• Korean journal of applied entomology
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• 제48권1호
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• pp.101-108
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• 2009

For biological control of larva of Cnaphalocrocis medinalis and Naranga aenescens do considerable damage to crops by folding and scraping the leaf tissue of rice, a large number of Bacillus thuringiensis isolates have been obtained from soil samples in Korea and the pesticidal activity was assayed against two insect pest species described above. Among 53 Bt isolates tested in bioassay, 18 and 13 isolates showed over 90% mortality against C. medinalis and N. aenescens, respectively. Some isolates (11 isolates including CAB141) presented dual activity against C. medinalis and N. aenescens. These isolates showed over 96% control effect in pest control in laboratory against larvae of C. medinalis. Also, it was investigated that pupation, pupal length, and adult emergence of larvae exposed to Bt suspension decreased. Especially, the pupal length of C. medinalis after being fed corn seedling leaves treated Bt suspension for 10 days, were much smaller than that of control.

• Korean journal of applied entomology
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• 제39권2호
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• pp.73-82
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• 2000

Two Psyllidae species of Cacopsylla pyricola (Foerster) and C. pyrisuga (Foerster)damaging pear trees have been reported in Korea. However, their ecological characteristics and damagepatterns have not been evaluated yet. To establish basic control measures of C. pyricola, field phenology,overwintering ecology, seasonal fluctuation and temperature-dependent development of C. pyricola wereexamined. C. pyricola overwintered under the bark scale of pear trees as winter form adults and theymoved to fruiting twigs from mid-February. Honeydew produced by C. pyricola nymphs and adults asthey feed caused serious black sooty mold on leaves and fruits. The seasonal occurrence of C. pyricolawas different every year. In 1993, characterized by cold temperature and heavy precipitation, C. pyricolapopulation was maintained highly during growing season. However, the population was decreased rapidlyfrom early July in 1994, year of hot and dry weather condition. In 1995, year of average temperature, thedensity of C. pyricola population was decreased during hot months of July and August, and rebuilt up inSeptember and October. The development periods of C. pyricola eggs were 13.33 days at 15"C, 9.32 daysat 20$^{\circ}$C, 7.82 days at 25"C, 6.60 days at 30$^{\circ}$C, and 7.75 days at 35$^{\circ}$C. The development periods ofnymphs were 33.75 days at 15OC, 23.77 days at 20$^{\circ}$C, 15.21 days at 25"C, and 17.40 days at 30$^{\circ}$C. Theirdevelopment periods and mortalities were increased in higher temperatures. The parameters of nonlineardevelopment model, Weibull and linear development models of Cacopsylla pyricola were estimated.models of Cacopsylla pyricola were estimated.

• Journal of the Korean Wood Science and Technology
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• 제43권6호
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• pp.804-809
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• 2015

Since Korea is home to Reticulitermes speratus, a kind of subterranean termites that prefer dark and humid conditions, there have been increasing damages to wooden structures by termites. One noticeable attribute of Korean subterranean termites is that they prefer than Pinus densiflora, the major construction material for Korean traditional houses. And because wide varieties of termites are distributed all over the world, it is not so easy to choose appropriate control methods depending on specific areas. This necessitates careful applications of the following control methods depending on the kinds of termites: fumigation treatment, soil termiticide, preservatives and insect treatment, termite colony elimination system, chemical treatment, and other physical and biological treatment methods. The purpose of this study is to investigate the control effects of environmentally-friendly Alkaline copper quaternary (ACQ), Copper Azole (CuAZ) and Micronized copper quarter (MCQ) on the termites contributing to the damage of wooden structures. It was found in this study that wood with preservative treatment produced a significantly higher termicidal efficacy than untreated wood.

• Korean Journal of Food Science and Technology
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• 제33권2호
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• pp.184-189
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• 2001

Comparative effects of gamma irradiation and methyl bromide (MeBr) fumigation on water-soluble components of small red bean and mung bean were investigated. The levels of soluble solid and reducing sugar of soaked water at $20^{\circ}C$ for 16 h definitely increased as irradiation dose increased, which was more apparent in small red bean than in mung bean. But, their levels of MeBr-fumigated sample showed a similar result to those of the control, except for soluble solid of small red bean. The pH of soaked water was insignificantly different among treatments. The decrease in lightness (L value) and the increases of redness (a value) and yellowness (b value) were remarkable as irradiation dose increased, which was more significant in fumigated samples. The ${\Delta}E$ values of fumigated sample showed almost equaled to those of 10 kGy in red bean and 30 kGy in mung bean, respectively. Gamma irradiation caused the increase in free amino acids of soaked water, that mainly consisted of asparagine, glutamic acid, and valine, while fumigation reduced their contents. The extractables in soaked water, such as soluble solid and reducing sugar, showed a highly positive correlation with irradiation dose applied.

• Korean journal of applied entomology
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• 제53권3호
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• pp.287-293
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• 2014

Matsumuraeses phaseoli is one of the main pests that attack the flowers and pods of red bean (Vigna angularis) and mungbean (Vigna radiata) in Korea. To elucidate the developmental characteristics and over-wintering stage of M. phaseoli, several stages of the insect were observed through artificial rearing under outdoor conditions in Suwon ($37^{\circ}$16'N $126^{\circ}$59'E 35ASL), Korea. In colonies in which neonate larvae were reared at about 2-week intervals for more than a year, the developmental period from larva to adult emergence became longer from spring to summer, but shorter from summer to autumn; aestivation was not observed during the summer season. The colony in which rearing started on Oct 8, 2008 over-wintered as pupae and emerged in late April next year with a survival rate of 6%. However, the colony in which the rearing started on Oct 23, 2008 over-wintered as mature larvae, pupated in late April, and emerged in early and mid-May with a survival rate of 2%. When the fifth instar larvae were transferred outside from the laboratory ($25^{\circ}C$, 15L:9D) between November and February, no larvae could survive during the winter season. Some newly laid eggs and newly emerged adults could not hatch and could not survive, respectively, in outdoor conditions in November and December. These results suggest that neonate larvae of M. phaseoli that hatch in October can over-winter as late larvae or pupae in Suwon, Korea.

• Korean journal of applied entomology
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• 제54권4호
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• pp.431-435
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• 2015

Riptortus pedestris (Fabricius) is one of the important insect pests of leguminous crops, which occurs in most areas of South Korea. It is hard to distinguish each generation in crop fields since not only the longevity of adult R. pedestris is long but also the developmental period is short. Especially, the 2nd generation adults cause enormous damage to soybean while the occurrence time is synchronized with the podding stage of soybean. Controlling the 1st generation of R. pedestris helps to decrease the damage by decreasing the 2nd generation density. This study was conducted to distinguish between the 1st generation and the overwintering generation by using differences in body coloration which is dependent on the day-length during the nymph stage. In addition, the difference was verified by the population dynamics model of R. pedestris. The occurrence time of 1st generation adults could be considered when the summer form is 20% or more. These results will be used for beneficial management decisions to reduce the 2nd generation population.

• Korean Journal of Social Welfare
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• 제56권3호
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• pp.303-325
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• 2004

This study investigated subtypes of men who batter, and explored the differences among them. It was based on 217 subjects from all around the nation who received legal punishment. In the analysis of the typology, we specifically tested whether the Holtzworth-Munroe and Stuart proposed typology was verified. The results of the cluster analysis revealed support for their theoretical distinction for three types of abusers. These results imply that Holtzworth-Munroe and Stuart's batterer typology is applicable to Korean batterers to some degree. Type 1 men demonstrated the lowest levels of physical and psychological abuse toward their wives and were the least likely to have had a history of child abuse or alcohol problems. These men had lower MCMI scores and did not show any extraordinary personality traits. Men in this category were violent only against their wives, had relatively liberal sex role attitudes and had the most satisfaction in their intimate relationships. Type 2 men were violent only at home, using a moderate level of violence. These men had very high levels of dependency on others and showed a borderline, avoident or passive-aggressive personality. The amount of alcohol consumption was similar to Type 1, but scores of jealousy, self-esteem, and attitudinal variables were similar to Type 3 men. They lacked assertiveness skills and reported the least marital satisfaction. Type 3 men used the most severe violence and were violent both inside and outside the home. These men showed signs of antisocial and aggressive personality. They had experienced frequent physical abuse during childhood, were the most likely to abuse alcohol and had lower self-control. Type 3 were the most traditional in their views of women's roles and had attitudes supporting violence. Based upon the study findings, practical implications of enhancing treatment efficacy were considered.

• Korean journal of applied entomology
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• 제58권3호
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• pp.175-182
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• 2019

The citrus leafminer, Phyllocnistis citrella (Lepidoptera: Gracillaridae), is an important pest that decreases the productivity of citrus trees by attacking citrus leaves, and especially it causes a severe damage during the young growth stage. In this study, we investigated the distribution of eggs on the leaves of shoots according to the position and the survival rate of this pest in the field condition. The occurrence patterns of P. citrella eggs in citrus orchards were largely affected by the occurrence of shoots. Even if the adults were still being attracted in the pheromone traps, the eggs were not observed on leaves when the growth of shoots was stopped. The density of P. citrella eggs in the citrus shoots peaked at the fifth or sixth leaf from the terminal leaf, and over 90% of the eggs were found in the first to eighth leaves as a whole. In 2015 and 2016, the average survival rate of larvae surviving to pupa was 1.4%, and the rate of survival to adults was 0.2%, indicating that most of them died. Furthermore, we have discussed the management strategy of P. citrella considering the distribution of eggs and the larval survival rate in the citrus shoots.

• Korean journal of applied entomology
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• 제58권3호
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• pp.197-202
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• 2019

Jujube tree farms need effective methods of pest control to reduce damage caused by mirid bugs. In this study, we measured the density of mirid bug populations in jujube trees and tested the efficacy of various insecticides. We observed seasonal density patterns, where nymphs were observed from early May to the middle of July; and adults were observed from the end of May to the middle or end of July. Furthermore, we measured the density of two types of mirid bug species, Apolygus spinolae and A. lucorum. Among 45 damaged jujube trees, the dominant species of mirid bugs was A. spinolae (89%). We tested 7 types of insecticides to control mirid bug populations, including pyrifluquinazon, deltamethrin, diazinon, dinotefuran, etofenprox, fenitrothion, and bifenthrin, showing over 80% efficacy. Thus, in this study, we showed that using insecticides was effective for controlling mirid bug populations on jujube trees.

• Journal of the Korean GEO-environmental Society
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• 제12권10호
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• pp.39-49
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• 2011

Recently PBD method, one of acceleration of consolidation methods is used in the soft ground to shorten consolidation time for fast settlement during construction. It is economical and easy to work. Discharge capacity of PBD is sensitive in proportion to thickness of soft ground layer, and drainage of PBD declines due to disturbance effect in surrounding ground by mandrel used for vertical drainage setting and setting machines and type. Also, deviation of discharge capacity is large according to ground condition, construction condition and soil properties. In addition, when embankment loading is not conducted instantly after PBD setting due to rain or lack of embankment material supply, it causes leaving period problems. But cause and analysis of those problems for discharge capacity is lack. So, in this test, ground improvement and discharge capacity is investigated by implementing composite discharge capacity test for analysis of an effect factor of PBD discharge capacity with leaving period. After fixing the vertical drain on a cylindrical cylinder, put churned sample into the cylinder. Then leave 0day, 30day, 60day and 90day. And then, load following the loading step of 30, 70 and 120kPa using a pressure device. As a result, the longer leaving period, discharge capacity is reduced. It is caused by a decrease of discharge area caused by creep transformation moisture absorption of PBD filter after long leaving period.