• Journal of Sericultural and Entomological Science
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• v.54 no.1_2
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• pp.17-22
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• 2016

Rearing environment direct effects on oviposition preference of black soldier fly(Hermetia illucens). In this study, the number of egg-filled flutes was surveyed according to the size of adult rearing cages and oviposition media of black soldier fly (BSF). The height of the adult rearing cages were fixed at 2 m and provided different sizes of width and length and released 20,000 BSF adults in the rearing cages. The mean number of BSF egg-filled flutes was 895.4 at $4{\times}4m$ cage, 876.3 at $2{\times}1m$ cage and 62.3 at $1{\times}1m$ cage. Comparison of egg-filled flutes was according to cages material of adult BSF. The mean number of egg-filled flutes were 820.7 and 604.3 at different cage materials such as mosquito net and green house film. The mean numbers of egg-filled flutes were 326.6 in green floral form, 135.2 in green corrugated cardboard and 41.0 in brown corrugated cardboard. And the mean number of egg-filled flutes were similar floral form with the corrugated cardboard was overlapped by floral form such as 57.7 and 64.7. The mean number of egg-filled flutes was 29.0 and 48.2 in 6 mm and 4 mm diameter of oviposition hole.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.18 no.2
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• pp.104-109
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• 2013

The spawning characteristics of Hexagrammos agrammus and Hexagrammos otakii was directly observed in coastal regions of the Yellow Sea and South Sea during the spawning seasons using scuba diving. The territorial male H. agrammus showed different body size, nuptial coloration and nest location compared to those of H. otakii, even though both species caring egg masses were found at the almost same depths. In the West sea, a relatively small guardian H. agrammus male protects 1-2 egg masses laid on a clump of red algae within his territory. The territorial males in red nuptial coloration and their egg masses were well camouflaged in their surroundings. Contrary to H. agammus, a guardian H. otakii male in yellowish nuptial coloration protects 4-8 egg masses in a nest. In addition, their nests were located on the relatively open environments such as discarded fishing nets, rock crevices and a clump of algae. The results of present study shows that even though both of two species belonged to Hexagrammidae, they have different strategies for spawning and protecting their egg masses.

• The Korean Journal of Ecology
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• v.23 no.1
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• pp.65-70
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• 2000

Field collections were made from six gypsy moth (Lymantria dispar L.) Populations in Kyonggy and Cheju areas during the period 1987∼1997. Characteristics of gypsy moth populations at different phases were examined in terms of egg mass density, relative larval density, plant damage, and fecundity. Males captured in pheromone trap were recorded, and we examined if there was a relationship between numbers captured and the population density during the following generation. Egg mass density was closely related with larval density, and furthermore these densities were correlated with the level of plant damage, indicating that larval dispersion was limited in oviposition areas. The gypsy moth population cycle was short in Korea with the period from population development to innocuous level usually lasting 2∼3 years. Male caught by pheromone trap (mean number of males caught per trap per day in peak emergence period) was positively correlated with egg mass densities in the following season (r²=0.93). A low fecundity was detected from outbreak populations which accompanied defoliation. Fecundity of gypsy moth ranged from 538 to 601 at other phases.

• Korean journal of applied entomology
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• v.50 no.4
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• pp.367-372
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• 2011

An unknown planthopper was discovered in 2010 in an apple orchard in Sinpoong-myun, Gongju-si and in a blueberry orchard in Deogsan-myun, Yesan-gun. This pest have arrived 4 or 5 years ago and the population density then rapidly increased. It was identified as Ricania sp. by Dr. Murray J. Fletcher. Adult Ricania sp. was found on 26 plants including blueberry, grape, peach, sumac, japanese angelica, jujube, kiwi, Rubus coreanus, apple, apricot, plum and chestnut. Females lay eggs on 1-year-old branches. The mean number of eggs laid on apple and plum were 18.7 and 15.3, respectively. The mean length of egg masses on apple and plum were 12.35 and 11.45 mm, respectively. The distance between eggs laid on apple and plum branchs were 1.3 and 1.5 mm, respectively. The mean number of eggs in the same length of egg mass on apple and plum branchs were 17.1 and 13.3, respectively.

• Proceedings of the Korean Society of Crop Science Conference
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• 2023.04a
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• pp.89-89
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• 2023

• The Korean Journal of Ecology
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• v.22 no.5
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• pp.299-303
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• 1999

Studies were conducted in Mt. Namsan, Seoul, during the summer of 1997 and 1998 using racemic disparlure to determine seasonal occurrence and circadian activity in male gypsy moth, and size of egg mass and wing length of male moth. Male gypsy moths occurred from middle part of July until middle part of August and peaked in late part of July. Circadian activity of male moths initiated from 12: 00h and continued until 21: 00h, and the peak time was between 14: 00h and 17: 00h. Mean number of moths captured per trap in 1997 was larger than that in 1998, however, eggs per mass, egg size and wing length were not significantly different between the two years, 1997 and 1998.

• The Korean Journal of Pesticide Science
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• v.20 no.4
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• pp.281-285
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• 2016

This study was conducted to investigate the characteristics of oviposition and the effect of density suppression by yellow-colored sticky trap on Ricania shantungensis in blueberry. The occurrence of an egg mass of R. shantungensis in the upper, middle and lower region were 56.6~60.2%, 23.8~28.1% and 11.7~19.7%, respectively. The number of egg masses in the branch was investigated. Percentage of the branch with one egg mass was greatest (50.9%) than with two (20.5%), three (14.6%) and over four (14.0%). The effect of yellow-colored sticky trap to reduce the number of R. shantungensis egg masses in blueberry was also investigated. In a month after yellow sticky trap installation, 17.1 adults of R. shantungensis were attracted per trap. Moreover, the number of egg masses on a tree in yellow-colored sticky trap plot was much lower (0.4) than control (1.3). Consequently, this result shows that use of yellow-colored sticky trap may contribute to decrease ovipisotion rate of R. shantungensis in blueberry.

• Korean journal of applied entomology
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• v.53 no.3
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• pp.311-315
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• 2014

Lantern fly(Lycorma delicatula) is a major invasive pest that causes withering symptom of agricultural crops by sucking tree sap and sooty mold symptom by producing honeydew. This study was conducted to investigate the occurrence pattern of lantern fly in grape orchards in Gyeonggi area and the effect of winter temperature on L. delicatula egg survival during 2010 to 2013. In Gyeonggi areas, overwintered L. delicatula eggs began to hatch from early May and nymphs peaked in mid May. Adults emerged from late July and laid eggs until early November. The survival of L. delicatula eggs during overwintering was largely affected by winter temperatures. The relationship between the number of days below a threshold temperature (x) in January and the survival rate of overwintering L. delicatula eggs (y) was using linear regression model. The best model selected by the lowest RSS (residual sum of square) between predicted and actual survival was y = -1.0486 x + 94.496 ($R^2=0.7067$) with $-11^{\circ}C$ of threshold temperature. These results should be helpful to conduct L. delicatula management programs, since the results provided relivable prediction for the winter survival of L. delicatula eggs and the phenology of egg hatch in the spring.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.343-344
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• 2003

그물베도라치 Dictyosoma burgeri는 농어목 황줄베도라치과 그물베도라치속에 속하는 어류로서 우리 나라와 일본 연안의 암초지대와 조간대 상부 조수 웅덩이에 분포하는 정착성 어종이다. 몸에는 옆줄과 수직방향으로 직선이 그어져 있고 세로줄의 점액공이 있어 옆구리는 그물 모양을 나타낸다(정, 1977). 그물베도라치는 암컷이 약 2.1 mm의 덩어리진 침성점착란을 산란하고, 수정 후에는 수컷이 몸으로 난괴를 감싸 부화할 때까지 보호한다(단원 과 도진, 1972). (중략)

• The Korean Journal of Malacology
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• v.23 no.2
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• pp.189-198
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• 2007

The reproductive cycle, egg capsules in the egg-mass, first sexual maturity, and sex ratio of the bladder moon, Glossaulax didyma ($R\ddot{o}ding$) were investigated. The gastropods collected from the intertidal zone of Biin Bay, Seocheon, Korea were studied by using histological analysis and morphometric data. The gonadosomatic index (GSI) of females and males began to increase in March and reached maximum in May. Then their values sharply decreased from late in May to August due to spawning. The condition index (CI) began to increase in February and reached maximum in May, then gradually declined in the spawning period. The CI calculated for determination of the spawning period was coincided with changes in the GSI and gonadal phases. Spawning occurred between late in May to August in females and early in May to August in males. Spawning peak was observed between July and August when the seawater temperature rose to 19 $^{\circ}C$. Reproductive cycle with the gonadal development phases of this species can be divided into five successive stages in females and four in males: in females, early active stage (December to February), late active stage (February to March), ripe stage (April recovery stage (August to November); in males, active stage (December to March), ripe stage (March to July), copulation stage (early May to August), and recovery stage (August to January). Fully matured oocytes were approximately 250-270 ${\mu}m$ in size. The egg-mass was a hat in shape, and a number of egg capsules were found in an egg-mass. An egg capsule was 0.53-0.57 mm in size. An embryo (veliger larva) hatched from an egg capsule. Percentage of first sexual maturity in females and males were over 50% for individuals that are 40.1-45.0 mm in shell radius, and 100% for those that are over 45.1 mm. The sex ratio of female to male was significantly different from 1:1 $(x^2\;=\;57.22,\;p\;<\;0.05)$.