• Korean journal of applied entomology
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• v.50 no.1
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• pp.1-6
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• 2011

Movement of adult Monochamus alternatus was investigated on young black pine, Pinus thunbergii, trees for about one month in a screen cage. Number of pine trees to which M. alternatus females and males moved during the experimental period was $6.4{\pm}1.4$ and $7.2{\pm}1.5$ out of 15 trees, respectively. Adult females and males moved to $0.2{\pm}0.1$ and $0.3{\pm}0.1$ tree per day, respectively. A 74.6 and 80.7% of adult females and males moved at night (17:00-08:00) to other trees. After moving, most beetles (72.6% of females and 76.0% of males) stayed on the tree to which they moved for one to two days. Some beetles stayed for up to seven days.

• Journal of Aquaculture
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• v.20 no.3
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• pp.190-193
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• 2007

Viability, early growth and sex ratio of induced gynogenetic diploid bagrid catfish (Leiocassis ussuriensis, Siluriformes) were examined. Survival rates of gynogenetic diploids and normal bi-parental diploids up to 180 days post hatching were not significantly different (P>0.05), and consequently resulted the mean percent survivals of 76% (gynogens) and 78% (bi-parental progeny) at the end of growth trial. Growth in both body weight and total length of gynogenetic diploids was also similar to those of normal diploid controls (P>0.05). Gynogenetic bagrid catfish displayed a similar level of ovarian development when compared to bi-parental diploid females, as judged at 10 weeks post hatching. Sex ratio of bi-parental progeny was normal 1:1 whereas all-femaleness was observed in gynogenetic progeny (P<0.05), suggesting that the genetic sex determination mechanism of this species should be XX-XY based female homogamety.

• Journal of Aquaculture
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• v.6 no.4
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• pp.285-293
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• 1993

Gynogenetic diploid of olive flounder, Paralichthys olivaceus were induced by cold shock to fertilized eggs with red sea bream, Paragus major sperm that had been genetically inactivated with 4,800 ergs/$mm^2$ ultraviolet (UV) rays. Cold shock to the eggs at $2^{\circ}C$ for 45 minutes proved to be optimum condition to retain the second polar body. At this treatment, hatching rates of normal fry obtained were more than $33.8\%$. No different growth rates were observed up to 200 days after hatching between control and gynogenetic diploid offsprings. However, body weights of gynogenetic diploids were significantly heavier than that of control 300 days after hatching (p> 0.05). A proportion of female in gynogenetic diploid was significantly higher than that in the control (p< 0.01).

• Korean journal of applied entomology
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• v.41 no.1
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• pp.61-65
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• 2002

This study was conducted to investigate percentage of parasitism and control effect of Liriomyza trifolii by Hemiptarsenus zilahisebessi on tomato. Percentages of parasitism on L. trifolii larva by ectopatasitoids war e 26∼45% Among them the parasitism by H. zilahisebessi was highest as 47∼75% in tomato. The parasitoids preferred 1 st to 3rd instar of host larvae. In laboratory test, the parasitoids showed high parasitism on 3rd instar larvae of host by 89.8∼93.1% when the female parasitoids were introduced by the ratios of 1 : 10, 1 : 20, and 1 : 30. In field test, 3 or 5 female parasitoids were introduced per plant. In the case, the parasitism increased to 80% 4 weeks after introduction of the parasitoids. This increased parasitism was resulted from density reduction of the host larvae There were no significant differences in parasitism, density of alive host, and percentage of damaged leaf between inoculation density.

• Korean Journal of Ichthyology
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• v.35 no.4
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• pp.333-339
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• 2023

The aim of this study was to collect information regarding the sex ratio, size at sexual maturity, and the primary spawning period of Hexagrammos otakii. The sex ratio (female : male) was observed to be 1 : 1.2 (n =739 : 906, with females comprising 81.6% of the population). The gonadosomatic index (GSI) exhibited its highest values in November for females and October for males, coinciding with the primary spawning period from November to January. The total length required for 50% sexual maturity was determined through a logistic regression model and found to be 23.1 cm for females.

• Korean Journal of Environment and Ecology
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• v.26 no.1
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• pp.57-66
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• 2012

This study was conducted to investigate the reproductive ecology of the Korean Mandarin Fish, Siniperca scherzeri in Seomjin River and Imjin River from April to October 2008. After have investigating the relationship between standard length (SL) and Gonadosomatic index (GSI) of Siniperca scherzeri, we can conclude that the body length of maturation was over 200mm SL in case of females and over 180mm SL in males. The GSI of the females that were from Seomjin river was the highest in April (7.43%), and gradually decreased after May (5.55%) and June (3.58%). The GSI was decreased sharply in August and indicated the lowest value in September (0.44%). The GSI of the females that were from Imjin river showed similar tendency of females' GSI from Seomjin river. The GSI of males from Imjin river was totally higher than that of females, it was 5.96% in April, and 8.03% in May. It was lowered in early June, and late June, it indicated 2.12%. In September, it was the lowest value (0.20%), and increased after October (0.54%). The result of histological study of ovary presented similar result of the study of GSI in Seomjin river and Imjin river. The ratio that fishes constitute in stomach contents of Siniperca scherzeri was 92% in Seomjin river and 90% in Imjin river. Digestion of food organisms and the ratio of unidentifiable fishes in stomach contents was fairly high, and it was 50% in Seomjin river and 72.2% in Imjin river. In the period of study, eating ratio was very low 38.3% (36 ind.) in Seomjin river and 21.8 (53 ind.) in Imjin river.

• Korean journal of applied entomology
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• v.33 no.1
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• pp.26-32
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• 1994

Electroantennography, wind tunnel observation, and field trapping experiments were carried out to investigate the biological activity of synthetic sex pheromone in the onental tobacco budworm. Heli-couerpa assulta. Two major sex pheromone components of H. assulta, Z9-16' Ald and Z11-16: Ald. elicited a big EAG response in male, but not in female Their mIXture ratios did not give much influence on EAG size Fema]e H assulta showed a great EAG response only to its host plant e extract. EAG size also increased with the amount of mixture from 001 to 10 [lg but rather decreased w when the amount was 1 00 $\mug$. H. assulta always revealed a series of stereotyped behavior in a wind tunnel. The behavioral response was different when the males were stimulated with the sex pheromone containing some minor components, 16: AId and Z9.16: Ac, or being different in mixing ratios of the two major components. The best ratio of the sex phemmone components for a attracting H assulta male adults was 20-25: 1 between Z9-16: Aid and Z11-16: Ald in net house a and red pepper field experiments in Korea When the lure contamed Z9-16: OH, attracting power rapidly decreased. The synthetic sex pheromone showed a strong attraction when compared to virgin females

• The Korean Journal of Malacology
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• v.25 no.2
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• pp.173-178
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• 2009

The bigfin reef squid, Sepioteuthis lessoniana is commercially important species in Korea. Korean fishing vessels have actively caught it. However, the reproductive Biology of this species has been poorly known. Therefore, the purpose of this study is to provide information on the reproductive biology of Sepioteuthis lessoniana in Jeju Island, Korea. The bigfin reef squid caught by set net, from June to November 2006. Monthly changes in maturity stages, gonad weight, mantle length at 50% group maturity and sex ratio were investigated. The mantle length of the bigfin reef squid was between 10.6 and 32.1 cm. Maturation and spawning occur all year around, with more intensity from July to September, with peak July. The spawning period was June. The mantle length at 50% group maturity was estimated to be 18.01 cm. Sex ratio was 1:1.4 (male:female). The proportion of female was significantly higher than male ($x^2$-test, p > 0.01).

• Korean journal of applied entomology
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• v.41 no.4
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• pp.263-267
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• 2002

A faunistic survey was conducted to find Osmia bees to be used as an effective pollinator in apple orchards. Collections were carried out from more than 50 selected sites in mountainous areas throughout Korea for 3 years (1996-98) with providing bundle of bamboo traps (6-8 mm of inner diameter) as Osmia nesting site. Five species of Osmia ：O. cornifrons (Radoszkowsky), O. pedicornis Cockerell, O. taurus Smith, O. satoi Yasumatsu et Hirashima and O. jacotti Cockerell, were collected at the rates of 39.9-51.7, 28.3-53.7, 5.5-19.1, 0.8-0.9 and 0.0-0.1%, respectively. And O. cornifrons and O. pedicornis were the dominants with over 80% of total Osmia collected through the collections. Out of those bees collected, rates of female were 29-43% for O. cornifrons. 10-12% for O. pedicornis and 22-43% for O. taurus. When the collection sites of the dominant 3 species were grouped in relation to altitudes above the sea level, about 50% or more bees were collected form the higher sites (500m or higher) while 20% or less were from the lower sites (200m or lower). When the bamboo traps were placed at the same sites continuously for 3 years, number of O. cornrfrons and O. taurus collected was slightly increased while that of O. pedicornis was drastically decreased year after year. Nesting by Osmia bees seems to have started at around early April, peaked at early May and ended by Mid June, while nest competing species of Sphecidae and Eumenidae started nesting at around early June, peaked at early July and ended by the Mid August.

• Korean Journal of Environment and Ecology
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• v.28 no.5
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• pp.550-558
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• 2014

This study was conducted to investigate the distribution and the population dynamics of Hipparchia autonoe by using a line transect and Mark-Release-Recapture (MRR) at the Mt. Halla in Jeju Island. The results showed that H. autonoe was found from 1,500 m above the sea level. Total 1,493 H. autonoe with 978 males and 515 females were captured and released in the MRR study site. Among them, 518 individuals including 284 males and 234 females were recaptured. The average survival time was 2.31 days with 2.14 days for males and 3.47 days for females, indicating longer survival time in case of females than males. The daily population size of males estimated in the MRR study site was maintained about 1,000 individuals in July and gradually decreased less than 200 in August. The number of females showed peak at 335 individuals on July 24, and gradually decreased less than 120 in August. Thus, female population was 1/3 of males. The average travel distance of male and female H. autonoe were $116.8{\pm}191.9m$ and $118.4{\pm}161.5m$, respectively, indicating almost same between sexes. H. autonoe in the Mt. Halla formed single population group in the wide meadow around the Baekrokdam Lake. The highest population density of H. autonoe was occurred in the restored area from damages, where host plants such as the sheep's fescue or the food plant are abundant by artificial restoration efforts.