• Korean Journal of Medicinal Crop Science
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• v.6 no.4
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• pp.328-332
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• 1998

This study was carried out to investigate the occurrence and ecological characteristics of Ostrinia furnacalis(Guenee) in Yonchon, northern part of Kyonggi province, where it is main production region of adlay in Korea. The Asian corn borer in adlay field had three generations a year. The first stage of adult activity was greatest from middle May to late June, the second from late July to middle August and the third from late August to middle September. The egg period was $3{\sim}4$ days. The longevity of adult was $7{\sim}11$ days. The days of each development stage from egg to adult were $51{\sim}61$, $33{\sim}42$ and $29{\sim}37$ days in 1st, 2nd and 3rd generations, respectively. The overwintering stage of Asian corn borer was the last instar larvae and it overwintered in the adlay stubbles.

• Korean journal of applied entomology
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• v.25 no.4 s.69
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• pp.201-207
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• 1986

This study was conducted to investigate the host plants in greenhouse, developmental periods at different temperatures and distribution patterns on cucumber of the greenhouse whitefly, Trialeurodes vaporariorum(TV) in $1984{\sim}1985$. Host plants of 39 species belonging 27 families only in the greenhouse were recorded in 1984. Longevity of adult was 26.8 days and number of eggs per female was 305 eggs at $25^{\circ}C$. The eggs, larval and pupal periods were 8.2, 8.3, 7.5 days respectively at $25^{\circ}C$. The threshold temperature of development from egg to larva was $8.8^{\circ}C$. Survival rates from eggs to adults at $22^{\circ}C,\;25^{\circ}C,\;30^{\circ}C$ were 70.3%, 58.0% and 66.4%, respectively. Adults and eggs were found only on the apical leaves of cucumber plants within 40 days after transplanting. On the other hand, larva distributed on the middle leaves and pupa on the lower leaves.

• Korean journal of applied entomology
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• v.36 no.1
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• pp.111-117
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• 1997

Occurrence status of Tetranychus viennensis Zacher was investigated in Kyonghuk province. Its ecological studies were carried out and chemical control efficacy against females and eggs was examined. And the results ohtained are as follows. T. viennensis occurred from mid April through mid November with the peak time in June on cherry tree. Population level of T. viennensis was varied from 0 to 160 individuals per 100 peach leaves in different peach orchards, and its occurrence rate was 35% out of 20 ochards. However no T. viennensis was observed from 25 apple orchards in 5 districts of Kyongbuk province. Overwintering stage of T. viennensis females appeared in mid October, and most of them moved into under the rough hark in early November. The overwintered adult females moved out from the rough bark to leaves in early April. Mortality during overwintering was about 55%. Under four constant temperatures of 16, 19, 22, 25$^{\circ}$C. egg periods were 14. 3, 9.2, 6.8, and 4.0 days ; larva -nymph periods were 20.2, 13.9, 8.7, and 6.6 days. Female longevity was 67. 7, 60.7, 46.4, and 34.0 days : mean tota: fecundities per female were 21.2, 44.3, 54.4, and 64.7 eggs. Some acaricides, azocyclotin, pyridaben, propargite, tehufenpyrad and fenpyroximate were highly effective against females, while hexythiazox and clofentezine showed very low control effect from 3.6 to 14.4%. Whereas, all of 7 acaricides tested highly effective against the eggs.

• Korean journal of applied entomology
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• v.34 no.4
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• pp.300-307
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• 1995

This study was carried out to investigate the life cycle of Cephonodes hylas (Linne), that is damaging to Gardenia jasminoides Ellis in the seedbed at Namhae during 1984 and 1985. Results are summarized as follows. The eggs were laid in mass on the leaf surface of the host plants. The oviposition period lasts for 26 days after late-May. The average number of eggs and average hatching rate were 20.36 and 97.61% , respectively. It takes 14-16 days until hatching. The egg shape was oval which its size was 1.01 mm in diameter and 1.48 mm in length. The body length of each larval instar from the 1st to the 5th were $3.52\pm$1.01, $6.46\pm$0.45, $13.19\pm$4.27, $24.08\pm$2.22 and $43.71\pm$5.62 mm, respectively. The average weight of each larval instar were $13.34\pm$2.41, $29.83\pm$6.88, $76.64\pm$31.31, $292.09\pm$107.70 and 2,$144.84\pm$760.70 mm, respectively. The larval period was observed from July to October, and total duration of larval stage was 116 days in which duration of each larval instar from the 1st to the 5th were 12, 36, 32, 16 and 20 days, respectively. During larval stage, a larvae feed on 17~18 seedlings. The 5th instar larvae built its place in soil for overwinter and became pupa. The body length of pupa was 33.6 mm and average weight was 2,032 mg Adult was emerged from overwintened pupa from mid through late-May in the followings year. The sex ratio of female was 42.82% and the color ratio of brown was 89.93%.

• Korean journal of applied entomology
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• v.41 no.2
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• pp.123-128
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• 2002

This study was carried out to test the effects of temperatures between 2$0^{\circ}C$ and 3$0^{\circ}C$ on the reproduction and development of the rice water weevil, Lissorhoptrus oryzophilus. Preoviposition periods were much longer (17.2 to 51.0 days) in the overwintering adult females collected in March than those collected in May, regardless of temperature. Oviposition periods, however, were longer (16.9 to 22.0 days) in the adult females collected in May than those collected in March at the same temperatures. The longer oviposition period observed in the females collected in May were directly associated with higher fecundity. Egg periods were shortened from as temperature increased, but the hatching rate was highest (100%) at 27$^{\circ}C$. The developmental periods from egg to adult were shortened as temperature increased : from 77.9 days at 2$0^{\circ}C$ to 38.3 days at 3$0^{\circ}C$. The developmental zero point temperature (T) and the total effect temperature (K) for egg were 16.3$^{\circ}C$ and 62.1 dgree days, respectively. The T and K from egg to adult emergence were 13.9$^{\circ}C$ and 577.6 dgree days, respectively. The adult females of the first generation did not oviposit at 2$0^{\circ}C$, but did at $25^{\circ}C$ and 3$0^{\circ}C$. The intrinsic rate of natural increase (r$_{m}$) increased as temperature augmented. Net reproductive rate (Ro) per generation was highest (75.3) at $25^{\circ}C$.>.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.4 no.1
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• pp.25-29
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• 1968

The effect of differences in grain size on the initial growth of seedlings was studied in rice with two leading varieties of Jaekun and Nongkwang. The grains were classified into three classes of large, medium and small size by their specific gravity. The results observed at seedling stage are summarized as follows. 1. Higher percentage of seeds with larger size was observed to be normally developed into sound seedlings comparing with those with small seeds. This suggests the more effective maintainance of seedings. 2. Seedlings from larger seeds also showed higher values in the number of roots, leaves and tillerings where no varietal difference was observed. 3. Varietal speciality led to the lorger coleoptile of Nongkwang variety, with rather longer plant, than that of Jaekun, while higher value in coleoptile length was observed at the seedlings from larger seeds. 4. Thus larger seeds and the Aariety Nongkwang yielded heavier dry matter of upper part. These trends appeared more clearly at the late seedling stage. 5. There was constant decrease in the dry matter weight per unit coleoptile length until the seedling-selfsupportingstage while after this stage abrupt increase was observed. Seedlings from larger seeds showed higher value in the dry matter weight per unit coleoptile until this stage, thought the differences became insignificant after this stage. And no varietal difference was found.

• Korean journal of applied entomology
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• v.23 no.4 s.61
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• pp.233-236
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• 1984

Studies were conducted to investigate the effect of Carbofuran 3G on the density variation of rice pests and their natural enemies in case the insecticide was treated two times as compared with usual trials in paddy field. Even the two times application of Carbofuran 3G in the nursery boxes of machine transplanting and paddy water trials obtain same results to pests, small brown planthopper (Laodelphax striatllus), green rice leafhopper (Nephotettix cincticeps), brown planthorper (Nilaparvata lugens), white back planthopper (Sogotella furcifera), rice stem bore (Chilo suppressalis), rice stem maggot (Chlorops oryzae), rice thrips (cloethrips oryzae) as compared with usual trials. The density of natural enemies, spiders and egg parasite, Anagrus sp. of planthoppers in the two times application part of Carbofuran 3G increased 2.4 fold as compared with usual trials.

• Korean journal of applied entomology
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• v.36 no.1
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• pp.48-54
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• 1997

This study was conducted to determine the effect of temperatures and food sources on the egg and larval developmentof the tobacco cutworm, Spodoptera litura Fabricius. The hatchability of egg masses of S. liturawas 100% on the leaf of soybean, perilla and sweet potato in any given temperature regimes, while the hatchabilitywas only 65-8796 when reared on the pulp paper and decreased as temperature increased. Egg durationwas not significantly different among different food sources within each temperature. However, egg duration at32$^{\circ}$C was shorter than that at 24$^{\circ}$C and 28$^{\circ}$C. During the early larval development, at 28$^{\circ}$C and 32$^{\circ}$C the larvafed on sweet potato leaf was heavier than those fed on soybean and perilla leaves and the opposite case wastrue during mid-larval development stage. However, larval weight at 24$^{\circ}$C was heavier on sweet potato leafthan that on soybean and perilla leaves until 12 days after hatching. This result was probably due to relativelyslower developmental rate at 24$^{\circ}$C compared to 28$^{\circ}$C and 32$^{\circ}$C. The mean larval mortality was 68.896, 44.5%and 33.8% at 24$^{\circ}$C. 28$^{\circ}$C and 32"C, respectively. The lowest mortality was observed on soybena leaf and followedby perilla and sweet potato leaves, and artificial diet regardless of temperature conditions. The durationwas the shortest when they fed on soybean leaf, and followed by perilla and sweet potato leaves and artificialdiet. Larval durations were 23.6-30.4 days at 24$^{\circ}$C. 18.6-22.3 days at 28$^{\circ}$C and 14.5-18.0 days at 32$^{\circ}$C. Thethreshold temperatures of egg and larva of S. litura were about 6.l"C and 10.9"C, respectively.t 6.l"C and 10.9"C, respectively.pectively.

• Korean journal of applied entomology
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• v.36 no.4
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• pp.311-316
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• 1997

This study was conducted to evaluate the effect of temperatures on the egg and nymphal development andadult longevity of green mirid bug, Cvrtorhinus lividipennis Reuter. In addition, predation on eggs of brownplanthopper, Nilupurvurcz lugens ~t:l and small brown planthopper, L~orlelphux .striatellus Fallen by C.lividipennis were studied at different temperatures. Hatchability of C. lividipennis was about 96% at 23"C,88% at 26"C, 75% at 29$^{\circ}$C and 64% at 32$^{\circ}$C. Egg duration of C. lividipmnis was 1 1.0 days at 23"C, 10.0 at26"C, 6.7 days at 29$^{\circ}$C and 5.6 days at 32$^{\circ}$C. Nymphal duration of C. 1i1~idiperzni.ws as 13.7 days at 23"C,12.7 days at 26$^{\circ}$C. 10.2 days at 29$^{\circ}$C and 9.1 days at 32$^{\circ}$C regardless of food sources. Nymphaldevelopment was the shortest at 4th instar and the longest at 1st instar irrespective of temperatures and foodsources. Adult longevity of C. livirlipennis was was about 22.0 to 23.5 days at 23$^{\circ}$C. 19.0 to 20.0 days at26"C, 16.0 to 17.0 days at 2Y0C, and 1 1.0 to 12.0 days at 32$^{\circ}$C. There was no significant difference in adultlongevities on food sources. Number of eggs comsumed by adult C. lividipennis were about 56 to 61 and 56to 57,56 to 60 and 47 to 49,43 to 46 and 40 to 42, and 28 to 30 and 26 to 27 at 23'C. 20$^{\circ}$C. 29$^{\circ}$C and 32"C,respectively. Egg consumption by adult C. lividiprrznis was slightly higher at female and on N. lugens eggthan at male and on L. striatellus egg. Dail 2.0 to 3.0 eggs were consumed by adult C. lividipc,nni.s.ail 2.0 to 3.0 eggs were consumed by adult C. lividipc,nni.s.

• Journal of Life Science
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• v.18 no.12
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• pp.1728-1732
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• 2008

This study was performed to investigate the bionomical characteristics of Luciola lateralis in Korea. Imago's longevity of female was $17.5{\pm}0.7$ and male was $20.6{\pm}1.0$ days at $23^{\circ}C$, R.H. 80%, and significant difference was not occurred in breeding density. Pre-oviposition period was a pair $2.8{\pm}1.5$, two pairs $2.5{\pm}1.5$, three pairs $1.7{\pm}0.7$, four pairs $1.3{\pm}0.5$ days and pre-oviposition period was shorten in higher breeding density. The mean of laying eggs was $248.9{\pm}80.7$, was not related breeding density. Daily oviposition rate was 1st day 20.8%, 2nd 17.3%, 3rd 14.3%, 4th 12.7%, 5th 7.0%, the rate was highest in 1st day and gradually reduced. Egg period was $21.8{\pm}0.7$ days and hatchability was $95.5{\pm}4.8%$. Larval instar was identified the 9th instar, the evidence was able to its skin and marking pattern. Larval period of each instar was 1st $1.0{\pm}0.1$, 2nd $3.3{\pm}0.2$, 3rd $10.2{\pm}1.0$, 4th $6.8{\pm}0.5$, 5th $6.9{\pm}2.0$, 6th $15.4{\pm}4.1$, 7th $18.3{\pm}5.9$, 8th $25.8{\pm}8.7$, 9th $31.2{\pm}13.2$ days. Matured 9th larva was made of cocoon during $2.8{\pm}0.8$ days and pre-pupal, pupal period was $4.6{\pm}0.9$, $5.6{\pm}0.7$ days. Imago was made hard hind wing during $3.8{\pm}0.4$ days in cocoon and come out.