• Journal of Life Science
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• v.11 no.2
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• pp.121-125
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• 2001

Some attempts were made to investigate the biological characterisitcs of the green rice leafhopper(GLH) , Nepthotettix cincticeps Uhler in terms of nymphal development, emergence ratio. preovipositional period, growth index, adult longevity and fecundity fed on rice cultivar, Chucheongbyeo with no resistance gene and water foxtail, Alpecurus aequalis Sobol. var. amurensis Ohwi at 20 and $25^{\circ}C$ with a 16L;8D photoperiod. Development period of nymph on rice cultivar and water foxtail at $25^{\circ}C$ was shorter than that at 2$0^{\circ}C$ by twofold. The nymphal period of female was about one day longer than that of male. The mean emergence ratio of female and male on rice cultivar and water foxtail was 40.0, 76.7, 38.3, 73.3% at 20 and $25^{\circ}C$, respectively. Preovipositional period on rice cultivar and water foxtail at $25^{\circ}C$ was shorter that at 2$0^{\circ}C$ by twofold. Growth index on rice cultivar adn water foxtail at $25^{\circ}C$was higher than that at 2$0^{\circ}C$ by fourfold. Under the 20 and $25^{\circ}C$ condition, the longevity of female and male was longer on water foxtail than on rice cultivar, but the fecundity of GLH was higher on rice cultivar than on water foxtail. In conculsion, water foxtail seems to be adequate for spring host of GLH.

• Korean journal of applied entomology
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• v.43 no.3 s.136
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• pp.195-200
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• 2004

The occurrence pattern and bionomics of Selatosomus puncticollis (Motschulsky) were surveyed in three net house (6$\times$70m) in the field and in a laboratory ($20^{\circ}C$, RH$75\%$, L16/DB). Emergence of hibernated adults of S. puncricollis started from early May, reached peak at early June and diminished in late June. Occurrence rate to total number was $42.1\%$ in early June and $31.7\%$ in late May, when most of hibernated adults emerged at these periods. Adults started to oviposit from mid June, and eggs hatched from early July Larvae turned into pupae from mid July and emerged to adults from mid August. Egg-period was 23 days and pupal period was 21 days. It is estimated that preovipositional period and larval period were approximately 10 months and 30 months, respectively. Wireworms were distributed at the soil depth of 10-5 cm, $56.8\%$ in 1997 and $45.8\%$ in 1998. To establish bait techniques to attract wireworms in the soil, six baits: pieces of potato, carrot, and sweet potato, wheat grains, corns, and flour dough wrapped with gauze, were buried at 15 cm of soil depth, and collected after 5 and 10 days. The numbers of wireworms attracted by potato pieces, wheat grains and sweet potato pieces after 10 days were 1.8, 1.6, and 1.4/bait, respectively. Therefore, burying potato pieces at 15 cm of soil depth and collected after 10 days could be recommended as a wireworm baiting technique.

• Korean journal of applied entomology
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• v.24 no.4 s.65
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• pp.195-201
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• 1986

This study was conducted to investigate the life history of Compsidia populnea which is major species of the stem-borers on Populus alba{\times}glandulosa$. Peak emergence of the adult of Compsidia populnea L. was around 10th${\sim}$l2nd of May in Chuncheon vicinities, having one generation a year in Korea. There was a preovipositional period of 10.7 days and a ovipositional period of 14.3.days. Mean adult longevity was 11 days for male and 13.8 days for female. Individual eggs were long oval with somewhat narrowed tip at one side and soft, 2.6mm in length, 0.8mm in diameter, and were laid singly under the U-shaped scars which were made by female before oviposition. Total number of scars per female averaged 56.6 ($8{\sim}135$) and eggs were found in 67.9 percent of the total scars. Egg period was $8{\sim}11$ days at $25^{\circ}C$ constant temperature and $7{\sim}14$ days in the field condition. Early young larvae stayed for $2{\sim}3$ weeks under the scars and then boring into the xylem, forming galls at this time. Size of the gall was 1.8cm($1.3{\sim}2.5$) in length, 1.6cm($1.0{\sim}2.2$) in diameter and the length of mine was everage 3.1cm. Fully grown larvae were developed around the early October and overwintered in the mines of galls. Pupation was done around the early of April. Pupal developmental period averaged 11 days($9{\sim}13$ days) at $25^{\circ}C$ constant temperature condition.

• Korean journal of applied entomology
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• v.19 no.1 s.42
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• pp.57-65
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• 1980

The oriental tobacco budmoth, Heliothis assulta Guenee were reared under various temperatures; $20^{\circ}C,\;25^{\circ}C,\;30^{\circ}C$ and the control effects of Thuricide $HP^{(R)}$ were examined. The results obtained were as fellows: 1. The adult longevity of oriental tobacco budmoth was 11.35 days, and 3.00 days for preovipositional period, 4.75 days for ovipositional Period, and 3.50 days for postovipositional period. 2. The total number of eggs laid by a female were 307 at $20^{\circ}C$, 413 at $25^{\circ}C$ and 189 at $30^{\circ}C$. The number of eggs per female per day were 64.05 in average. 3. The average egg Periods were 7.71 days at $20^{\circ}C$, 4.12 days at $25^{\circ}C$ and 3.58 days at $30^{\circ}C$ and the hatchiabilities were $71.25\%,\;78.49\%\;and\;81.05\%$ at the respective incubation temperatures. 4. The larval developmental periods were 43.51 days at $20^{\circ}C$, 21.79 days at $25^{\circ}C$ and 18.05 days at $25^{\circ}C$ and the mortalities were $80.70\%,\;95.93\%$ and $87.01\%$ at the respective temperatures. 5. The pupal developmental periods were 24.22 days at $20^{\circ}C$, 12.36 days at $25^{\circ}C$ and 11.50 days at $30^{\circ}C$ and the mortalities at the respective temperatures were $18.18\%,\;42.11\%\;and\;40.00\%$. 6. The calculated threshold temperatures for the development were $11.61^{\circ}C$ for the eggs, $11.96^{\circ}C$ for the larvae, and $10.06^{\circ}C$ for the pupae. The estimated total effective temperatures were 60.41 day degrees for e eggs, 319.35 day degrees for the larvae, 222.66 day degrees for the pupae, and overall total effective temperatures, however, would be ranged 640-660 day degrees if the reproductive period of the adult was considered. 7. The relationship between the overall developmental periods and the rearing temperature could be Y=-4.272X+155.39 (r=0.9105), where Y; number of days required to complete the life cycle, X; treated temperatures. 8. The control effects of Thuricide $HP^{(R)}$ were $73.43\%$ for spray and $58.22\%$ for bait applications.