• Title/Summary/Keyword: seeding time

Search Result 434, Processing Time 0.025 seconds

Retention of Endothelial Cells adhered on Polyurethane Surface under Flow Condition

  • Chang, Jun-Keun;Chang, Hyun-A;Kim, Jin-Hee;Kim, Jong-Won;Han, Dong-Chul;Min, Byoung-Goo
    • Journal of Biomedical Engineering Research
    • /
    • v.17 no.3
    • /
    • pp.355-364
    • /
    • 1996
  • Construction of the stable monolayer of endothelial cells onto physicochemically modified polymeric surFace is one of the appropriate method to develop the small caliber vascular graft with the long-term patency. In this study, we constructed the monolayer of endothelial cells on the fibronectin rind the extracellular matrix-coated polyurethane surface derived from human fibroblast cells. To elucidate the adhesion strength of endothelial cells on the extracellular matrix-coated polyurethane, a laminar flow chamber apparatus was developed to exposure the shear stress on the apical membrane of ondothelial cells. Endothelial cells show the strongest adhesion after two days of seeding onto the fibronectin-coated polyurethane surface, whereas endothelial cells on the extracellular matrix derived from the human flbroblast cells show the minimal doubling time of cellular growth.

  • PDF

Impacts of Different Pentachloronitrobenzene (quintozene) Use Patterns on Severity of Damping-off of Ginseng (Panu quinquefolitrs)

  • Reeleder, R.D;Capell, B
    • Journal of Ginseng Research
    • /
    • v.26 no.1
    • /
    • pp.10-16
    • /
    • 2002
  • In replicated field trials, the efficacy of pentachloronitrobenzene (PCNB; quintozene) for control of damping-off of ginseng seedlings was found to be affected by timing of application and formulation. Application at the time of seeding and prior to placement of straw mulch was found to provide the moat consistent level of disease control. However, decline in plant stand during the four-year production cycle resulted in most treatments providing similar levels of plant populations at harvest. Soil residues of pentachloronitrobenzene were generally highest (1 $\mu\textrm{g}$ PCNB/g soil) in those treatments that exhibited the highest levels of disease control in the seedling year. Straw contained high levels of quintozene after application. Beet seed assays with artificially-infested soils indicated that current use rates provide an amount of product suitable for high levels of disease control.

Production of Aerial Conidia of Lecanicillium lecanii 41185 by Solid-State Fermentation for Use as a Mycoinsecticide

  • Vu, Van Hanh;Hong, Suk-Il;Kim, Keun
    • Mycobiology
    • /
    • v.36 no.3
    • /
    • pp.183-189
    • /
    • 2008
  • The production of aerial conidia of Lecanicillium lecanii 41185, a highly virulent fungus, by solid-state fermentation was studied for use as a biocontrol agent against aphids. Among several agro-industrial solid media, steamed polished rice was found to produce the highest amount of aerial conidia. The optimal conditions for aerial conidia production were determined to be a 28.5% moisture content in the rice, 25$^{\circ}C$ culture temperature, rice pH of 6.0, 75% ambient relative humidity, 4-dold seeding culture, 0.6% $KNO_3$, and 12 d of culture time. The conidia yield increased from $5.7\times10^9$ conidia/g polished rice to 18.2 $18.2\times10^9$ conidia/g polished rice following application of these optimized conditions.

Effect of Amount and Time of Nitrogen Top-dressing at Seeding Dates on Growth and Grain Yield of Soybeans (대두(大豆)의 파종기별(播種期別) 질소추비량(窒素追肥量)과 추비시기(追肥時期)가 생육(生育) 및 수량(收量)에 미치는 영향(影響))

  • Lee, Chung Yeol;Choi, Chang Yeol
    • Korean Journal of Agricultural Science
    • /
    • v.14 no.1
    • /
    • pp.1-15
    • /
    • 1987
  • This experiment was conducted to investigate the effect of nitrogen top-dressing and Jangyeopkong was planted under two different seeding time (single cropping-May 15, after barley cropping-June 18), four levels of nitrogen top-dressing (0, 3, 6, 9 kg/10a) and two times of nitrogen top-dressing (Hilling time, Flowering Time). The results obtained are summarized as follow: 1. The days to flowering and maturity were delayed a day longer in hilling times than flowering times of nitrogen top-dressing. 2. The number of nodes of main stem and length of internodes didn't show significance among treatments. But, the number of nodes of branches was much higher when the soybean was planted on May 15, and were higher hilling time than flowering time as the amount of nitrogen top-dressing increased. Especially, the number of nodes of branches was high when 6kg of nitrogen was applied during hilling time. 3. The fresh and dry weight of stem and leaves at 10, 25 and 40 days after flowering were increased by increasing the amount of nitrogen top-dressing. More apparent effect of nitrogen was attained high significant when nitrogen was applied at the time of hilling rather than flowering time. 4. The number and fresh weight of nodule, and dry weight were apparently decreased after barley and were decreased according to the increasing the amount of nitrogen top dressing. The degrees of decreasing was more apparent in the hilling time than in the flowering time. 5. The number of pods per plant, and number and weight of grain per plant were higher when the soybean was planted on May 15, the amount of top dressing increased and hilling time rather than flowering time. Especially, yield component were highest when 6kg of nitrogen was applied during hilling time. Also, the grain yield per 10a showed high significance among treatment, and were high when 6kg of nitrogen was applied during hilling time.

  • PDF

Studies on the Response to Day-length and Temperature and their Effects on the Yield of Perilla (Perilla ocimoides L.) (들깨의 일장 및 온도에 대한 감응성과 그의 수량에 미치는 영향에 관한 연구)

  • Ik-Sang Yu
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.17
    • /
    • pp.79-114
    • /
    • 1974
  • Experiments were conducted to clarify the variations of the ecological characteristics under different day-length and temperature conditions inperilla varieties from 1972 to 1973 in the experimental fields of Crop Experiment Station, O.R.D, Suwon. Thirty-six varieties were tested in the field in 1972 under 6 growing seasons differing seeding dates. from April 5th to June 20th with 15-day interval between each seeding. Pot-experiment also were conducted in 1972 and 1973. The seeds of the 6 varieties tested were sown on May 25th. In this pot-experiment natural condition was regarded as a short-day treatment and 100-W incandescent lamps were used for long-day treatment. Three selected varieties were grown under different. temperature treatments in phytotron in Crop Experiment Station. The results obtained are summarized as follows: 1. Most varieties tested flowered around September 6. The days required to flower were shortened gradually as the planting time was delayed. 2. The varieties used were matured around October 6, but the maturity was shortened when planted early. The days required for maturity after flowering was 26 to 30. 3. The growing period was also shortened gradually when planting time was delayed. 4. Plant height was reduced when planting time was delayed. 5. There were little differences in number of valid branches among planting time I, II and III, while the branch number was reduced as the planting time was delayed. 6. The dry matter weight was gradually increased from planting time I to III, while it was rapidly decreased after planting time IV. 7. It was found that the flowering of perilla was little affected by temperature. The varieties, however, were more sensitive to day-length. 8. No clear tendency was found in the plant height, number of valid branches and dry matter weight by the time and period of day-length and temperature treatments. 9. The highest yield was obtained at planting time III(May 5th) and the yield was decreased at either earlier or later planting. 10. 1, 000 grain weight appeared to be heavier as the planting time was delayed. 11. The number of flower cluster was largest at planting time III (May 5th) and it was decreased as planting time was earlier or later than III. 12. The oil content was also highest at planting time III (May 5th). 13. Days to flowering, days to maturity and total growing period and flowering period did not affect the yield much. 14. The number of valid branches, flower clusters, 1, 000-grain weight and dry matter weight were positively correlated with yield. The relationship between these characters and yield were variable depending upon the planting time.

  • PDF

The effect of seeding on crystal growth of NaX zeolite (NaX zeolite의 결정성장에서 seed 첨가에 따른 영향)

  • 하종필;김익진
    • Journal of the Korean Crystal Growth and Crystal Technology
    • /
    • v.9 no.1
    • /
    • pp.6-13
    • /
    • 1999
  • NaX zeolite crystal were grown from seed elements of synthetic NaX(2~3$\mu\textrm{m}$) Powder in a mother liquor having an approximate reactant composition ${4.12{Na}_{2}O{\cdot}{Al}_{2}{O}_{3}{\cdot}3.5{SiO}_{2}{\cdot}593{H}_{2}O$.The result was that crystallization time of NaX zeolite was reduced with adding seed materials to the initial mixture and crystal size was reduced . but with increasing crystallization time, NaX zeolite. In this study, We investigated detailed factors which NaX crystal has been determined by a combination of SEM, XRD, FT-IR, and BET.

  • PDF

Comparisons of Chemical Composition and Forage Yield Among Winter Green Manure Crops (동계 녹비작물 초종별 화학성분 및 생산성 비교)

  • 서정호;이호진;허일봉;김시주;김충국;조현숙
    • Journal of The Korean Society of Grassland and Forage Science
    • /
    • v.20 no.3
    • /
    • pp.193-198
    • /
    • 2000
  • Plant characteristics of four winter crop hairy vetch, red clover, crimson clover and rye as green manure were evaluated at three harvesting time(Apri1 23, May 9, May 28) in spring to select superior winter green manure crop. Rye and hairy vetch had superior wintering ability and produced high dry matter compared with crimson clover and red clover. But N amount of rye was small because of its low plant N% despite of early dry matter accumulation. Wintering ability of crimson clover was very poor, so its dry matter decreased rapidly with low seeding rate. Hairy vetch had high N % (4%, C:N ratio 11) and produced high N yield among four plant. It is estimated that hairy vetch have high N-fixing ability because its N% was not changed largely despite of dry matter accumulation at late harvesting time contrast to the other legume. It was thought that hairy vetch was superior green manure crop in considering yield of dry matter and N. (Key words : Winter legumes, Hairy vetch, Green manure yield, Nitrogen concentration)

  • PDF

Overwintering Capacity Affected by Seeding Time and Method of Chinese Milk Vetch, Astragalus sinicus L., in Upland Field

  • Lee Ji Hyun;Kang Byeung Hoa;Shim Sang In
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.50 no.2
    • /
    • pp.67-72
    • /
    • 2005
  • Overwintering capacity, closely related to winter hardiness, of Chinese milk vetch planted with different sowing times and sowing practices was investigated to improve the incorporation into cropping system in Korea. The tolerance to low temperature was evaluated with $LT_50$ using leaf disc leaching method. Dry weight of CMV was reduced remarkably with delayed planting from Sep. 5 to Oct. 20. The differences in tolerance to freezing temperature were not conspicuous among CMV genotypes, however, the differences between genotype (collections at different regions) were due to the plant architecture, mainly to the leaf angle. The crouching genotype collected at central region of Korean peninsula, which showed excellent freezing tolerant, has planophile leaves. The feature of internal constituents of CMV genotypes did not show any noticeable differences with respect to the freezing tolerance which evaluated by leaf disc leaching experiment. To overcome the poor overwintering capacity, tolerant genotype should be developed by selection with considering the plant architecture. The reduction of CMV growth during overwintering period was ameliorated with furrow-sowing under late-sown condition, therefore, when the CMV is inevitably sown late after recommended time, the seeds should be sown on furrow to overcome the cold stress.

Seed Production Studies in Italian Ryegrass ( Lolium multifiorum Lam. Italicum ) III. Effects of Autumn and Spring Defoliation on Seed Yield of Italian Ryegrass (이탈리안 라이그라스의 종자생육에 관한 연구 III. 추.춘 청예이용이 종실수량에 미치는 영향)

  • 박병훈;박희길;배상태;강정훈;이남종
    • Journal of The Korean Society of Grassland and Forage Science
    • /
    • v.7 no.1
    • /
    • pp.49-54
    • /
    • 1987
  • Information is needed on the plant characteristics affects by forage removal and their relationships to grain yield of italian ryegrass in order to combine herbage seed crop management and livestock farming. This study with tetraploid cv. Tetrone was carried out on the experimental field of Haenam Branch Station. treatments included two different seeding time, cutting time and frequency. Seeds were sown in row 50 cm width within the rows. The results are summarized as follows: 1. Fresh and dry matter were increased significantly in plots defoliated lately and many times but seed yield components were decreased significantly in plots defoliated in spring. 2. Autumn defoliation had no significant effect on the seed yield but seed yield were decreased significantly in plots defoliated later than 8 April. 3. Excess vegetative growth can be removed in autumn and early spring without harm to the seed crop and the most important aspect of its removal is the timing of the operation. 4. Seed yield reductions were accompanied by the decrease of inflorescences,seeds/spike, and thousand seeds weight, due to an increase in apex removal of vigorous tillers by late cutting.

  • PDF