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Studies on Inheritance and Ecological Variation of the Culm Length and Its Related Characters in Short-Statured Rice Varieties (수도단간품종의 간장 및 관련형질의 유전과 생태적 변이에 관한 연구)

  • Sung-Ho Bea
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.13
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    • pp.1-40
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    • 1973
  • These studies were aimed at clarification of genetic and ecological variation in culm length, panicle length and plant height of the $\textrm{F}_2$ plants in some selected crosses made between semi-dwarf rice varieties and tall Japonica ones. One Indica semi-dwarf, Taichung Native 1, one Indica $\times$ Japonica hybrid, IE51 and one Japonica semi-dwarf, Tankanbaekmang were used as short-gene donors while two of medium maturity varieties, Jinheung and Kwanok and one late veriety, Palkweng were used as the corresponding counterpart of respective dwarf varieties in a series of crosses. Five different crosses, Kwanok $\times$ Tankanbaekmang, Palkweng $\times$ Tankanbaekmang, Jinheung $\times$ T(N)1, Kwanok $\times$ T(N)1 and Kwanok $\times$ IE51, were made among the above six varieties. The $\textrm{F}_2$ plants of these crosses together with the concerned parental varieties were grown under several different conditions including three levels of each nitrogen and planting space, three planting seasons and three locations in 1968, to investigate variation in length of culm and panicle, and plant height. On the other hand, the F$_3$ progenies which were derived from the shortest 10 percent of the plants of three $\textrm{F}_2$ populations, Kwanok $\times$ T(N)1, Jinheung $\times$ T(N) 1 and Kwanok $\times$ IE51 grown in the previous year, were compared each other on the basis of selection efficiency in culm length. The experimental results could be summarized as follows; 1. Genetic behavior A. It was revealed that Tankanbaekmang, one of Japonica dwarf has a simple recessive gene responsible for short culm expression, showing a typical segregation ratio of three tall to one short culm plants in $\textrm{F}_2$ generation of the crosses either with Kwanok or Palkweng. B. In the both combinations, segregation pattern of the panicle length was exactly same as that of culm length. It seems that the same gene controls both culm length and panicle length. C. No difference between segregation of culm length and plant height in the above crosses was observed. D. T(N)1, one of Indica semi-dwarf did not show such a simple genetic behavior as detected from the crosses with Tankanbaekmang in segregation of culm length but formed a continuous and normal distribution curve. Therefore, some nonallelic genic actions might be involved in expression of culm length of the counterpart varieties of T(N)1. In particular, a transgressive segregation appeared toward the direction of longer culm length in case of Jinheung $\times$ T(N)1. The genetic behavior of panicle length and plant height generally coincided with that of culm length in all the cases. E. IE51 demonstrated exactly the same genetic behavior as that of T(N)1 when this variety was crossed with Kwanok. It was clearly clarified that the simple recessive gene controlling dwarfism from T(N)1 was well incorporated into this variety. 2. Ecological variation A. In general, there was a decreasing tendency in culm length and plant height of rice plant as seeding delayed while it was not so noticeable in panicle length. The decreasing magnitude varied from variety to variety and from cross to cross. Genetic behavior of the culm length and related characters of these materials was not disturbed by the variation of seeding season, nitrogen level, planting space and experimental location. E. The elongation mode of the upper three internodes was very similar to the segregation mode of culm length, panicle length and plant height in $\textrm{F}_2$ populations of . all the crosses investigated in this study. Accordingly, this result confirmed that the roles of the upper three internodes are very important in manifesting plant stature in rice. C. The effect of nitrogen on culm length and the related other two characters seemed to be meager. However, it was true to show an increasing tendency of those characters as nitrogen level got increased from 4 kg to 12kg per l0a, with different magnitude depending upon variety or cross. D. Also, the effect of planting space on culm length, panicle length and plant height was relatively small in all the cases. Those characters varied again depending upon variety or cross. However, a general increasing tendency was detected in manifestation of those traits under denser planting space condition. E. All the parental varieties produced shorter culm, panicle and plant height when they were grown at the lower latitude locations. It might be attributed to the fact that their reproductive growth accelerated with increased temperature prevailing at the lower latitude locations such as Iri and Mi1yang. On the countrary, $\textrm{F}_2$ population reacted differently to the different locations from the parental varieties. All the $\textrm{F}_2$ plants produced the longest culm, panicle and plant at Milyang. 3. Selection efficiency A. The heritability of culm length in Kwanok $\times$ T(N)1, Kwanok $\times$ IE51 and Jinheung$\times$T(N)1 was 92 percent, 74 percent and 55 percent, respectively. B. The actual genetic advance for culm length obtained from the progeny lines of the selected plants(10 precent) from the $\textrm{F}_2$ generation, was comparable to the expected advance calculated from the original $\textrm{F}_2$ populations. As compared with the $\textrm{F}_2$ population, the $\textrm{F}_3$ plants of Kwanok $\times$ T(N)l shortened on the average by 20.8cm, those of Kwanok $\times$ IE51 did 8.7cm and those of Jinheung$\times$T(N)1 20.0cm, respectively. C. Panicle length of the populations was differently affected from one cross to another by the selection based upon culm length in $\textrm{F}_2$ Kwanok $\times$ T(N)1 did not show any noticeable shortening of its culm length due to the selection pressure. On the other hand, both Kwanok $\times$ IE51 and Jinheung $\times$ T(N)1 showed a considerable shortening of their panicles in case of selection for culm length. Based upon the above results, it could be concluded that the ecological variation in culm length, panicle length and plant height was relatively small and fallen within the range of genetic variation. Considering from the fact that the simple recessive gene governing short height of Tankanbaekmang always accompanied with some undesirable characters such as short panicle and extremely small grain, the short gene of T(N)1 seemed to be more useful as dwarf gene source since it did not carry short gene together with such undesirable traits.

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A Study of Altered IL-6 and TNF-α Expression in Peritoneal Fluid of Patients with Endometriosis (자궁내막증 환자의 복강 액내 IL-6와 TNF-α의 변화 양상에 관한 연구)

  • Kang, Jeong-Bae;Lee, Young-Kyeong
    • Clinical and Experimental Reproductive Medicine
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    • v.33 no.1
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    • pp.45-52
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    • 2006
  • Objective: Our purpose was to investigate the relationship between the levels of IL-6 and tumor necrosis factor-${\alpha}$ in the peritoneal fluid of women with and without endometriosis and infertile women. Methods: This study is prospective and case-control study in University hospital, enrolled thirty-four women with laparoscopic findings of minimal to severe endometriosis, and thirty-seven women with no visual evidence of pelvic endometriosis and with benign gynecologic disease. IL-6 and tumor necrosis factor-${\alpha}$ levels in peritoneal fluid were determined using commercial ELISA. IL-6 and tumor necrosis factor-${\alpha}$ concentrations were compared among women with and without endometriosis, and with infertile and fertile women, and then also compared according the revised American Fertility Society classification. Results: IL-6 and tumor necrosis factor-${\alpha}$ concentrations were higher than in the peritoneal fluid of women with endometriosis than in matched normal controls. Cyclic variations in IL-6 concentrations were seen in peritoneal fluid from patients with endometriosis: the concentrations in the secretory phase were significantly higher than those in the proliferative phase. The concentrations were higher than among of infertile women than in fertile women. A significant correlation between IL-6 and tumor necrosis factor-${\alpha}$ concentrations and endometriosis stage III and IV was noted. Conclusion: Increased levels of IL-6 and tumor necrosis factor-${\alpha}$ in patients with endometriosis in the peritoneal fluid may be relate to the pathogenesis of endometriosis suggesting that partially contribute to the disturbed immune regulation observed in patients with endometriosis.

The Changes of System Design Premises and the Structural Reforms of Korean Government S&T Development Management System (시스템 설계전제의 변화와 공공부문 과학기술발전관리시스템 구조의 개혁)

  • 노화준
    • Journal of Technology Innovation
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    • v.5 no.2
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    • pp.1-21
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    • 1997
  • The objective of this paper is to think about what structural reforms of the Korean government S&T development management system might be. Korean society is currently experiencing a drastic socio-economic transformation. The results of this transformation should be reflected on the determining process of the directions and breadths of structural reforms of government S&T development management system. Because the government system design will be based on the premises of socio-economic conditions under which administrative activities perform and also this socio-economic changes can influence on changes of the premises of government management system design. Moreover, S&T development management system is a subsystem of government system so that the directions of structural reform of those subsystems should be considered in the broad framework changes in the development management system of the government. For the last forty years, the Korean government S&T development management system has been based on the premises including transformation from an agrarian society to an industrial society, authoritarianism and centrally controlled institutions, and exteremely small portions of private investments for science and thechonology R & D of the total. Recently, however, the premises of Korean government S&T development management system have rapidly changed. the characteristics of these changes are including tranformation from an industrial society to a knowledge and information intensive society, globalization, localization, and relatively large portion of private investments for science and technology R & C of the total. The basis of government reforms in Korea was the realization of the performances and values through the enhancement of national competitive capacity, attainment of lean government, decentralization and autonomy. However, the Korean government has attached a symbolic value of strategic organizations representing strong policy intentions of government for the science and technology based development. Most problems associated with the Korean government S&T development management system have grown worse during 1990s. Many people perceive that considerable part of this problem was generated because the government could not properly adapt itself to new administrative environment and the paradigm shift in its role. First of all, the Korean government S&T development management system as a whole failed to develop an integrated vision under which processes in formulating science and thechology development goals and developing consistent government plans concerning science and technology development are guided. Second, most of the local governments have little organizational capacity and manpowers to handle localized activities to promote science and technology in their regions. Third, the measure to coordinate and set priorities to invest resources for the development of science and technology was not effective. Fourth, the Most has been losing its reputation as the symbol of ideological commitment of the top policy maker to promote science and technology. Various ideas to reform government S&T development management system have been suggested recently. Most frequently cited ideas are as follow : (ⅰ)strengthen the functions of MoST by supplementing the strong incentive and regulatory measures; (ⅱ)create a new Ministry of Education, Science & Technology and Research by merging the Ministry of Education and the MoST; (ⅲ)create a new Ministry of Science & Technology and Industry ; and(ⅳ)create a National Science and Technology Policy Council under the chairmanship of the President. Four alternatives suggested have been widely discussed among the interested parties and they each have merits as well as weaknesses. The first alternative could be seen as an alternative which cannot resolve current conflicts among various ministries concerning priority setting and resource allocation. However, this alternatives can be seen as a way of showing the top policymaker's strong intention to emphasize science and technology based development. Second alternative is giving a strategic to emphasize on the training and supplying qualified manpower to meet knowledge and information intensive future society. This alternative is considered to be consistent with the new administrative paradigm emphasizing lean government and decentralization. However, opponents are worrying about the linkages and cooperative research between university and industry could be weakening. The third alternative has been adopted mostly in nations which have strong basic science research but weak industrial innovation traditions. Main weakness of this alternative for Korea is that Korean science and technology development system has no strong basic science and technology research traditions. The fourth alternative is consistent with new administrative paradigms and government reform bases. However, opponents to this alternative are worried that the intensive development of science and technology because of Korea's low potential research capabilities in science and technology development. Considerning the present Korean socio-economic situation which demands highly qualified human resources and development strategies which emphasizes the accumulations of knowledge-based stocks, I would like to suggest the route of creating a new Ministry of Education, Science & Technology and Research by intergrating education administration functions and science & technology development function into one ministry.

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Behavioral Recovery of Sows and Behavioral Development of TheirPiglets Postpartum (분만 후 모돈의 행동적 회복과 포유자돈의 행동적 발달)

  • Jeon, J.H.;Kim, D.J.;Han, J.H.;Yeon, S.C.;Chang, H.H.
    • Journal of Animal Science and Technology
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    • v.45 no.6
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    • pp.1089-1096
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    • 2003
  • We investigated postpartum behaviors of sows and their litters. The aim of this study was to determine the behavioral recovery of sows and the behavioral development of their piglets postpartum. Five multiparous sows(Landrace${\times}$Yorkshire) and their litters were studied over a period of 5 days postpartum. The litter size varied from 8 to 13 with a mean of 11.2 piglets. The behaviors of sows and their piglets were recorded using five CCD cameras, a multiplexer and a time lapsed VCR. The videotapes were scanned every 2 min to obtain an instantaneous behavioral sample. In the behaviors of sows, ‘Lying ventrally’ increased from 1 h postpartum to 26 h postpartum, then decreased gradually, and stabilized after 80 h postpartum. ‘Lying laterally’ decreased from 1 h postpartum to 26 h postpartum and stabilized after 80 h postpartum. ‘Standing, drinking and feeding’ increased from 1 h postpartum to 23 h postpartum, then decreased gradually, and increased again from 60 h postpartum. ‘Sitting’ increased from 1 h postpartum to 46 h postpartum and then decreased. In the behaviors of piglets, ‘Lying’ increased rapidly from 1h postpartum to 45h postpartum, and then was maintained at an almost constant level. ‘Massaging and Suckling’ decreased rapidly from 1 h postpartum to 36 h postpartum, and then was maintained at an almost constant level. ‘Walking’ increased from 1 h postpartum to 21 h postpartum, then decreased gradually. These results suggest that the behavioral recovery of the sow is almost completed at 80h postpartum and that the behavioral development of the piglet is almost completed at 45h postpartum.

Molecular Characterization of Hanwoo Glucose Transporter 4 Gene (한우 Glucose Transporter 4 유전자의 분자생물학적 해석)

  • Lee, S.M.;Jeong, Y.H.;Kim, H.M.;Park, H.Y.;Yoon, D.H.;Moon, S.J.;Chung, E.R.;Kang, M.J.
    • Journal of Animal Science and Technology
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    • v.47 no.6
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    • pp.1087-1094
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    • 2005
  • The uptake of glucose for metabolism and growth is essential to most animal cells and is mediated by glucose transport protein. In the glucose transport protein family, GLUT4 plays a key role in cellular glucose uptake stimulated by insulin in skeletal muscles and adipose tissue in rodents and human. In this studies, we reported the identification, characterization, and expression of Hanwoo GLUT4 gene. The Hanwoo GLUT4 cDNA includes a 1527 bp open reading frame encoding a protein of 509 amino acids. The GLUT4 amino acid sequences of the Hanwoo show strong conservation with the corresponding sequences reported in other species. The highest mRNA expression of GLUT4 was detected in heart and lower expression was detected in rib meat, sirloin, and colon. We confirmed the expression of GLUT4 in the subcutaneous and small intestinal adipose tissue using RT-PCR. To investigate the expression of GLUT4 in the bovine intramuscular adipose differentiation, fibroblast-like cells were isolated from the sirloin of Hanwoo bull aged 12 months by collagenase digestion of minced tissue and cultured with activators of PPAR gamma. We identified that GLUT4 mRNA expression decreased during differentiation of preadipocytes into adipocyte in Korean cattle. These results indicated that function of GLUT4 in bovine adipose tissue was different from that of mouse and human.

Effects of Replacement Sodium Chloride on the Quality Characteristices of Emulsion-type Sausages (대체염 첨가가 유화형 소시지의 품질특성에 미치는 영향)

  • Lee, J.R.;Kwack, S.C.;Jung, J.D.;Hah, Y.J.;Park, K.H.;Cho, H.S.;Sung, N.J.;Park, G.B.
    • Journal of Animal Science and Technology
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    • v.47 no.6
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    • pp.1009-1016
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    • 2005
  • This study was carried out to investigate the effects of substituting NaCl by sodium citrate, potassium lactate and calcium ascorbate (40%) on the quality characteristics of emulsion-type sausages. The pH of emulsion-type sausage of the substitution NaCl with sodium citrate were higher than those of control and the other(P<0.05). The CIE L* value emulsion-type sausage of the substitution NaCl with sodium citrate were higher than those of control and the other(P<0.05). The CIE a* value emulsion-type sausage of the substitution NaCl with potassium lactate were higher than those of control and the other, but CIE b* value were lower(P<0.05). The hardness and gumminess of emulsion-type sausage of the substitution NaCl with sodium citrate were higher than those of control and the other. The Na content of emulsion-type sausage of substitution NaCl with calcium ascorbate were lower than those of control and the other, but Ca content were higher(P<0.05). The K and Fe content of emulsion-type sausage of the substitution NaCl with potassium lactate were higher than those of control and the other(P<0.05). The saltiness of emulsion-type sausage of the substitution NaCl with sodium citrate were higher than those of control and the other(P<0.05). The flavor of emulsion-type sausage of the substitution NaCl with calcium ascorbate were higher than those of control(P<0.05).

Development of a Device for Estimating the Optimal Artificial Insemination Time of Individually Stalled Sows Using Image Processing (영상처리기법을 이용한 스톨 사육 모돈의 인공수정적기 예측 장치 개발)

  • Kim, D.J.;Yeon, S.C.;Chang, H.H.
    • Journal of Animal Science and Technology
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    • v.49 no.5
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    • pp.677-688
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    • 2007
  • 돼지를 포함한 대부분의 동물은 일정한 발정주기를 가지고 일정한 시기에 배란을 하는 자연배란동물이지만, 토끼, 고양이, 밍크 등의 암놈은 교미자극에 의해 배란이 일어나는 유기배란동물이다. 또한 1년에 한 번만 발정하는 단발정동물과 1년에 수차례 발정하는 다발정동물이 있다. 이 중에서 모돈은 1년에 수차례 발정하는 다발정 동물로서 발정기에 들면 비발정기와는 다른 행동을 나타낸다(Diehl 등, 2001). 양돈가의 수익을 최대화하기 위해서는 비생산일수를 최소로 줄여야 한다. 모돈의 비생산일수를 줄일 수 있는 한 가지 방법은 성공적으로 교배를 시키는 것이다. 이처럼 성공적으로 교배를 시키기 위해서는 수정적기를 정확히 예측해야 한다. 만약 수정적기를 정확히 판단하지 못하여 수태가 되지 않으면, 비생산일수가 늘어나 손실을 입게 된다. 따라서 수정적기를 정확히 판단하는 것은 모돈의 성공적인 인공수정에 있어서 중요한 요소이다. 수정적기는 배란이 일어나기 전 10시간에서 12시간 사이이며, 발정이 시작되는 시점을 기준으로 하였을 때 경산돈의 경우 26시간에서 34시간 사이이고 미경산돈의 경우는 18시간에서 26시간 사이이다(Evans 등, 2001). 현재 하루에 두 번 모돈의 발정을 확인하는 것이 일반화되어 있으며, 이 때 웅돈을 접촉시키거나 육안관찰을 통하여 발정 유무를 판단한다. 이러한 방법에는 숙련된 기술과 풍부한 경험이 요구될 뿐만 아니라 총 소요노동력의 30% 정도가 요구된다(Perez 등, 1986). 하루에 두 번밖에 발정을 감지하지 않기 때문에 발정이 언제 시작되었는지를 정확히 알 수 없으며, 또한 발정의 대부분이 새벽에 시작되므로 수정적기를 정확히 판단하기란 매우 어렵다. 만약 발정을 감지했더라도 적기에 인공수정을 하지 못한다면, 수태율이 낮아지므로 경제적 손실이 초래된다. 현재 이러한 문제점 때문에 2회에서 3회에 걸쳐 인공수정을 하고 있으나 이에 따른 소요비용과 소요노동력 등은 양돈가의 부담을 가중시키는 요인이 되고 있다. 돼지는 발정기가 되면 비발정기에 나타내지 않던 외음부의 냄새를 맡는 행동, 귀를 세우는 행동 및 승가허용 행동 등을 나타낸다(Diehl 등, 2001). 또한 돼지는 비발정기에 비하여 발정기에 더 많은 활동량을 나타낸다(Altman, 1941; Erez and Hartsock, 1990). Freson 등(1998)은 스톨에서 개별적으로 사육되고 있는 모돈의 활동량을 적외선센서를 이용하여 측정함으로써 발정을 86%까지 감지하였다고 보고하였다. 그러나 이 연구는 단지 모돈의 발정을 감지하였을 뿐 번식관리에 있어서 가장 중요한 수정적기의 판단 기준을 제시하지 못하였다. 따라서, 본 연구는 스톨에서 사육되는 모돈의 활동량을 측정함으로써 발정시작시각을 감지하고 이를 기준으로 인공수정적기를 예측할 수 있는 인공수정적기 예측 장치를 개발한 후 이의 성능을 농장실증실험을 통하여 시험하고자 수행되었다.

Effects of Caprylic Acid and Cyclodextrin Complex on In vitro Fermentation Characteristics and Methane Production (Caprylic Acid와 Cyclodextrin 복합물이 In vitro 반추위 발효성상 및 메탄 생성에 미치는 영향)

  • Kim, K.H.;Seol, Y.J.;Lee, S.S.;Oh, Y.G.;Nam, I.S.;Kim, D.H.;Choi, C.W.
    • Journal of Animal Science and Technology
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    • v.49 no.5
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    • pp.657-666
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    • 2007
  • This study was conducted to evaluate the effects of dietary addition of caprylic acid(CA)-cyclodextrin (CD) complex on in vitro fermentation characteristics, total gas and methane production. Experiment was done with six treatment groups; 1) no CA-CD complex(control), 2) CA 20 mg(T1), 3) CD 830 mg(T2), 4) CA-CD complex 425 mg(T3), CA-CD complex 850mg(T4), CA-CD complex 1,700 mg(T5). Ruminal pH, ammonia and total VFA concentrations of T2, T3, T4 and T5 were lower(P<0.05) than those of control and T1 for the 12h incubation. The increase in molar percentage of propionate was observed in T4 and T5 compared with control and T2 for the 8h incubation(P<0.05), however, the ratio of acetate to propionate was unchanged in all treatments. Total gas of T1 was lower than that of control, but T2, T3, T4 and T5 were higher compared with control for 12h incubation(P<0.05). If the methane ratio (as %) to total gas for all treatments was compared, T3, T4 and T5(CA-CD supplemented groups) averaged 2.7% whereas control, T1 and T2 showed 3.4, 2.8 and 5.1%, respectively. Therefore, according to these results, it might be concluded that supplementation of CA-CD complex could reduce methane production without disrupting ruminal fermentation.

Construction of X-band automatic radar scatterometer measurement system and monitoring of rice growth (X-밴드 레이더 산란계 자동 측정시스템 구축과 벼 생육 모니터링)

  • Kim, Yi-Hyun;Hong, Suk-Young;Lee, Hoon-Yol
    • Korean Journal of Soil Science and Fertilizer
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    • v.43 no.3
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    • pp.374-383
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    • 2010
  • Microwave radar can penetrate cloud cover regardless of weather conditions and can be used day and night. Especially a ground-based polarimetric scatterometer has advantages of monitoring crop conditions continuously with full polarization and different frequencies. Kim et al. (2009) have measured backscattering coefficients of paddy rice using L-, C-, X-band scatterometer system with full polarization and various angles during the rice growth period and have revealed the necessity of near-continuous automatic measurement to eliminate the difficulties, inaccuracy and sparseness of data acquisitions arising from manual operation of the system. In this study, we constructed an X-band automatic scatterometer system, analyzed scattering characteristics of paddy rice from X-band scatterometer data and estimated rice growth parameter using backscattering coefficients in X-band. The system was installed inside a shelter in an experimental paddy field at the National Academy of Agricultural Science (NAAS) before rice transplanting. The scatterometer system consists of X-band antennas, HP8720D vector network analyzer, RF cables and personal computer that controls frequency, polarization and data storage. This system using automatically measures fully-polarimetric backscattering coefficients of rice crop every 10 minutes. The backscattering coefficients were calculated from the measured data at a fixed incidence angle of $45^{\circ}$ and with full polarization (HH, VV, HV, VH) by applying the radar equation and compared with rice growth data such as plant height, stem number, fresh dry weight and Leaf Area Index (LAI) that were collected at the same time of each rice growth parameter. We examined the temporal behaviour of the backscattering coefficients of the rice crop at X-band during rice growth period. The HH-, VV-polarization backscattering coefficients steadily increased toward panicle initiation stage, thereafter decreased and again increased in early-September. We analyzed the relationships between backscattering coefficients in X-band and plant parameters and predicted the rice growth parameters using backscattering coefficients. It was confirmed that X-band is sensitive to grain maturity at near harvesting season.

Comparison Study of Water Tension and Content Characteristics in Differently Textured Soils under Automatic Drip Irrigation (자동점적관수에 의한 토성별 수분함량 및 장력 변화특성 비교 연구)

  • Kim, Hak-Jin;Ahn, Sung-Wuk;Han, Kyung-Hwa;Choi, Jin-Yong;Chung, Sun-Ok;Roh, Mi-Young;Hur, Seung-Oh
    • Journal of Bio-Environment Control
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    • v.22 no.4
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    • pp.341-348
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    • 2013
  • Maintenance of adequate soil tension or content during the period of crop growth is necessary to support optimum plant growth and yields. A better understanding of soil tension and content for precision irrigation would allow optimal soil water condition to crops and minimize the adverse effects of water stress on crop growth and development. This research reports on a comparison of soil water tension and content variations in differently textured soils over time under drip irrigation using two different water management methods, i.e. pulse time and required water irrigation methods. The pulse time-based irrigation was performed by turning the solenoid valve on and off for preset times to allow the wetting front to disperse in root zone before additional water was applied. The required water estimation method was a new water control logic designed by Rural Development Administration that applies the amount of water required based on a conversion of the measured water tension into water content. The use of the pulse time irrigation method under drip irrigation at a high tension of -20 kPa and high temperatures over $30^{\circ}C$ was not successful at maintaining moisture tensions within an appropriate range of 5 kPa because the preset irrigation times used for water control could not compensate for the change in evapotranspiration during day and night. The response time and pattern of water contents for all of the tested soils measured with capacitance-based sensor probes were faster and more direct than those of water tensions measured with porous and ceramic cup-based tensiometers when water was applied, indicating water content would be a better control variable for automatic irrigation. The required water estimation-based irrigation method provided relatively stable control of moisture tension, even though somewhat lower tension values were obtained as compared to the target tension of -20 kPa, indicating that growers could expect to be effective in controlling low tensions ranging from -10 to -20 kPa with the required water estimation system.