• Title/Summary/Keyword: seed bed

Search Result 113, Processing Time 0.021 seconds

User industry and accumulation of technological capabilities of producers-Finnings from the Korean machine tool industry

  • 임채성
    • Proceedings of the Technology Innovation Conference
    • /
    • 2001.06a
    • /
    • pp.71-95
    • /
    • 2001
  • This study reveals that the user industry has a limited role as a source of technological capability in the case of the machine tools in Korea where the user industry is relatively mope advanced than other capital goods industry. The study examined the sources of technological capability in terms of migration of workforce and flow of product design information. Although the capital goods sector is generally regarded as being the sector where the user producer interaction is important the user industry failed to be the seed-bed of technological capability to develop machines. This study argues that this finding could have implications to the specificity of capital goods in a developing country.

  • PDF

Perspective of breaking stagnation of soybean yield under monsoon climate

  • Shiraiwa, Tatsuhiko
    • Proceedings of the Korean Society of Crop Science Conference
    • /
    • 2017.06a
    • /
    • pp.8-9
    • /
    • 2017
  • Soybean yield has been low and unstable in Japan and other areas in East Asia, despite long history of cultivation. This is contrasting with consistent increase of yield in North and South America. This presentation tries to describe perspective of breaking stagnation of soybean yield in East Asia, considering the factors of the different yields between regions. Large amount of rainfall with occasional dry-spell in the summer is a nature of monsoon climate and as frequently stated excess water is the factor of low and unstable soybean yield. For example, there exists a great deal of field-to-field variation in yield of 'Tanbaguro' soybean, which is reputed for high market value and thus cultivated intensively and this results in low average yield. According to our field survey, a major portion of yield variation occurs in early growth period. Soybean production on drained paddy fields is also vulnerable to drought stress after flowering. An analysis at the above study site demonstrated a substantial field-to-field variation of canopy transpiration activity in the mid-summer, but the variation of pod-set was not as large as that of early growth. As frequently mentioned by the contest winners of good practice farming, avoidance of excess water problem in the early growth period is of greatest importance. A series of technological development took place in Japan in crop management for stable crop establishment and growth, that includes seed-bed preparation with ridge and/or chisel ploughing, adjustment of seed moisture content, seed treatment with mancozeb+metalaxyl and the water table control system, FOEAS. A unique success is seen in the tidal swamp area in South Sumatra with the Saturated Soil Culture (SSC), which is for managing acidity problem of pyrite soils. In 2016, an average yield of $2.4tha^{-1}$ was recorded for a 450 ha area with SSC (Ghulamahdi 2017, personal communication). This is a sort of raised bed culture and thus the moisture condition is kept markedly stable during growth period. For genetic control, too, many attempts are on-going for better emergence and plant growth after emergence under excess water. There seems to exist two aspects of excess water resistance, one related to phytophthora resistance and the other with better growth under excess water. The improvement for the latter is particularly challenging and genomic approach is expected to be effectively utilized. The crop model simulation would estimate/evaluate the impact of environmental and genetic factors. But comprehensive crop models for soybean are mainly for cultivations on upland fields and crop response to excess water is not fully accounted for. A soybean model for production on drained paddy fields under monsoon climate is demanded to coordinate technological development under changing climate. We recently recognized that the yield potential of recent US cultivars is greater than that of Japanese cultivars and this also may be responsible for different yield trends. Cultivar comparisons proved that higher yields are associated with greater biomass production specifically during early seed filling, in which high and well sustained activity of leaf gas exchange is related. In fact, the leaf stomatal conductance is considered to have been improved during last a couple of decades in the USA through selections for high yield in several crop species. It is suspected that priority to product quality of soybean as food crop, especially large seed size in Japan, did not allow efficient improvement of productivity. We also recently found a substantial variation of yielding performance under an environment of Indonesia among divergent cultivars from tropical and temperate regions through in a part biomass productivity. Gas exchange activity again seems to be involved. Unlike in North America where transpiration adjustment is considered necessary to avoid terminal drought, under the monsoon climate with wet summer plants with higher activity of gas exchange than current level might be advantageous. In order to explore higher or better-adjusted canopy function, the methodological development is demanded for canopy-level evaluation of transpiration activity. The stagnation of soybean yield would be broken through controlling variable water environment and breeding efforts to improve the quality-oriented cultivars for stable and high yield.

  • PDF

Growth and Yield According to Wick Number Under Wick Culture System of Potato Plug Seedlings (감자 플러그묘 심지재배에서 심지수에 따른 상위급종서의 생산성)

  • 강봉균;송창길;김찬우;박정식;문현기;오태수;오문학
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.48 no.3
    • /
    • pp.191-195
    • /
    • 2003
  • This study was conducted in 2001 to develop a technique for mass production of superior seed tuber by using a wick culture system as an alternative plan to solve problems in hydroponic culture of potato. Potato (Solanum tuberosum L. cv. Dejima) plug seedings were planted on a styrofoam bed (volume $0.032\textrm{m}^3$) containing two different media (Jeju scoria + peatmoss and perlite + peatmoss, (1:2, v/v) mixture, respectively). Each bed was equipped with various number of wicks (2, 4, 6, 8 and 10 ea/bed). After harvest, the total porosity of both media was 83-85%. Bulk density of Jeju scoria + peatmoss was higher compared to that of perlit + peatmoss. However, the number of wicks did not influence to the bulk density. Conversely, moisture capacity of Jeju scoria + peatmoss was remarkably greater than that of perlite + peatmoss and was increased from 55 to 70% as elevating number of wicks. Although the number of wicks resulted in the areal growth of plants, the total yield and the weight of tuber were highest at the bed equipped with six wicks in both media.

Effect of Gibberellin and Chilling Treatments on Breaking Epicotyl Dormancy and Seedling Growth of Polygonatum odoratum Druce (둥굴레의 상배축(上胚軸) 휴면타파(休眠打破)와 유묘생장(幼苗生長)에 대한 지베렐린 및 저온 처리효과)

  • Kang, Jin-Ho;Kim, Dong-Il;Bae, Kee-Soo;Kim, Seok-Hyeon;Chung, Jong-Il
    • Korean Journal of Medicinal Crop Science
    • /
    • v.7 no.1
    • /
    • pp.16-21
    • /
    • 1999
  • Seed-propagation of Solomon's seal (Polygonatum odoratum) takes 2 years to shorten the period for becoming a practical method. The experiment was done to establish a proper method of breaking the epicotyl dormancy in bulk seed-propagation. Seedlings with a bulbil were treated with $GA_3$ every 2 days for 4 or 8 days and chilling treatments at $3^{\circ}C$ were enforced for 4, 6, 8 or 12 weeks. Emergence- and growth-related characteristics were examined immediately after the treatments, 3 and 6 weeks later. Rate of cotyledonary sheath rupture immediately after $GA_3$ treatment was greater in its 8-day treatment than in 4-day although its effect disappeared later. However, any epicotyl treated with $GA_3$ solution did not elongate so that new seedlings disemerged over the bed soil. That resulted from not breaking the epicotyl dormancy since $GA_3$ did not rupture all of the cotyledonary sheath formed with several sheets and consequently, the solution did not reach it. The $GA_3$ treatment for bulk seed-propagation, therefore, was impractical method. On the contrary, the chilling treatment was able to be applied to the seed-propagation because of getting the cotyledonary sheath rupture and the epicotyl elongation. Seedling emergence and its growth after chilling treatment were influenced by chilling period although required at least over 6-week treatment for satisfactory results.

  • PDF

Augmentation and Monitoring of an Endangered Fish, Gobiobotia naktongensis in Naeseongcheon Stream, Korea (내성천에서 멸종위기어류 흰수마자 Gobiobotia naktongensis의 증강도입과 모니터링)

  • Na, Jin-Young;Choi, Byoung-Seub;Hwang, Sang-Chul;Yang, Hyun
    • Ecology and Resilient Infrastructure
    • /
    • v.2 no.3
    • /
    • pp.216-223
    • /
    • 2015
  • The conservation project to protect an endangered fish, Gobiobotia naktongensis was executed against declining the gene diversity of the fish after the construction of Youngju Dam in a sand-bed stream (Naeseongcheon Stream). We tried to move the populations of G. naktongensis from submerged planned sites to alternative habitats, bred artificially and augmented the juveniles to optimal habitat, and monitored the results of the restoration implementation. No entity of G. naktongensis was confirmed at the planned submerged sites despite attempting to capture more than 8 times and eventually the movement to alternative habitat could not be implemented. About 40 individuals of G. naktongensis were captured in the Naeseongcheon Stream and a total of 5,000 individuals were artificially spawned up. The population of juvenile inherited the genetic diversity from the brood stock. The bred juveniles were discharged at the selected optimal site that had a habit condition what was similar to their natural habitat. The micro-dispersion around the discharging area was found at the early stages of the augmentation. The re-capturing rate of discharged juveniles was reduced as time passed. The discharged juveniles seemed to adapt to the natural environment of Naeseongcheon Stream. The observation of their high abdominal distension and excrement demonstrated that the juveniles fed successfully in the discharging area. Therefore, securement of genetic homogeneity and enhancement of restoration population of G. naktongensis in upstream and downstream of Youngju Dam site from the artificial seed producing seemed to be primarily successful and long-term monitoring and analysis of the effect was expected to be necessary.

Rice Seedling Establishment for Machine Transplanting VI. Effect of Mulching Materials on Raising Rice Seedling at Tray for Machine Transplanting (수도 기계이앙 육묘에 관한 연구 Ⅵ.제6보 상자육묘시 피복자재이용 효과)

  • Yun, Yong-Dae;Yang, Won-Ha;Kwang, Yong-Ho;Park, Seok-Hong;Park, Rae-Kyeong
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.31 no.1
    • /
    • pp.9-15
    • /
    • 1986
  • To establish an efficient light control method using three covering materials on tunnel shaped rice seed-bed at greening stage after seedling emergence, four rice cultivars, Nampungbyeo, Taebaegbyeo, Seonambyeo, and Seomjinbyeo were sown on 15 April and 10 May in 1983 and 1984 respectively. After seedling emergence by a simplified emerging methods the seedling boxes were moved onto tunnel shaped seed-bed which was covered with combined matrials of PE film, silverpoly sheet, and spunbonded polyester fabric. For machine transplanting of rice seedlings in cases of early season and optimum season seeding in central part of Korea, PE film tunnel with silverpoly mulched, and PE film tunnel methods with spunbonded polyester fabric mulched reduced injuries of non-parasitic seedling damping-off and a albinism as affected by it, protected rice seedlings from injuries by extremely low temperature in the night, and reduced less differences in diurnal temperature than those in the other covering methods. At late season seeding for double cropping system of paddy field in southern part of Korea, a single silver-poly or a single spunbonded polyester fabric-covered tunnel method showed good green seedlings, and prevent-ed extreme rising of diurnal temperature by light interception in the tunnel.

  • PDF

Effects of Nursery Condition on the Establishment and the Growth of Sesame Seedling (참깨묘 양성조건이 활착 및 생육에 미치는 영향)

  • Jung-Il Lee
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.28 no.3
    • /
    • pp.386-389
    • /
    • 1983
  • An experiment was conducted to establish the appropriate tranaplanting method of sesame seedlings. Covering of polyethylene film on nursery bed resulted in more adventitious roots and better growth after transplanting. Nursery soil showed the best results when it was mixed with the equal amounts of soil, sand and compost. The most healthy seedlings were raised by spot seeding of 5${\times}$5 cm distance and 4 cm bed-depth. Compared to direct seeding on June 15, sesame seeded on June 10 followed by transplanting on June 30 flowered 4 days earlier and produced more capsules per plant and 18% more seed yields.

  • PDF

Controlled Release of Nifedipine in Multi-layered Granule System (다중층 과립 시스템에서 니페디핀의 방출 제어)

  • Lee, Soo-Young;Youn, Ju-Yong;Kim, Byung-Soo;Kim, Moon-Suk;Lee, Bong;Khang, Gil-Son;Lee, Hai-Bang
    • Journal of Pharmaceutical Investigation
    • /
    • v.37 no.4
    • /
    • pp.229-235
    • /
    • 2007
  • Multi-layered granules were prepared by a fluidized-bed coater and uniformed granules were obtained with a size range between $950{\sim}1000{\mu}m$ in diameter. The granule system was composed of three layers, i.e. seed layer with sugar sphere bead and a water-swellable polymer, middle layer with a drug, solubilizer and polymer, and the top layer of porous membrane with a polymeric binder. The aim of this work is to find out the dependence of a drug dissolution rate on the amount of a water-soluble binder and a solubilizer in the granule system. The results showed that the higher amount of hydrophilic binder in the porous membrane, gave the bigger pore size and porosity and made faster dissolution rate and also the higher amount of solubilizer in drug layer enhanced the dissolution rate of drug.

Light environment and physiological response of Panax ginseng I. Experience on light in natural habitat,through cultivation under forest and artificial shade, and change of light control technique (인삼의 광환경과 생리반응 I.자생지. 임간 및 일복 재배에서 광경험과 광조절 방법의 변천)

  • Park, Hoon
    • Journal of Ginseng Research
    • /
    • v.7 no.2
    • /
    • pp.172-192
    • /
    • 1983
  • Light environment and growth of Panax ginseng In habitat and cultivation under natural shade were renewed. Grower's experiences on ginseng stand In relation to light environment were assessed. Change of shading method and grower's concepts on light requirement of ginseng plant in Korea, Manchuria and Japan was counted. Growth of wild ginseng was better under rich light. Optimum crown density index appeared to be 0.7 In natural habitat and 0.4 to 0.7 for the cultivation in forest. Change of light Intensity in forest was greatest in May and reached near to constant value (from 40% to 3% for broad leaf deciduous forest and loom 4% to 2% for pine forest). Insufficient light condition induced long and thin stem, poor flowering and seed bearing, and sequent dormancy. Relation between light and ginseng strand was not clear but light Interception with cool weather was effective. Topography and orientation of bed have been deeply considered for light environment. Panel or bark of won were used for shading in deep forest manly In Manchuria while reed blind and straw thatch were used in Korea. Kinds and number of shades material and seasonal or daily schedule have been simplified probably by labor pressure due to eulargement of plantation. Post height has been greater while width of roof, bed and ditch has changed lisle. Scientific survey in the past omitted important light control methods (complete light hardening etc) which has been practiced in specific areas. The concept and technique of light control in the past in Korea were delicate and intensive including the control of temperature and moisture. For the application of old concept in modem cultivation precise Investigation of the technique including the measurement of light, temperature and moisture is needed.

  • PDF

Sensitivity Analysis of the Factors Affecting Traffic Micro-simulation Results (교통 미시 시뮬레이션 결과에 영향을 미치는 요소의 민감도 분석)

  • Kim Kyu-Ok;Shin Chi-Hyun
    • The Journal of The Korea Institute of Intelligent Transport Systems
    • /
    • v.4 no.2 s.7
    • /
    • pp.53-66
    • /
    • 2005
  • Microscopic simulation models, which focus on individual vehicles, are used extensively in the transportation operations in order to capture vehicle to vehicle and vehicle to traffic controls. There are many important factors involved when a micro simulation model is applied as an evaluation tool for the traffic system. They typically include test bed, software, simulation time period, measure of effectiveness, parameter for a software, OD matrix, and random seed number. To evaluate the effects of those factors, sensitivity analysis was performed to identify the effects of those factors based on CORSIM and TRANSIMS results. Three freeway corridors, two in Houston (I-10 and US 290) and one in Sin Antonio (I-37), were chosen as test beds. Three time periods (AM, PM, off-peak) and three OD matrix estimates were used for the analysis. It was found that the micro-simulation results were highly sensitive to the model Parameter sets and the OD information. The degree of sensitivity was a function of the test bed and time period.

  • PDF