• Korean journal of applied entomology
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• v.19 no.4 s.45
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• pp.243-248
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• 1980

Experiments were conducted to study on bionomics and control of cutworms; Agrotis tokionis, A. ipsilon, A. fucosa in Suweon, 1978-1979. A. ipsilon and A. fucosa had two or three generations and A. tokionis had one generation a year. A large number of A. toikonis occured at the end of September, and the major peaks of the first generation of A. tokionis and A. fucosa were in mid-June, the second generation in mid-August, and the third generation was at the end of September. These cutworms laid many eggs on the lower surface of curved downward leaf of Chinese cabbage and the larvae later than 3rd instar began to cut the basal part of stem and then pulled into the soil. A parasite of A. tokionis, a braconid wasp, Meteorus rubens, and two unidentified Ichneumnid wasps were found. Mocap and Volaton gave effective control to the cutworms but Volaton should be applied not to contact with plant.

• Korean journal of applied entomology
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• v.19 no.4 s.45
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• pp.187-192
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• 1980

This study was carried out to investigate the bionomics of Ostrinia furnacalis $(Gu\grave{e}n\grave{e}e)$ in the laboratory and field in 1978. The oriental corn borer had three generations a year in Korea ana the first period of moth activity was mostly from early June to early July, the second from mid July to mid August and the third from mid August to early September. It overwintered with larval stage in the corn stubbles. The egg period was 3-4 days. The larva molted 5-6 times and its period was 18-30 days. The longevity of adult was 7-11 days and deposited about 600-800 eggs. An egg parasite and two larval parasites were investigated.

• Korean journal of applied entomology
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• v.31 no.4
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• pp.492-495
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• 1992

Life cycle of the mirid predator, Cyrtorhinus lividipennis, was observed on the constant temper¬ature. Egg periods were 14.43, 9.33 and 6.94 days at $20^{\circ}C$, $25^{\circ}C$ and $30^{\circ}C$, respectively. Nymph periods were 24.3, 14.42, and 11.90 days at $20^{\circ}C$, $25^{\circ}C$ and $30^{\circ}C$, respectively and fe¬male longevity was 11.20, 11.93 and 11.87 days at above temperatures. Relationships between constant temperature and the developmental velocity of egg, nymph and egg-nymph were lin¬ear over temperatures tested. The calculated threshold temperatures of development were $10.7^{\circ}C$ in egg, $9.8^{\circ}C$ in nymph and $10.2^{\circ}C$ in egg-nymph. Total effective day-degrees were 133.9 in egg, 235.8 in nymph and 368.0 in egg-nymph. Number of eggs laid was 26.0 and 22.4 at $24^{\circ}C$ and $30^{\circ}C$, respectively.

• Korean journal of applied entomology
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• v.32 no.1
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• pp.83-89
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• 1993

This study investigated seasonal occurrence, host preference and developmental characteristics of E. lagerstroemiae was most likely to have two generations a year with first occurrence of adults form late April to late may and second from late August to late October including 2 peaks in early May and late August, respectively. Overwintering stages were mostly eggs and larvae and its composition rate was 57.1% of eggs and 42.9% of larvae. Host plats investigated were 7 species 7 families and most preferred species were Lagerstroemia japonica and Diospyros kaki. As morphological characteristics of E. lagerstroemiae, sized of length/sidth were 0.29/0.16 mm for the egg. 0.41/0.16 mm for the first instar larva, 0.96/0.47 mm for the male adult. Number of eggs deposited per female adult was 221.9 individuals. Hatching rate at various temperatures was above 90% at below $30^{\circ}C$. Egg periods were also short\ened with increase of temperatures at below $30^{\circ}C$ but decreased to 56.3% at $35^{\circ}C$. Egg periods were also shortened with increase of temperatures at below $30^{\circ}C$. Hatching rate was not affected by photoperiods but egg periods were shortened with increase of day length.

• Korean journal of applied entomology
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• v.26 no.1 s.70
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• pp.13-23
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• 1987

This study was conducted to know the effects of temperature conditions on the growth and oviposition of the brown planthopper(BPH), Nilaparvata lugens $St{\aa}l$. Results obtained were to predict the timing of the BPH control by measuring population dynamics of the BPH in response to temperature fluctuations upon migration of the insects in paddy fields. Developmental and ovipositional rates under constant and alternating temperature conditions were observed in a plant growth cabinet. Hatchabilities of eggs of the BPH were the highest at $25^{\circ}C$ and were decreased below or above the optimum temperature. Egg periods were the shortest at $27.5^{\circ}C$ and prolonged with decreasing temperature, but retarded at higher temperature above $30^{\circ}C$. Adult emergence rates were the highest at $27.5^{\circ}C$ and reduced with decreasing temperature, and no adult emerged at $32.5^{\circ}C$ and $35^{\circ}C$. Developmental period of nymph was the shortest at both $27.5^{\circ}C$ and $30^{\circ}C$, but extended with decreasing temperature. Female longevity was increased with decreasing temperature and the male longevity was the shortest at $27.5^{\circ}C$. Preoviposition period was the shortest at $32.5^{\circ}C$, but prolonged with decreasing temperature. It was about 6.5 times longer at $17.5^{\circ}C$ than that at $32.5^{\circ}C$. Number of eggs oviposited per female was the greatest at $25^{\circ}C$, but decreased at the temperature below or above the optimum. Under the same total effective day-degrees, hatchabilty at the alternating temperature was about 10% higher than that at the constant temperature but egg period at the alternating temperature was nearly identical as that at the constant. Under the $22^{\circ}C$ condition, emergence rate was about 8% higher at the alternating temperature than that at the constant, however, at the $28^{\circ}C$, the rate was about 8% higher at the constant than that at the alternating. Nymphal period was about $4{\sim}6$ days longer at the alternating temperature than that at the constant. Under the same total effective day-degrees in adult stage, both longevity and oviposition period were longer at alternating temperature than those at the constant. Number of eggs oviposited per female was also higher at the alternating. Longevities of females reared under $28^{\circ}C$ of constant temperature was the longest no matter what temperatures they were exposed after the emergence. This result seems to be indicating that female longevity is greatly influenced by the temperature to which they were exposed durings immature stages. Preoviposition period was affected by the temperature exposed during the nympal and adult stage whereas the number of eggs oviposited was affected by the temperature during the adult stage only. Based on the results from this study, the developmental threshold temperatures seem to be $14.12^{\circ}C$ for eggs, $14.76^{\circ}C$ for nymphs, $9.62^{\circ}C$ for adults, and $15.95^{\circ}C$ for preoviposition period. Estimated values of the total effective temperature for completing each stage were 141.25 day-degrees for eggs, 167.83 day-degrees for nymphs, 349.64 day-degrees for adults, and 58.60 day-degrees for preoviposition.

• Korean journal of applied entomology
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• v.42 no.4
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• pp.323-327
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• 2003

Morphological characteristics and life cycle of Parnara guttata were studied from 2001 to 2002. Egg was hemisphere-shaped in pink. Larva was milky white or yellowish green color with 2.9-30.6 nm body length, depending on their developmental stages from 1 st to 5th instar. Pupa were grayish brown from 23.8 to 25.7 nm length, adults were yellowish brown color and body lengths were 17.4 nm and 16.2 nm and wing expanse lengths were 35.2 nm and 30.6 nm with female and male, respectively. At 25${\pm}$2$^{\circ}C$, each developmental periods was 4.5, 30.2, and 6.9 days with egg, larvae, and pupae, respectively. Also adult longevity were 10.1 for female, average number of egg was 205.5.

• Korean journal of applied entomology
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• v.42 no.2
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• pp.169-171
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• 2003

The life history and natural enemies of Coleophora obducia Meyrick which is a defoliating pest of Larix leptolepis were studied mainly in Chungchongbuk Province. Larix leptoiepis was the only host plant of this pest. Coleophora obducia had one generation per you and the adults emerged from mid May to late May with a peak emergence around May 14th. The mean number of eggs in an ovary was 44.5 and most females oviposited one egg on each needle. The duration of the egg stage was about two weeks. Larvae passed the winter in a pouch made by spinning the needles. Pupation began in the late April, and the pupal period was two weeks on average. The natural enemies observed were parasitoids and predators.

• Korean journal of applied entomology
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• v.34 no.1
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• pp.65-69
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• 1995

This study was carried out to investigate the development and fecundity of Liriomyze chinensis under different temperatures. Egg periods were 4.5, 2.9 and 1.9 days, larval periods 12.7, 5.8, 4.5, days, pupal periods 20.1, 16.3 and 13.0 days, and total development periods from egg to adult emergence were 32.5, 25.0 and 19.4 days under 20, 25, $30^{\circ}C$ of constant temperatures, respectively. Based on this results, developmental threshold temperatures were calculated as 13.0, 11.0 and $7.2^{\circ}C$ and total effective temperatures as 33.0, 86.1 and 293.6 degree-days for egg, larva and pupa, respectively. seventy-eight% of the tested files emerged within four hours and a half after lighting, and none was emerged after eight hours and a half. The longevities of male and female were 5.0 and 8.5 days and the female fly laid 165.8 eggs with her life and punctured 983.8 stipples at $25^{\circ}C$.

• Korean journal of applied entomology
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• v.29 no.3
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• pp.165-169
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• 1990

A study was carried out to investigate some biological characteristics of Pseudogonatopus nudas, a nymphal parasitoid of the whitebacked planthopper (WBPH) under laboratory conditions (26-$28^{\circ}C$). Developmental periods of eggs, larva, prepupa and pupa were 2.5, 7.8, 2.7, and 14.2 days in average, respectively. Total developmental period from egg to adult emergence was average of 27.2 days. More than 83.5% of the wasps emerged in the morning between 6 and 10 o'clock, while very few emerged in the afternoon. The average longevity of female and male were 11.8 and 3.4 days when honey and WBPH nymphs were supplied as food. female laid an average of 25.3 eggs and the oviposition period was 5.4 days. The parasitoid seemed to prefer the 3rd instar nymphas as the host for oviposition with 68.8%, followed by the 2nd (19.6%), 4th (11.05) and 5th instar (0.6%). And no parasitism was recorded from the 1st instar nymphs and in adults.

• Korean journal of applied entomology
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• v.19 no.2 s.43
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• pp.97-101
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• 1980

Present studies were carried out to investigate the life history of potato tuber moth, Phthorimaea operculella (Zeller), under laboratory conditions in Suweon. Studies on its life-cycle on stored potato tubers in the laboratory showed that seven generations were reared in a year and the development from egg to adult was completed in an average of 49.4 days in spring at $18.2^{\circ}C$., 21 days in summer at $26.8^{\circ}C$., 26.1 days at $24.2^{\circ}C$., and 39 days in autumn at $19.6^{\circ}C$. The females laid an average of 101 eggs each, with a maximum of 242 and longevity of adults 17.6 days in spring at $15.1^{\circ}C$., 8.1 days in May-September at $25.3^{\circ}C$., and 13.3 days in autumn at $16.8^{\circ}C$.