• Journal of Embryo Transfer
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• v.3 no.1
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• pp.43-47
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• 1988

공란우 89두와 수라우 94두를 사용하여 호르몬 투여에 대한 난소반응, glycerol의 평형과 제거방법에 따른 융해란자의 형태적 정상성과 동결 융해란의 이식후 임신율과 쌍태유기율을 조사하였다. 1. 호르몬처리에 대한 난소반응 :1) 과배란 처리후 배란된 난자수는 A.B.C군에서 각각 8.3, 7.8, 9.5개로서 C군이 전체 평균의 8.3개보다 증가되었다. 2) 난자의 회수율은 42.1%, 두당회수된 난자수는 3.5개였으며, 회수란자중 정상발육한 상실배와 배반포기의 난자는 63.3%, 36.7%(114/311)가 형태적 이상란자로 확인되었다. 2. 수정란의 동결 융해후 형태적 정상성 :1) 동결융해후 회수된 난자중 정상 난자의 비율은 60.4%였으며, 배반포(62.3%)가 상실배(58.3) 보다 우수하였다. 2) 1단계 glycerol의 제거시에는 동결전 glycerol의 평형을 3단계로 실시한 군(C.G)이 1단계 평형군 (A.E)보다 우수하였다. 3. 동결융해란의 이식후 쌍태유기 :1) 수정란의 이식후 임신율은 단태(대조)구에서 30.0%, 쌍태유기군인 A(AI+단태), B(편각쌍태) 및 C(쌍각쌍태)구에서 각각 55.6, 44.4, 37.5%로서 대조구보다 증가되었다. 2) 쌍태유기에 공용된 26두의 수란우에 착상된 수정란수는 17(65.4%)개로서 딘태구(30.0%) 보다 배가되었다.

• Korean journal of applied entomology
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• v.44 no.4 s.141
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• pp.277-282
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• 2005

This study was conducted to investigate morphological characteristics and effects of temperature on the development of Piezodorus hybneri on soybean. The unibanded stink bug, Piezodorus hybneri, is a serious insect pest in soybean fields giving damage to seeds in pod and leaves of soybean lowering both quality and yield. Eggs were spherical and laid in two raws on the leaves and pods of soybean plants. Body lengths of females and males were 9.8 mm and 8.7 mm, respectively. Egg hatch rates were better in higher temperature within the range of examined temperatures, which ranged in $81.2{sim}93.2%$. The development periods of eggs at the temperatures of 20, 25, 30 and $35^{\circ}C$ were 10.7, 5.0, 4.0, and 3.0 days, respectively. Mean developmental periods of 1st, 2nd, 3rd, 4th and 5th nymphs at $25^{\circ}C$ were 3.2, 3.4, 3.4, 3.3 and 5.9 days, respectively. Development threshold and effective accumulative temperature were $13.3^{\circ}C$ and 65.5 DD (day degree) for egg stage, $9.9^{\circ}C$ and 322.8 DD for nymph stage, $10.7^{\circ}C$ and 386.4 DD from egg to adult, respectively. Oviposition began from 10 days after emergence at $25^{\circ}C$, and the longevity of female and male were 52.5 and 38.2 days, respectively. Total number of eggs and egg masses laid by a female at $25^{\circ}C$ were 496 and 21.3, respectively, The longevity of adult female was shortened with increasing temperature, whereas the total numbers of eggs laid by a female were decreased.

• Korean journal of applied entomology
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• v.60 no.4
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• pp.403-415
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• 2021

Seasonal development of Parthenolecanium corni was observed from 4 Jun. 2019 (nymph) - 25 Jun. 2020 (1^st Gen. nymph) in blueberry shrub in Sacheon city, Gyeongsangnam-do. To investigate their development, more than 5 twigs sprouted in 2018 were taken from the farm nearly weekly basis. The development of each scale were examined under the stereomicroscope and chemical control was conducted in the blueberry shrub with available three insecticides. The results on the development period and Centigrade Degree-Days accumulation (DDC) obtained are as follows: egg-laying period (peak): 12 -26 May 2020 (24 May)(DDC, 110.0-188.5 (173.6)); egg-hatching period (peak): 9 - 23 June 2020 (19 June)(DDC, 325.2-480.8(435.6); egg period: 26 days; nymph movement from overwintered adult to new leaves 16-25 June 2020 (DDC, 410,5-500.4); nymph movement from leaf to twig (peak) to become adult: 4-18 Feb. 2020 (8 Feb.). Eggs no. /adult (range): 956.8 ± 73.4 (13 - 3497). Size (mm) of egg, 0.29 ± 0.020(L), 0.15 ± 0.013(W); of egg-hatched nymph, 0.35 ± 0.018(L), 0.18 ± 0.007(W), 0.09 ± 0.007(eye distance); and of adult, 4.30 ± 0.893(L), 2.64 ± 0.520(W). The egg-hatched nymphs from the overwintered adult moved to the backside leaf of new shoot in which they found about 95% until leaf is falling by early February in next year. They overwintered as 2^nd instar and occurred univoltine. For the control of the 1^st instar crawler, three insecticides treated on 16 and 30 July at the registered dose for Ceroplastes japonicus. Acetamiprid 8WP showed 96.9% mortality at 21 days after 1^st treatment.

• Korean journal of applied entomology
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• v.47 no.3
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• pp.227-235
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• 2008

Development of T. urticae was studied on the leaves of eggplant grown in hydroponics with silica contents of 0 mM, 1.7 mM, and 5.1 mM. As the levels of sllica increased, those of N, P, K, Ca, and Mg decreased and those of Si increased. While contents of calory, crude protein, carbohydrates, and vitamin C decreased, those of ash, fiber, and sugar increased. Biomass and content of cholorophyll decreased as the level of silica increased while leaves became thicker. Laboratory leaf disc tests provided with various silica levels revealed that feeding preference of T. urticae was the highest at 0 mM and the lowest at 1.7 mM. The oviposition preference decreased as the levels of silica increased, on the lower leaf appeared to hinder the feeding and the oviposition of T. urticae. The development slowed down both in female and male. Adult life span of female shortend as the silica level increased and that of male was the longest as 5.7 days at 0mM and the shortest at 1.7 mM. Oviposition period also shortened as the silica content increased. The number of eggs laid was the most as 86.3 at 1.7 mM while average oviposition per day was the least as 77 at 0 mM. No differences in hatchability was detected whereas the ratio of sex was the highest as 0.71 in favor of female at 0mM. $R_o$ and T decreased as the levels of silica increased. Rm and $\lambda$ was the lowest at 5.1 mM while Dt was the longest as 1.8271 at 5.1 mM and the shortest as 1.6991 days at 1.7 mM. Silica content in eggplant turned to affect the development of T. urticae, however, it deterred T. urticae from feeding and oviposition and the rate of increase tended to decrease due to lesser nutrients in the eggplant leaf.

• Korean journal of applied entomology
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• v.46 no.1 s.145
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• pp.51-56
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• 2007

The two species of rice bugs causing pecky rice, Cletus punctiger and Cletus schmidti are often observed coexisting in the rice fields of nearby fallow land. Direct feeding damage to rice by C. punctiger and C. schmidti can lead to a reduction in grain quality and quantity. These studies were carried out to investigate the development of C. punctiger and C. schmidti at various constant temperatures ranging from 20 to $30^{\circ}C$, 65% RH, and a photoperiod of 16L:8D. Egg hatchability of C. punctiger/C. schmidti at the temperatures of 20, 25 and $30^{\circ}C$ were 80.6/88.0, 91.7/96.3, 96.4/96.2%, respectively. The development periods of eggs of C. punctiger/C. schmidti at the temperatures of 20, 25, and $30^{\circ}C$ were 16.4/18.4, 9.4/10.2 and 6.4/7.3 days, respectively. Mean developmental periods of 1 st, 2nd, 3rd, 4th and 5th nymphs of C. punctiger/c. schmidti at $30^{\circ}C$ were 2.1/2.0, 3.5/4.0, 3.3/5.6, 3.2/4.8 and 5.8/6.9 days, respectively. Oviposition began 8.1 days after emergence at $25^{\circ}C$, and the longevity of female and male were 120.0 and 117.3 days, respectively. Total number of eggs through the life of female were 245.5 laying 2.2 eggs a day in average at $25^{\circ}C$. The development periods of egg and nymphs of C. punctiger were relatively shorter than those of C. schmidti. Availability of male had affected the egg hatchability greatly that laid at 30th day after 60 days period of oviposition in the presence of adult male of C. punctiger. The fertile eggs laid by the female together with male was 92.1% but those without male was only 9.6%.

• Korean journal of applied entomology
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• v.37 no.2
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• pp.171-178
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• 1998

This study was conducted to investigate the effect of temperature on the development of amushroom-infesting sciarid fly, Bradysia sp. (Diptera: Sciaridae). Egg period was 12.1, 7.0, 4.4, 3.4, and3.2 days, larval period was 38.3, 26.5, 13.4, 13.2, 12.7 days and pupal period was 10.4, 7.1, 4.4, 3.3, 3.2days, and total development period from egg to adult emergence was 60.8,40.6, 22.2, 19.9, and 19.1 daysat 10, 15, 20,25, 28"C, respectively. Development threshold temperature (DT) and effective accumulativetemperatures (ET) were 3.8"C, 74.8DD in eggs, 1.2"C, 321.8DD in larva, and 3.1$^{\circ}$C, 76.5DD in pupa,respectively. The number of eggs laid per female was 107.9, 129.7, 131.8, 86.9, and 82.7 at respectivetemperatures. Preoviposition period was 6.6, 4.4, 2.2, 1.3, 1.8 days, oviposition period 1.5, 1.5, 1.1, 1.1,1.1 days, postoviposition period 2.0, 1.1, 0.9, 0.6, and 0.3 days at th'e temperature of 10, 15, 20, 25 and 28"C, respectively. The longevity of male and female at the temperature was 13.3, 7.8, 5.9,4.1, 3.4 days and10.4, 7.0, 4.2, 3.0, 3.3days, respectively. The optimum temperature for hatchability was estimated to the20$^{\circ}$C and adult emergence was highest at 20$^{\circ}$C. Pupation rate was 50.7, 68.4, 84.3, 86.5, 45.4% at 10, 15,20, 25, and 28"C, respectively. at 10, 15,20, 25, and 28"C, respectively.tively.

• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.526-532
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• 2017

Development, survival, and reproduction of brown planthopper (BPH) Nilaparvata lugens $St{\aa}l$ (Hemiptera: Delphacidae), were studied in laboratory at $25{\pm}2^{\circ}C$, $65{\pm}5%$ RH and a 16L : 8D hours photoperiodism on five rice cultivars of: Dongjin 1ho, Chungchungbyeo, Jangseongbyeo, Chinnongbyeo and Jungmo 1045. BPH nymphs successfully survived on all rice cultivars, although survival rate was lowest on Jangseongbyeo (36.0%). Developmental time of immature stages ranged from $11.7{\pm}0.59d$ on Jungmo 1045 to $12.8{\pm}0.59d$ on Chinnongbyeo. Reproductive period and female longevity were longest on Dongjin 1ho, Chinnongbyeo and Jungmo 1045 while highest fecundity of N. lugens being observed on these three rice cultivars. Highest and lowest net reproductive rates were calculated on rice cultivars, Jungmo 1045 and Jangseongbyeo, respectively. Mean generation time was the longest on rice cultivar Dongjin 1ho. Respective descending order of intrinsic rates of population increase were on Jungmo 1045, Chinnongbyeo, Dongjin 1ho, Chungchungbyeo and Jangseongbyeo. These population parameters showed that N. lugens can successfully survive and reproduce on Chinnongbyeo and Jungmo 1045.

• Korean Journal of Poultry Science
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• v.30 no.2
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• pp.91-94
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• 2003

Artificial insemination of cryopreserved semen is not practiced in broiler breeder industry although its benefit has been recognized for years. Thus, the present study explored the possibility of artificial insemination with cryopreserved semen in Ross broiler breeders. Sixty Ross female broiler breeders were artificially inseminated either with fresh or with cryopreserved semen pooled from five male Ross broiler breeders. On.e hundred eighty eggs were collected from each semen treatment and hatched. Fertility and hatchability of fertilized eggs collected from hens artificially inseminated with cryopreserved semen were 68.0 and 47.1％, respectively, compared to 88.3 and 87.2％ with fresh semen. Both unfertilized eggs and dead embryos during hatch were significantly (P<0.05) higher in the cryopreserved semen­treated group by approximately 2.7­ and 3.2­fold than the fresh semen­treated counterparts. the moderately low fertility and markedly low hatchability of fertilized eggs obtained from cryopreserved semen observed in this study may be of practical interests in broiler breeder industry and deserves further study.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.3
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• pp.232-241
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• 1984

A series of experiments were carried out to know the effects of pollen stage, cold shock temperature and duration, and media for callus and green plant induction in rice anther culture. The results indicated that: (a) uninucleate stage of pollen was the most suitable stage for effective callus induction, (b) cold shock temperature of 8$^{\circ}C$ and 12$^{\circ}C$ was appeared to be proper temperature for callus induction, (c) callus induction rate was increased in the eight to 12 days long cold storage, (d) the medium N6 was better than that of N6D for callus induction, (e) green plant induction was better in both 4$^{\circ}C$ and 8$^{\circ}C$ than that of 12$^{\circ}C$ cold shock, (f) green plant frequency was higher in eight to 12 days long cold storage and (g) green plant frequency was doubled in the MS medium when compared with N6 medium.

• Korean journal of applied entomology
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• v.42 no.3
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• pp.203-209
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• 2003

Biological characteristics of the almond moth, Cadra cautella, of which eggs will be substitute diets for Orius spp. and Trichogramma spp., were investigated and a mass-rearing system for the moth was developed. At 25$^{\circ}C$, egg, larval, and pupal period was 4.2, 29.8 and 8.3 days, respectively, and adult longevity was 5.8 days for female and 4.8 days for male. Total number of eggs at 20, 25 and 30$^{\circ}C$ was 128.9,207.9 and 139.9, respectively. The moth could be successfully reared with all food substrates tested, of which rice bran (50%)+chick feed (50%) assumed to be proper for massrearing in view of cost. Eggs could be stocked at 9 C for 7 days, representing 82% hatchability. In the rearing cage (16${\times}$24${\times}$9cm) used, 1,000 eggs was better for initial level of inoculation, showing relatively high emergence rate and adult weight. Mass-rearing procedures were explained in detail.