• Korean Journal of Weed Science
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• v.8 no.1
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• pp.33-36
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• 1988

The emergences of Echinochloa glabrescens, Monochoria vaginalis, and Cyperus difformis seeds were little affected by fertilizer application. All shading treaments resulted in decrease in emergence of E. glabrescens, while shading up to 67% slightly stimulated emergence of M. vaginalis and C. difformis. The peak emergence of E. glabrescens was at two week after sowing in the full sunlight, 31, and 52% shading, but no peak emergence at the 67% shading. Emergence peaks of C. difformis were observed during 6 to 8 weeks after sowing for all shading levels employed.

• Korean journal of applied entomology
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• v.39 no.4
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• pp.245-250
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• 2000

These studies were conducted to investigate the effect of temperature on the development and seasonal occurrence of Chrysopa pallens Ramber, a predator of aphids. Mean developmental periods of C. pallens from egg to adult emergence at four different temperatures of 17, 22, 27, and $30^{\circ}C$ were 39.5, 32.0,25.0, and 19.8 days, respectively. The longevities of adult females of C. pallens at the four temperatures were 84.7, 79.6, 77.7, and 69.8 days, respectively, whereas the total numbers of eggs laid by a female were 973, 1085, 1637, and 1735, respectively. Egg hatchability, rate of adult emergence, and sex ratio of C. pallets were slighty higher with increased temperature with 84.1~95.9%, 67.6~86.3%, and 1:1. Under three humidity conditions of 35, 55 and 75% RH, the mean developmental periods of C. pallets from egg to adult emergence at the $27^{\circ}C$ were 26, 24, and 22.9 days, respectively, while the number of eggs laid by a female were 1042.8, 1526.5, and 1640.0, respectively. Oviposition of C. pallets usually began 5~6 days after the emergence at $27^{\circ}C$. Then females laid ca. 30~40 eggs a day, reaching a peak of 80~90 eggs a day about 22~28 days after the emergence. Population fluctuation of M. persicae and A. gossypii showed the highest peak in late May through the mid-June, and the second peak appeared in early~mid-September. The adult occurrence of C. pallens by the light trap record started from mid-May, and show two peaks, in mid-late July and mid-late September in Chonbuk area.

• Korean Journal of Ecology and Environment
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• v.33 no.3 s.91
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• pp.267-273
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• 2000

Temperature-associated emergence patterns for a hydropsychid caddisfly, Hydropsyche kozhantschikovi, were studied from the Wangsuk creek in Kyonggi-do from April to June in 1999. Emerging adults were quantitatively collected by pyramidshaped emergence traps. Water temperature was hourly monitored in 1999. The emergence began at April 15 when the daily mean water temperature rose to ca. $10^{\circ}C$: it rapidly increased and peaked in ca. 10 days, and continued to May 25, lasting 40 days since the starting date. The average number of emerged adults was $35.8\;inds./m^2$ and their sex ratio was male (M) : female (F) = 1 : 2.04. The emergence of males was ca. 2 days earlier than that of females. Daily, the emergence was a bigeminans pattern representing the major peak (66.7%) just after dark ($19:00{\sim}21:00$) and theminor peak (11.1%) just before dawn ($05:00{\sim}07:00$). According to our degree dayaccumulation (DD) model, it respectively required 453.89DD (M: 440.48DD and F: 473.97 DD), 615.71DD (M: 610.18DD and F: 622.09DD), and 820.24DD (M: 828.25DD and F: 804.71DD) to begin, to reach the peak, and to finish the emergence.

• Korean journal of applied entomology
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• v.18 no.3 s.40
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• pp.127-132
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• 1979

This experiments were performed to investigate the temperature effects, which caused by the various types of collecting trap treatments, during the overwintering period of pine gall midge larvae, on the peak adult emergence time. And the following results were obtained. 1) The maximum temperatures inside of the collection traps were significantly different each other, and the vinyl cage showed the highest degree which highering $15^{\circ}C$, and standard cage, cage-50 and funnel trap highering $3-12^{\circ}C$ in monthly average comparing to control. 2) There was no significant difference among the treatment in minimum temperatures, during the overwintering periods of larvae. 9) The peak adult emergence time were May 15 in vinyl cage plot which shortened 20 days and both standard cage and cage-50 shortened 14 day than that of control. 4) The funnel type trap treatment delayed 6 days of the peak adult emergence comparing to control, in spite of the treatment showing higher maximum and cumulative temperatures than the control plot. 5) The decadal maximum temperatures of middle part of December and March were significantly correlated with the shortening of the peak adult emergence date.

• Korean journal of applied entomology
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• v.25 no.1 s.66
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• pp.11-16
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• 1986

Local difference in post-overwinter developmental periods was investigated by incubating the overwintered larvae collected from 8 locations at $25^{\circ}C$ begining January 15 and February 15. Based on the 2nd incubation test, it was found that Chunseong colony had the shortest pre pupal period of 17.9 days, while Gwangsan colony had the longest 27.7 days. In general, prepupal period showed negative correlation with latitudes. Average pupal periods were not significantly different among colonies. Adult emergence period showed the same trend as prepupal periods. Chunseong and Pyeongtaeg colonies emerged faster than the other colonies and showed a single peak of adult emergence, while Nonsan, Iri, Gwangsan colony showed several peaks of adult emergence.

• Korean journal of applied entomology
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• v.30 no.4
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• pp.249-257
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• 1991

Chronological changes in the occurrence pattern of the striped rice borer(SRB), Chilo suppressalis Walker, were investigated by analyzing the data collected by 33 light traps of the countrywide monitoring units during the period of 1968-1989. And also relation of incidences between larval and adult populations, emergence time and percent emergence of overwintered larvae were observed in relation to the time of different rice transplantations. Spring moths of SRB in 1985-'89 generally emerged earlier than in 1968-'72 : 30 days earlier at Kwangju, 20 -25 days earlier at Sangju and Naju, 10-15 days earlier at Uljin, Jinju, Goyang, Milyang, Kimhae, etc., 5 days earlier at Suweon, Jinchun, Daejeon, Namweon, Haenam, etc. There was no change in the time of spring moth emergance at Weonseong, Chungju, Seosan, Yongju, and Nonsan. Summer moths of SRB in 1985- '89 also emerged earlier than 1968- '72: 20 days earlier at Uljin, 15 days earlier at Chungju, Yeongdug, and Habchun, 5-10 days earlier at the other areas except Yeongju. There was an overall countrywide decrease in the population of the 1st generation of SRB during the last two decades. The population of the 2nd generation also decreased in 19 areas during the same period, but increased in 14 areas including over 3-fold increases in Kwangju, Naju and Daegu, and double increase in Jinju, Milyang and Gongju. The higher larval population density of 1st genration was taken place in the earlier transplanted fields, whereas the population of 2nd generation were higher at mid-season transplanted (May 30), followed by May 15, June 15, and April 30. The peak of larval population appeared generally 15 days after moth peak in 1st generation, and 10 days after moth-peak in 2nd generation. The earlier transplanted fields were the higher percent damage due to 1st off-springs of spring moths, whereas the fields transplanted in mid-season were higher damage due to 2nd off-springs of summer moths. Average body weights of SRB larvae before overwintering were 65.6 mg, 61.2 mg, and 55.5 mg in early, mid-season, and late transplantations, respectively. In field cage experiments, emergence rate of the overwintered larvae ranged from 28.3-39.8%. In other words, body weights of overwintering larvae were heavier in fields by earlier transplantation, and heavier larvae showed higher percentage of adult emergence. The period from overwintered larvae to adult emergence was longer in the fields of the later transplantations; namely, 44, 49, and 51 days for early, mid-season, and late transplantations, respectively.

• Korean journal of applied entomology
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• v.38 no.3
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• pp.231-240
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• 1999

The long-term tend an pattern changes of Chilo suppressalis(Walker) occurrence in Suwon were analyzed and the forecasting models for spring emergence of C. suppressalis in Suwon were developed. From 1965 to 196, the population dynamics of C. suppressalis in Suwon shows a cyclic fluctuation with one large peak an one small peak, and its periodicity was ca. 36 generations(18 years). C. suppressalis population dynamics in Suwon was characterized as controlled by the endogenous dynamics dictated by the 1st order negative feedback mechanism (fast density dependence). The dynaics mechanism of C. suppressalis populations was not changed although its population density decreased drastically over the years. Using th dta of C. suppressalis spring occurrence in Suwon, forecasting models for spring emergence of C.supressalis were developed based on temperature-dependent development model or degree days. In general, these models well described the C. suppressalis spring emergence pattern in Suwon. Also, forecasting problems in spring moth emergence related with C. suppressalis population dynamics were discussed.

• Journal of the Korean Society of Tobacco Science
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• v.5 no.1
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• pp.11-17
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• 1983

The tobacco moth, Ephestia elutella Hubner (Lepidoptera: Pyralididae), was first reported one of the serious of stored tobacco in Korea in 1939 (8). In recent years, tobacco moth lavae were observed infesting in all of the tobacco storage warehouses in this Country. Adults of the tobacco moth for the seasonal occurrence were studied in the three and four regions in 1981 and 1982, respectively. This species was caught from early May to late October in all regions for both years. In 1981, the first emergence peak was in late May to late at Andong, early June at Suweon and the second one in middle August in both regions. In 1982, on the other hand, there were three peak times, late May and July, and middle September. But the relate size of the peaks was different in two years; the second peak showed about 66% of the total number of tobacco moths captured in the whole year in 1981 at Suweon and 59% of those at Andong, while the first peak had 32% at Suweon and 57% at Shintanjin in 1982. This difference in relative peak sizes was discussed.

• Journal of Korean Society of Forest Science
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• v.26 no.1
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• pp.43-47
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• 1975

Forecasting of emergence period of the pine gall midge (Thecodiplosis japonensis U. et I.) is important for the chemical control of the pest. In order to determine the phenosignal of the emergence period of the pine gall midge, the flowering time of black locust (Robinia pseudoacacia L.) at Seoul, Gwangnug, Jounju and Gyungju districts in Korea was investigated. 1. The emergence period of the pine gall midge lasted from end of May until end of June. The emergence of the pine gall midge coincided with the beginning of flowering of black locus at every districts in Korea. 2. The peak of emergence of the pine gall midge lasted from the full blooming period until the end of the flowering period of the black locust. 3. The period of adult emergence of pine gall midge was also found to be associated with the full blooming period of Viburnum sargentii (Caprifeliaceae). Rosa mulliflora (Reseaceae) and Iris ensata (Iridaceae) at Seoul in Korea.

• Korean journal of applied entomology
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• v.27 no.2
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• pp.103-110
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• 1988

The behavior and circadian rhythm of emergence, copulation and oviposition in the Oriental tobacco budworm (Heliothis assulta Guenee) were studied to obtain the following results. More than three quarters of adults emerged within 3 hours after the light-off. It took about 33 min for an adult to expand and tan its wings after emergence. Adult male showed a sequential pattern of mating behavior, such as antennal movement, wing elevation and vibration, exten¬sion of hairpencils, and tapping of female ovipositor leading to a copulation. However, adult female revealed a rather simple behavior, such as protraction and retraction of her terminal abdomen and vibration of wings. All of the mating took place during the early part of the scotophase, with the peak from 1 hr to 2 hrs after the light-off. But the mating peak in virgin females tended to advance with age. Adult females showed the highest rate of mating among 24 hr-olds and the rate declined with age. The rate of first matings in males gave a very similar pattern to that of females. The duration of copulation was $77\pm$14min. Oviposition occurred throughout the entire scotophase, with the peak during the first 2 hrs. The most nu¬mber of eggs deposited daily was seen on the 3rd day after the mating. Mating rate, number of eggs laid and longevity we~e compared under different sex ratio. Unmated adults lived longer than mated adults.