigated under different temperatures and host plants. Developmental periods from egg to pre-adult of whiteflies measured under four constant temperatures: they were 86.2 days at $15^{\circ}C$ and 17.0 days at $30^{\circ}C$. Lower threshold temperature and total effective temperature for the development of egg and nymph, and for the complete development (egg to emergence) were $10.1,\;11.6,\;11.1^{\circ}C$ and 110.3, 204.7, 317.3 degree days, respectively. The hatching and emergence rates were 87.0% at $25^{\circ}C$ and 76.7% at $20^{\circ}C$, which were higher than the results of other temperatures. The adult longevity was 23.6 and 14.0 days at $20^{\circ}C$ and $30^{\circ}C$, respectively. The highest average fecundity per female was 103.3 at $25^{\circ}C$. But there were no significant differences among the temperatures. The highest intrinsic rate of natural increase($r_{m}$) was 0.196 at $30^{\circ}C$ and the highest net reproduction rate ($R_{o}$) was 97.33 at $25^{\circ}C$. Developmental periods from egg to pre-adult of whiteflies were 21.2 on the tomato, 28.1 on red pepper, 22.2 on eggplant and 25.5 days on poinsetia. The hatching was highest (90.3%) on red paper and emergence rate was highest (89.6%) on eggplant. The longest longevity of adult female was 26.5 days on eggplant, and the average fecundity per female was greater on tomato and eggplant than on other host plants. The intrinsic rate of natural increase($r_{m}$) was the highest on tomato as 0.165 and the net reproduction rate ($R_{o}$) was the highest on eggplant as 106.1. As a result, the optimum range of temperature for the growth of B. tabaci was between $25^{\circ}C$ and $30^{\circ}C$, and the optimum host plant were tomato and eggplant among the plants tested.

• Korean journal of applied entomology
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• v.24 no.4 s.65
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• pp.209-218
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• 1986

This study was performed to evaluate the differences in resistance of rice varieties to biotypes of the brown planthopper (BPH), capable of surving on the Milyang 30 and Milyang 63 varieties which have Bph 1 and bph 2 gene for resistance, respectively. The rice varieties tested were Milyang 30, Cheongcheong, Milyang 63 and Gaya which have been reported as having resistant genes for the BPH. The check varieties were Chucheong and Sangpoong which have no resistant gene. The degree of resistance to the BPH biotypes indicated that Milyang 30, Cheongcheong, Milyang 63 and Gaya varieties were highly resistant to the biotype 1. But their reactions against biotype 2 and 3 were variable, namely Milyang 30 and Cheongcheong were susceptible to biotype 2, and Milyang 63 was susceptible to biotype 3. In the esterase isozyme patterns of brown rice the bands of ${\beta}-1,\;{\beta}-3\;and\;{\beta}-5$ were detected in Chucheong and Sangpoong, while the bands of ${\alpha}-1,\;{\beta}-2\;and\;{\beta}-5$ were detected in the test varieties which have genes for resistance. However, the bands of ${\beta}-5$ in Milyang 63 and Gaya were stronger than those of Milyang 30 and Cheongcheong varieties. In the root of 10-days seedling, the esterase bands of ${\alpha}-2,\;{\beta}-2\;{\beta}-4\;and\;{\beta}-5$ were detected in Chucheong and Sangpoong, while the bands of ${\alpha}-1,\;{\beta}-1\;{\beta}-3\;and\;{\beta}-5$ were detected in the tested different varieties. But the bands of ${\alpha}-1\;and\;{\beta}-5$ in Milyang 63 and Gaya were stronger than those of Milyang 30 and Cheongcheong varieties.

• Korean Journal of Poultry Science
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• v.38 no.3
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• pp.165-171
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• 2011

This study was conducted to investigate the effects of dietary supplementation of copper-soy proteinate (Cu-SP) on the performance of laying hens. A total of 1,000 Hy-Line Brown laying hens of 32 wks old were assigned to one of the following 5 dietary treatments: Control, Cu-SP 50, 100, 150, 200 (50, 100, 150, 200 ppm Cu supplementation as Cu-soy proteinate). Each treatment was replicated 4 times with fifty birds per replication, housed in 2 birds cages. Fifty birds units were arranged according to randomized block design. Feeding trial lasted 5 wks under 16L : 8D lighting regimen. There were no significant differences among treatments in hen-day and hen-house egg production, egg weight, broken & soft egg production. Feed intake and feed conversion rate (FCR) were significantly (P<0.01) lower in Cu-SP treated groups than Control. Eggshell thickness was significantly (P<0.01) higher in Control than Cu-SP 100, 150 and 200. Egg yolk color index was significantly (P<0.01) higher in Cu-SP 200 than other treatments. Egg shell color index was significantly (P<0.05) higher in Cu-SP 150 and Cu-SP 200 than Cu-SP 100. Concentration of copper, iron and zinc of the egg yolk were not significantly influenced by treatment. There were no significant differences in the level of leukocytes and erythrocytes in the chicken blood. The result of this experiment showed that dietary supplementation of Cu-SP at the level of 50ppm of Cu can reduce feed intake and FCR.