• Korean journal of applied entomology
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• v.27 no.4
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• pp.200-210
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• 1988

ABSTRACT Brown planthopper collection data by 151 light traps located throughout the southern part of Korean peninsula for 7 years from 1981 thru 1987 were analysed with each immigration wave in relation to daily weather charts when the immigration occurred, and summarized as below. 1) Most of the main immigration took place during the mid and late July, though there were some variations from year to year. 2) Number of the BPH collected at one time, and the number of the area where those immigrants where collected were increased when it occurred closer to the end of July. 3) Weather conditions when the immigration took place were divided into 4 types; (a) depression with stationary front passed over the central peninsula (A type, 12 times); (b) depression with stationary front passed over the southern sea (B type, 5 times); (c) stationary front passed over the central peninsula(C type, 7 times); (d) without depression and stationary front (D type, 2 times). 4) Whatever the types of the weather, those immigrations started to land from south-west part of the peninsula, and those numbers of immigrants were also grater at those south-western areas. 5) When common weather factors were counted from each weather chart of the days when thcse immigrations took place, presence of wind from south-west was 26 times, presence of stationary front was 24 times, and presence of depression was 17 times out of all 26 cases of immigration. 6) Therefore, it could be concluded that the immigration of the BPH into Korea is simply accompanied by the north$.$easterly flowing air currents, connected from south-east part of China through Korean peninsula. And other factors seem to be related with inducing their landing.anding.

• Korean journal of applied entomology
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• v.30 no.3
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• pp.169-173
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• 1991

These studies were conducted to investigate overwintering forms and adult population fluctuation in field condition, and life cycle in field-cage condition of diamondback moth, Plutella xylostella (L.). Plutella xylostella overwintered as all the stages of eggs, larvae, pupae and adults in southern region of Korea. The occurrence which adult moths were attracted by light trap at 5-day intervals, reached their peaks in May, mid-June to mid-July, and late September to early November, and fell in late July to mid-September. Under field-cage condition, they occurred 10-11 generations a year and the period of adult emergence from egg was 11-18 days in July and August, 19-23 days in June and September, 28-34 days in April, May and October, and about 50-100 days in other months. And the longevities of adults were 4-11 days in summer, 7-17 days in spring and fall. A number of eggs laid by individual female ranged from 50 to 240. The females laid more eggs in spring and fall than they did in summer. The period of developmental stages under field-cage conditions was 2-3 days for eggs, 7-8 days for larvae and 4-6 days for pupae in July and August; 4-5 days for eggs, 3-12 days for larvae and 6-8 days for pupae in June and September; 6-18 days for eggs, 13-20 days for larvae and 8-14 days for pupae in March, April, May and October; and 12-40 days for eggs, 50-100 days for larvae, and about 20 days for pupae in winter.

• Korean journal of applied entomology
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• v.54 no.3
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• pp.247-255
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• 2015

The cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae) infests citrus orchards, causing sooty mold damage to the fruits. This study was conducted to investigate the colonizing route of A. gossypii in citrus orchards in a non-heating plastic-film house during the early season. The overwintering eggs of the aphids are frequently found on summer shoots of the citrus trees. The eggs were mostly those of Aphis citricola, without any A. gossypii when hatched. The colonization of citrus trees by alate A. gossypii in non-heating plastic-film houses was mainly observed twice, with advanced flight in late April and delayed flight in late May. The delayed flight was synchronized with the timing of the emergence of alate A. gossypii from the fundatrix generation in the holocyclic life cycle. During advanced flight in closed citrus orchards, alate A. gossypii were caught in yellow water traps installed in the fields, and the populations were found to originate from the surviving populations of the anholocyclic life cycle. Consequently, we concluded that citrus tree colonization with A. gossypii occurred during the advanced flight of the anholocyclic and the delayed flight of the holocyclic life cycle.

• Korean journal of applied entomology
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• v.44 no.3 s.140
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• pp.199-205
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• 2005

Seasonal occurrence and ovarian development of the bean bug, Riptortus clavatus Thunberg (Heteroptera: Alydidae), were studied at a soybean field and an university campus in which host plants are less available for the bug in Gyeongnam province with aggregation pheromone traps in 2004. It was assumed that the bug passed three generations per year at the university campus. Adults of the 1st generation might occur from early July to early August and that of the 2nd one from mid August to late September. Adults of the 3rd generation occurred from early October to mid November, entered reproductive diapause without carrying eggs in the ovaries of females during winter, and resumed activity from late March of the next year. Full-grown eggs in the ovaries of the overwintered females were first observed at the 1st half of May. Two peaks of occurrence, from early August to mid September and from mid October to mid November, were shown at soybean field that was sowed on May 24. The two peaks almost corresponded to those of the 2nd and 3rd generations at the university campus, respectively.

• Korean journal of applied entomology
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• v.44 no.3 s.140
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• pp.225-230
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• 2005

This study was conducted to investigate the developmental characteristics of cabbage armyworm, Mamestra brassicae L. (Lepidoptera: Noctuidae) by different temperatures and its seasonal occurrence in pepper field. Under four constant temperatures, 15, 20, 22 and $25^{\circ}C$, developmental periods from egg to adult were 88.3, 63.0, 52.3, and 42.8 days, respectively, with egg periods being 9.2, 6.2, 5.0 and 3.9 days, and larval periods being 40.5, 30.1, 23.3 and 21.2 days, respectively. Developmental threshold and thermal requirement in degree-days (DD) were $7.9^{\circ}C$ and 69.4 DD for egg, $4.8^{\circ}C$ and 434.8 DD for larva and $6.7^{\circ}C$ and 344.8 DD for pupa. Fecundity of female increased as temperature increased laying 1262.1 eggs at $15^{\circ}C$, 1663.8 eggs at $20^{\circ}C$ and 1763.2 eggs at $25^{\circ}C$. Mean numbers of eggs per egg-mass were 99.4, 114.7 and 167.9 under the three constant temperatures, respectively. In Daegwallyeong highland area, this noctuid occurred from mid June to late August and has two generations a year reaching peak two times, one at late June and the other at early August.

• Korean journal of applied entomology
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• v.23 no.2 s.59
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• pp.96-101
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• 1984

This experiment was carried out to investigate control efficacy by cultural practice and fumigation of tacterial wilt caused by Pseudomonas solancearum in resistant tobacco line NC82 at the Korea Ginseng and Tobacco Research Institute, Eumseong Experiment Station in 1982 and 1983. The bacterial wilt of tobacco occurred severely from mid-July to last August in applicable temperature and soil humidity for increasing bacteria. Disease severity appeared low and slowly at fumigation and resistant variety treatment. Incidence of bacterial wilt in tobacco line NC82 was $44.7\~55.8\%$ being compared with susceptible variety, NC2326 and $95\~99\%$ when resistant variety, NC32 was cultivated with soil fumigation treatment. Control efficacy of cultural practices appeared low with $0.8\~20\%$ and was not different from resistant variety and fumigation treatment. Control system against bacterial wilt in flue-cured tobacco was accomplished by control efficacy over $95\%$ when resistant variety(NC82) was cultured after treatment of cultural practices (Tillering after harvest and before transplanting, stalk and root destruction, early transplanting early removal of the mulching film) and soil fumigation(Cylon).

• Korean journal of applied entomology
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• v.51 no.4
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• pp.449-459
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• 2012

Fruit borers such as Grapholita molesta, G. dimorpha and Carposina sasakii are major pests of plum in Korea. Population densities and seasonal occurrence were monitored using the synthetic sex pheromone trap in Uiseong and Gyeongsan, two important major plum growing area in Korea. In 2010 and 2011, adults of G. molesta were caught from mid April with the peak of late April, and then undergone three more generations in Gyeongsan. Grapholita dimorpha appeared from late April and they showed three peaks until late September. Both Grapholita species occurred a few days later in Uiseong than in Gyeongsan where the latitude is $1^{\circ}$ lower. There was no difference of the phenological occurrence of C. sasakii between Gyeongsan and Uiseong, showing the same patterns of two or three peaks. Population size was in order of G. molesta, G. dimorpha and C. sasakii with 63:16:20 and 47:35:18 in Gyeongsan and 51:18:31 and 46:13:36 in Uiseong, in 2010 and 2011 respectively. There was no difference between the numbers of Grapholita species caught in the trap installed inside and outside of the orchards.

• Korean journal of applied entomology
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• v.51 no.4
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• pp.405-410
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• 2012

This study is conducted to develop a new method of early occurrence monitoring for Aculops lycopersici Massee (Acari: Eriophyidae), a major pest in tomato. A. lycopersici causes damage to plants such as curling of leaflet edges, followed by leaflet bronzing. As feeding continues by the mites, the plant takes on a russeted, wilted appearance, eventually culminating in leaflet desiccation and finally plant death. Fruit damages in tomato were shown when the density of mites was very high. Also, A. lycopersici caused more damage to unripe fruits than ripe fruits. The time taken to detect A. lycopersici on green label sticker was 7.0 seconds, the shortest. Blue, orange and white label stickers took 17.1, 19.8 and 12.3 seconds respectively. The permeable microscope with side illumination was useful in observing A. lycopersici on label stickers. A. lycopersici began to occur in late-April and the density of the mites increased rapidly after mid-May. The density peaked in mid to late-June, and decreased after late-June. A. lycopersici was observed on lower stems 20 days after the release of mites and observed on higher stems 60 days after. The peaked densities were observed on stems 40 and 60 days after and on leaf 80 days after. The label sticker is enough to monitor early occurrence of A. lycopersici in tomato cultivation facilities.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.29 no.1
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• pp.55-62
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• 2007

Radical paring of the cleft edge during primary cleft lip operation or repeated secondary surgeries can result in tightness of the upper lip. In case, the degree of the resulting side-to-side tension is very severe, the possibility of a lip switch flap must be considered. When the lip tightness accompanies a loss of more than two-thirds of the Cupid's bow, an Abbe flap is an alternative. The disadvantages of Abbe flap are scar formation on the lower lip, design of incision line on the upper lip, disharmony of colors, and the dysfunction of the orbicularis muscle. These problems have been recognized in the literature and extreme discretion has been advised in its application. We experienced four cases of Abbe flap operation which were designed differently to correct the secondary unilateral or bilateral cleft-lip nasal deformities. The Abbe flap operations resulted in removal of the scars and tightness of the upper lip, reconstruction of the Cupid's bow, lengthening of the columella, and therefore secondary cleft-lip nasal deformity could be corrected. It is thought that carefully applied Abbe flap is an appropriate method to relieve horizontal tightness or flattening of the upper lip which occured after primary operation of cleft lip.

• The korean journal of orthodontics
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• v.27 no.1
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• pp.45-54
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• 1997

The purpose of this study was to evaluate the indications of bionator in Class II division 1 malocclusion, The 48 subjects were classified into good result group(group1) and poor result group(group2) in reference to posttreatment molar relation, posttreatment overbite and overjet, posttreatment profile, and relapse. Pretreatment lateral cephalograms were calculated and evaluated by t-test stepwise discriminant analysis. The results were as follows ; 1. In jaw bone relationship, ANB, facial convexity angle, AB to facial plane angle were significantly different between two treatment groups. In denture pattern, L1 to facial plane, L1 to A-Pog, FMIA, and U1 to facial plane were significantly different and m soft tissue profile, protuberance of lower lip and upper lip were significantly different between tw o treatment groups. 2. The results in according to discriminant analysis stated that L1 to facial plane, ANB, FMIA and protuberance of lower lip help prediction of treatment result of bionator. 3. 3 major influential variables were obtained by stepwise discriminant analysis - L1 to facial plane, articular angle and ANB difference. And Fisher discriminant function was made by these three major variables.