• Title/Summary/Keyword: days to emergence

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Difference of Developmental Time, Survival Rate and Sex Ratio of Dichocrocis punctiferalis (Lepidoptera: Pyralidae) on Three Hosts

  • Choi, Kwang Sik;Han, Kyung Sik;Park, Il Kwan;Hong, Jeong Im;Kim, Chul Soo;Chung, Yeong Jin;Shin, Sang Chul
    • Journal of Korean Society of Forest Science
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    • v.95 no.2
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    • pp.174-176
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    • 2006
  • The experiments were conducted by supplying hosts with natural food(chestnut, peach, Quince). The developmental difference of peach pyralid moth, Dichocrocis punctiferalis was examined in the laboratory under three different natural food regime. The periods of egg, larva and pupa were $6.01{\pm}0.07$, $12.23{\pm}0.03$ and $13.32{\pm}0.01$ days on the chestnut fruit, $6.21{\pm}0.01$, $18.69{\pm}0.02$ and $13.38{\pm}0.03$ days on the peach fruit and $7.02{\pm}0.04$, $22.62{\pm}0.04$ and $13.44{\pm}0.14$ days on the quince fruit, respectively. The growth of D. punctiferalis larva was better chestnut fruit than other tested fruits. The rates(%) of hatching, pupation and emergence were 94.0, 57.0 and 63.3 on the chestnut fruit, 89.2, 77.8 and 85.7 on the peach fruit and 79.6, 52.6 and 70.7 on the quince fruit, respectively. The survival rate(%) of D. punctiferalis from hatching to emergence were 31.0 on the chestnut fruit, 4.8 on the peach fruit and 14.3 on the quince fruit, respectively. The sex ratio (female: male) of all pupae obtained on the tested natural food fruits were 52.7 : 47.3. The sex ratio of D. punctiferalis reared on three difference food fruits were no significantly. It can be used a as the basic research for the study of D. punctiferalis.

Studies on the Direct Sowing Culture of Rice in Reclaimed Paddy Field (간척답 벼 직파재배에 관한 연구)

  • Lee, Seok-Su;Shim, Jae-Sung
    • The Journal of Natural Sciences
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    • v.5 no.2
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    • pp.49-62
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    • 1992
  • This study was carried out to investigate the emergence, growth and yield components in rice inassoccation with Several cultivation methods direct sowing flooded paddy field(DSF), direct sowing by airplane(DSA), direct sowing in dry paddy field(DSD), 8days seedling planting(8DS), and 35days seedlingplanting(35DS). Also this study was attempeted to know the effects of calcium peroxide on germinationand early growth of rice under different soil conditions, seeding depth, application of organic matter,indirect sowing flooded paddy field.1. Rate of emergence was 73% in DSF, 70% in DSA, 62% in DSD, respectively, under the different cultivation method of rice in reclaimed paddy field.2. Degree of lodging in relation to cultivation was 5 at both DSF and DSA, 3 at DSD, 2 at both 8DS and 35DS respectively.3. Maximum tiller number was 568 per m2 at DSF and 527 at DSA. Heating was delayed for 4 days at DSF, 8 days at DSD and 2 days at 8DS as comparison with that at 35DS.4. Yield was higher 1% to 3% at DSF than that at DSA and DSD while decreased by 12% as compared with that of seedling planting.5. Total dry weight of seedling was decreased by 57% at 8DS, 60% at DSF 63% at DSD, respectively, under 0.3% of salinity. Ratio of decreasing in dry weight was higher with high salinity.6. The amount of O2 released was recorded highest to 2 to 3days after irrigatition, thereafter remaining constant to 10 days after irrigatition.7. The optimum coating amount of calcium peroxide for germination was a half of rice seed weight with 1 cm sowing depth and one-fold with 2-cm sowing depth when rice straw was not applied. With rice straw applied, on the other hand, the amount of peroxide was one-fold with 1-cm sowing depth. It was found that, under the condition of applied 600kg/10a, of 2-cm soil depth with rice straw calcium peroxide coating had no effect on emergence of rice seedling.8. In reclaimed paddy field, lodging degree was 7 with direct sowing by machine and 9 with direct sowing by hand.9. Yield was increased by 5% by applying rice straw with direct sowing by machine.

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Effects of Weed Amounts Emerged at Different Developmental Stage on Rice Yield (강원지역(江原地域) 논잡초(雜草)의 시기별(時期別) 발생량(發生量)이 벼 수량(收量)에 미치는 영향(影響))

  • Kim, K.S.;An, M.H.;Chang, J.S.;Huh, B.L.;Kim, D.R.
    • Korean Journal of Weed Science
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    • v.10 no.2
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    • pp.83-92
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    • 1990
  • Experiment was conducted to establish the weed control system on the paddy fields by investigating species, period and amount of weeds in Gangwon province. Four locations were selected for these experiments : West plain area, Chunchon(74m above the sea level), mid-mountainous area, Hongchon(300 m), high alpine area, Hoengsong(450m), and east sea area, Myungju(14m). Weed emergence was investigated 6 times from 10 days after transplanting to 60 days with 10 days interval. From the experiments stated above, the results were summarized as follows ; The identity of weed species was small in grass family, but broad-leaf family was numerous. Also the dominant weed species was generally the perenial weeds. The weed emergence was initiated from 10 days after translanting. The amounts of weed counted the most in Chunchon. A large number of weeds were emerged between 30-60 days after transplanting in Chunchon and between 40-60 days after transplanting in Hongchon and Hoengsong. Among agronomic characteristics affected by weed emergence during rice development, plant height was decreased by 2~4cm, panicle number by 1.3~2.9, spikelet by 3.7~7.5, ripening rates 3.3~6.5%, and milled yield by 12~17%, respectively.

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Studies on the Improvement and Management of Hill Pasture (산지초지 개량과 관리에 관한 연구)

  • ;David Leung
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.17 no.4
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    • pp.329-344
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    • 1997
  • To improve germination and growth of forages of hill pasture seeds of several forages were osmotically primed with polyethylene glycol (PEG) under different PEG concentrations, treatment periods, and temperatures. Seeds were coated with several materials, and tested for germination. The best primed or coated seeds in germination tests were surface sow on hilly area. The results obtained are summarized as follows; 1. Osmotic priming with PEG accelerated germination of forages and reduced time taken for germination. 2. Germinability was best when the seeds of Tama ryegrass or orchardgrass were treated for 6-9 days at 30g PEG1100 ml water, red clover or white clover for 3, or 9 days in 20g PEG1100 ml water at $10^{\circ}C$. 3. Priming seeds of Tama ryegrass or orchardgrass in 30% PEG solution for 6 days, and seeds of red clover or white clover in 20% PEG solution for 6 days at $15^{\circ}C$ were most effective in germination, similar to priming at $10^{\circ}C$ . 4. Priming seeds of Tama ryegrass at 15C, and orchardgrass, red clover, or white clover at $10^{\circ}C$ were effective in germination than priming at other temperatures. 5. Osmotic priming with PEG accelerated germination of forages compared to coated seeds in Petri-dishes, while coated seeds germinated more slowly, but showed better emergence and superior growth to those of primed or intact seeds in the field. 6. Priming seeds increased yield slightly, and coating seeds significantly increased its yield on hilly area.

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Change in chemical composition of maturing barley kernels (보리곡립의 성숙중 이화학적 특성변화)

  • Seog, Ho-Moon;Kim, Jong-Sang;Hong, Hee-Do;Kim, Sung-Soo;Kim, Kyung-Tack
    • Applied Biological Chemistry
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    • v.36 no.6
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    • pp.449-455
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    • 1993
  • Some chemical properties were investigated for barley kernels at different growth stages. Crude fat, crude protein, starch, alcohol-insoluble solids(AIS), and ${\beta}-glucan$ increased until $31{\sim}36\;days$ from ear emergence and thereafter remained relatively constant, whereas ash and crude fiber contents were gradually decreased through the whole period of maturation. As barley kernels became mature, their water contents kept decreasing, and the content of milky stage barley kernel at $31{\sim}36th\;days$ from ear emergence ranged from $40{\sim}50%$. Free sugars including glucose, fructose, sucrose, raffinose, maltose, and kestose were identified in the growing kernels. Glucose, sucrose and kestose decreased with maturation while raffinose slightly increased. Barley kernels on the 43rd day from ear emergence contained 0.62% sucrose, 0.46% raffinose, 0.33% kestose, 0.19% glucose, 0.17% fructose, 0.04% maltose. Analysis of minerals for barley kernels at different growth stages showed that the growing kernels contained K, P, Mg, Ca, Na, Fe, Zn, Mn, Cu in decreasing order. Vitamin $B_1$ content tended to increase with kernel growth, showing maximum value of $350\;{\mu}g\;per\;100\;g$ dry weight on 36th day from ear emergence.

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A Study on the Active children's Clothes in the Latter Part of the 18th Century in England -In Relation with Rousseau's Naturalism (18세기 후기 영국에서의 고중적인 어린이 의복 출현에 관한 연구-루소의 자연주의 교육사상과 관련하여-)

  • 이선희;신상옥
    • Journal of the Korean Society of Costume
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    • v.39
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    • pp.139-166
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    • 1998
  • This dissertation is to help understanding about the emergence of active children's clothes in the latter part of the 18th century in England. In previous ages children had not been look-ed upon as children, but as incomplete and in-ferior men and women, the costume of children had not been distinguishable from that of their elders. The early eighteenth-century chil-d could not play in comfort because they dressed like their parents. But in the third quarther of the eighteenth century children became free from their con-comfortable and became active. English chil-dren's clothes was prevailing even in Europe as well. In the background of this liberation, there were many enlightened ideas, such as philosophers of enlightenment, doctors, writers, educators. Among these John Locke and Jean Jacque Rousseau criticized openly about rampant fashion which was distorting the body by corset and hoop. Rousseau was the one who wrote$\boxDr$Emile$\boxUl$and played the most important role to free children from an old fashioned idea, and emphasized to bring up children by the natural process of mental and physical development as human beings are a part of nature. Fashion reflects politic, economic, social, ideology, culture of the days and these factor function to create fashion which shows“Time Spirit”.Children's clothes, like those of their parents, follow the fashion, but with a difference, the form of which varies with the attitude to the child. Thus this dissertation was to study in relation with the background of the times in the latter part of 18th century in England and Rousseau's Naturalism in connection with the emergence of active children's clothes. The result is that diffusion of the idea of freedom and equality, the growth of bourgeoisie, the development of clothing and tex-tile industry have influenced to the emergence of active children's clothes. Also a great deal of middle and high class parents devoted to their children's education and was influenced by Rousseau's Naturalism. Specially the bourgeoisie who made their fortune by their own effort were eager to educate their achievement and business by their children through education. This factor influenced to the children's clothes as well.

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Seedling Growth Pattern and Growth Characteristics in different Seeding Amount in Angelica gigas $N_{AKAI}$. (참당귀묘(當歸苗)의 생육진전(生育進展) 양상(樣相) 및 파종양(播種量)에 따른 묘생육(苗生育) 특성(特性))

  • Yu, Hong-Seob;Kang, Byeung-Hoa;Chang, Yeong-Hee;Kim, Chung-Guk;Kim, Young-Guk;Lee, Seoung-Tack
    • Korean Journal of Medicinal Crop Science
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    • v.3 no.2
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    • pp.84-90
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    • 1995
  • These experiment were conducted to know the seedling growth pattern and to deter­mine the appropriate seeding amount for producing the small and middle sized uniform seedlings of which known to have low bolting in the cultivation of Angelica gigas. Cotyledons of seedling were emerged by 18 days after seeding and the first and the second leaf appeared at 5.0 days and 9.8 days respectively after the anterior leaf emergence. Leaf development from the 3rd to the 6th in order needs about 13 days respectively after the emergence of anterior leaf. Growth of small and middle sized seedling of which required $60{\sim}87days$ were 3.0 to 7.0mm in root head diameter, 6.3 to 10.3cm in root length, 0.4 to 1.3g in fresh root weight per plant with 3.9 to 5.0 leaves. The highest production ratio of small and middle sized seedlings was shown in $15,000seeds/m^2$ of seeding amount as 52.8% respectively.

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Studies on Some Weather Factors in Chon-nam District on Plant Growth and Yield Components of Naked Barley (전남지역의 기상요인이 과맥의 생육 및 수량구성 요소에 미치는 영향)

  • Don-Kil Lee
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.19
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    • pp.100-131
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    • 1975
  • To obtain basic information on the improvement of naked barley production. and to clarify the relation-ships between yield or yield components and some meteorogical factors for yield prediction were the objectives of this study. The basic data used in this study were obtained from the experiments carried out for 16 years from 1958 to 1974 at the Chon-nam Provincial Office of Rural development. The simple correlation coefficients and multiple regression coefficients among the yield or yield components and meteorogical factors were calculated for the study. Days to emergence ranged from 8 to 26 days were reduced under conditions of mean minimum air temperature were high. The early emergence contributed to increasing plant height and number of tillers as well as to earlier maximum tillering and heading date. The plant height before wintering showed positive correlations with the hours of sunshine. On the other hand, plant height measured on march 1st and March 20th showed positive correlation with the amount of precipitation and negative correlation with the hours of sunshine during the wintering or regrowth stage. Kernel weights were affected by the hours of sunshine and rainfall after heading, and kernel weights were less variable when the hours of sunshine were relatively long and rainfalls in May were around 80 to 10mm. It seemed that grain yields were mostly affected by the climatic condition in March. showing the negative correlation between yield and mean air temperature, minimum air temperature during the period. In the other hand, the yield was shown to have positive correlation with hours of sunshine. Some yield prediction equations were obtained from the data of mean air temperature, mean minimum temperature and accumulated air temperature in March. Yield prediction was also possible by using multiple regression equations, which were derived from yield data and the number of spikes and plant height as observed at May 20th.

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Effect of Temperature on the Development of Anagrus incarnatus Haliday (Hymenoptera : Mymaridae) (Anagrus incarnatus Haliay의 발육에 미치는 온도의 효과)

  • 여윤수;장영덕;최귀문
    • Korean journal of applied entomology
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    • v.29 no.4
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    • pp.217-221
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    • 1990
  • Some biological phenomena of Anagrus incarnatus Haliday, an egg parasitoid of planthopper, were studied under three different constant temperatures. Duration from egg to adult emergence of the parasitoid from the BPH eggs were 21.5, 13.6 and 10.6 days under $20^{\circ}C$, $25^{\circ}C$ and $30^{\circ}C$, respectively. Rate of the development was highly correlated with temperature. The critical temperature was estimated as $10.0^{\circ}C$ and the effective degree days was 210.3 day-degree. Durations for the development of A. incarnatus under 25$\pm$$1^{\circ}C$ (16L : 8D) were 12.4, 12.5 and 12.1 days from eggs of N. lugens, S. furcifera and L. striatellus, respectively. Duration of the development of A. incarnatus from 1, 3, 5, 7 days old BPH eggs were 12.5, 12.1, 12.9 days, respectively. The average longevity of adult was 5.3 days under 25$\pm$$1^{\circ}C$. Number of the ovarian and practically oviposited eggs were 34.8$\pm$28 and 28.3$\pm$0., respectively. Female A. incarnatus laid most of the eggs within few days after the emergence ; over 60% within 24 hours, nearly 90% upto the 2nd day, and nearly 100% upto the 3rd day.

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Biological Characteristics of Sclerodermus harmandi (Hymenoptera: Bethylidae) Parasitized on Cerambycid (하늘소류에 기생하는 개미침벌(Sclerodermus harmandi)의 생물적 특성)

  • Hong, Jung-Im;Koh, Sang-Hyun;Chung, Yeong-Jin;Shin, Sang-Chul;Kim, Gil-Hah;Choi, Kwang-Sik
    • Korean journal of applied entomology
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    • v.47 no.2
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    • pp.133-139
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    • 2008
  • This study was performed to investigate the immature development period, fecundity, emergence rate and sex ratio of Sclerodermus harmandi against different host insects, Monochamus alternatus, M. saltuarius and Psacothea hilaris. Full grown larvae and pupae of host insects were provided with foods. The mean larval period of S. harmandi female was $29.2{\pm}0.93\;and\;25.1{\pm}0.47$ days in larvae and pupae of M. alternatus, $27.1{\pm}0.41\;and\;26.0{\pm}0.69$ days in M. saltuarius, and $26.3{\pm}0.38\;and\;31.2{\pm}0.24$ days in P. hilaris, respectively. S. hilaris adults were emerged at $12.9{\pm}0.2$ days in female and $11.9{\pm}0.2$ days in male after pupation when hosted M. alternatus pupa. Development period in male showed shorter one day than in female. Success rate of oviposition against different hosts was higher as 98.6 and 97.5% on full grown larva and pupa of M saltuarius. Emergence rate was higher as 90.1 and 87.3% on M. saltuarius larvae and pupae. Sex ratio of emerged S. harmandi adults was approximately 10:1 (Female : Male), females showed higher emergence rate than males. The period until first oviposition after emergence in S. harmandi female was the shortest in $4.6{\pm}0.1$ days on M. saltuarius pupa. When three females of S. harmandi were inoculated on M. saltuarius larva, the number of laid eggs was the highest $62.7{\pm}2.5$ per female.