• Title/Summary/Keyword: 농업생산성

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Response of Growth and Functional Components in Baby Vegetable as Affected by LEDs Source and Luminous Intensity (LEDs 광조성 및 광도가 베이비채소의 생육 및 기능성물질에 미치는 영향)

  • Yoon, Seong-Tak;Jeong, In-Ho;Kim, Young-Jung;Han, Tae-Kyu;Yu, Je-Bin;Jae, Eun-Kyung
    • Korean Journal of Organic Agriculture
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    • v.23 no.3
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    • pp.549-565
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    • 2015
  • This study was conducted to investigate the growth characteristics and functional materials of baby vegetables as affected by different LEDs and luminous intensity at Anseongsi, Gyeonggi Province, in 2014. Test crops were beet, chicory, spinach, red leaf lettuce, crown daisy and red mustard purchased from the seed company of Dongbu Hannong and Jinheung. Growth characteristics were measured and the content of functional materials was analyzed 40 days after seeding at plug plate. Treatment of Red+Blue (4:1) at $150{\mu}mol\;m^{-2}s^{-1}$ luminous intensity showed the highest number of leaves in five baby vegetables of beet, chicory, red leaf lettuce, crown daisy and red mustard. The highest shoot length of chicory, spinach, red leaf lettuce, crown daisy and red mustard was obtained from the treatment of Red+Blue (4:1) at $150{\mu}mol\;m^{-2}s^{-1}$ luminous intensity. Fresh weight and dry weight of all six baby vegetables were the highest in treatment of Red+Blue (4:1) at $150{\mu}mol\;m^{-2}s^{-1}$ luminous intensity. Content of chlorophyll a and chlorophyll b of spinach, red leaf lettuce and red mustard showed the highest in Fluorescent lamp at $150{\mu}mol\;m^{-2}s^{-1}$ luminous intensity whereas other crops did not show definite trend under different LEDs lights and luminous intensity. The highest total content of anthocyanins and polyphenol were obtained from the treatment of Red+Blue (4:1) at $150{\mu}mol\;m^{-2}s^{-1}$ luminous intensity in all six baby vegetables. Free radical scavenging activity was highest in all six vegetable crops at $150{\mu}mol\;m^{-2}s^{-1}$ luminous intensity, but it was not different significantly between LEDs. As a result, the growth and the content of functional material of baby vegetables are generally to be increased in Red+Blue (4:1) at $150{\mu}mol\;m^{-2}s^{-1}$ luminous intensity. Mixed light of Red+Blue is thought to give good effect on the growth and the content of functional material in baby vegetable crops. Because there are many differences in regard of LED lights, crop varieties, cultivation and experimental methods in their impact on the growth and functional materials of baby vegetables among researchers, it is considered that a more precise studies are needed for the crop responses to LED light and luminous intensity.

Effects of Mixture Application of Concentrated Pig Slurry and Byproduct Liquid Fertilizer on the Growth and Yield of Chinese Cabbage (돈분뇨 농축액비와 부산물액비 혼합시용이 배추의 생육과 수량에 미치는 영향)

  • Ryoo, Jong-Won
    • Korean Journal of Organic Agriculture
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    • v.18 no.2
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    • pp.271-282
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    • 2010
  • This study was conducted to investigate the effects of concentrated pig slurry and byproduct liquid fertilizer on the growth and yield of chinese cabbage. The experiment was conducted in a rain-shelter house which was installed in the agriculture farm. Plants were fertilized with concentrated slurry (CS), byproduct fertilizer (BF), mixture of concentrated slurry and byproduct liquid fertilizer (CS+BF), combined organic and chemical fertilizer (CS+BF+BF) and chemical fertilizer (CF) as control. 1. The pH level of byproduct liquid was decreased from the 3rd to the 7th day and increased 9 day to 14th day, but pH of concentrated slurry (CS) was not greatly varied. EC of concentrated slurry (CS) and byproduct liquid was increased gradually during the fermentation. 2. The concentrated slurry (CS) was low in phosphorus, calcium, magnesium, rich in potassium and unbalanced as a low nitrogen and high potassium. But byproduct liquid fertilizer was balanced in nitrogen and potassium ratio. 3. The leaf number, head height, head width of chinese cabbage in treatment with organic and chemical fertilizer (CS+BF+N) showed significant difference compared with control. The plant and head weight of chinese cabbage in treatment of concentrated slurry was severely decreased, but that in treatment organic and chemical fertilizer (CS+BF+N) were increased 8, 10% compared with control chemical fertilizer (CF), respectively. 4. The content of $K_2O$ in plant tissue and in soil was increased after using concentrated slurry. On the other hand, mineral content of except $K_2O$ did not differ significantly between any of the treatments. In conclusion, organic and chemical fertilizer (CS+BF+N) could improve growth and head weight of chinese cabbage.

Physico-chemical and Sensory Characteristics of Cooked Sausage Substituted with KCl or MgCl2 for NaCl (KCl 또는 MgCl2의 NaCl 대체 소시지의 이화학적 및 관능적 특성)

  • Jin, Sang-Keun;Kim, Il-Suk;Hur, In-Chul;Nam, Sang-Hae;Kang, Suk-Nam;Shin, Daekeun
    • Journal of agriculture & life science
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    • v.45 no.5
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    • pp.81-89
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    • 2011
  • This study was carried out to investigate changes in physicochemical and sensory properties of cooked sausages replaced sodium chloride (NaCl) to potassium chloride (KCl) or magnesium chloride ($MgCl_2$) during storage for 30 days under $4^{\circ}C$. All sausages were prepared with different combination of salts as follow; CTL (1.5% NaCl), KCL (0.9% NaCl+0.6% KCl), MCL (0.9% NaCl+0.6% $MgCl_2$), KML (0.9% NaCl+0.3% KCl+0.3% $MgCl_2$) and PST (1.5% PanSalt). Among sausages moisture content in KML was the highest (p<0.05). Lightness and redness in CTL were lower than those of other treatments, but MCL and KML containing $MgCl_2$ showed higher CIE $L^*$ and $a^*$ values than CTL. The pH in CTL was the highest during storage, however, no significant difference was determined between two treatments, MCL and KML (p>0.05). Crude fat content and water holding capacity (WHC), hardness and cohesiveness of MCL sausages were higher than those of CTL. In sensory characteristics of cooked sausages, saltness in MCL was the lowest during 10 and 20 days of storage (p<0.05). Yellowness in PST was lower than other treatmeants. Gumminess and chewiness of texture property of sausages from MCL and KML were higher than CTL. The results indicate that the replacement of NaCl by KCl improved texture, but meat color was not improved as expected. In contrast, the replacement of NaCl by $MgCl_2$ enhanced color, texture and WHC, whereas partial replacement of NaCl by $MgCl_2$ must reduce bitter taste as compared to sausages manufactured with a NaCl only. Therefore, $MgCl_2$ may be a salt replacing NaCl in cooked pork sausages.

『Chūn-qiū』Wáng-lì(『春秋』王曆)➂ - from Zhōu-lì(周曆) to Xià-lì(夏曆), and "Xíng-xià-zhī-shí(行夏之時)" Mentioned by Confucius (『춘추』 왕력(王曆)➂ - 주력(周曆)에서 하력(夏曆)으로, 그리고 공자의 "행하지시(行夏之時)")

  • Seo, Jeong-Hwa
    • The Journal of Korean Philosophical History
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    • no.54
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    • pp.153-184
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    • 2017
  • During the Pre-Qin(秦) Dynasty era, there were the records that there had been many calendar systems, such as $g{\check{u}}-li{\grave{u}}-l{\grave{i}}$(古六曆 : six ancient calendar systems). Then, the fact that particularly $zh{\bar{o}}u-l{\grave{i}}$(周曆) and $xi{\grave{a}}-l{\grave{i}}$(夏曆) were mainly discussed among them resulted from a lot of discussions from the differences in the calendar system in "$Ch{\bar{u}}n-qi{\bar{u}}$(春秋)" known to have been written by Confucius from the calendar system in "$X{\acute{i}}ng-xi{\grave{a}}-zh{\bar{i}}-sh{\acute{i}}$(行夏之時 : implement the calendar of Ha dynasty.)" that Confucius mentioned himself to his disciple. $zh{\bar{o}}u-l{\grave{i}}$(周曆) with $d{\bar{o}}ngzh{\grave{i}}-yu{\grave{e}}$(冬至月 : the 11th month of the lunar calendar) as the first month of a year had the system of the lunar calendar, and $xi{\grave{a}}-l{\grave{i}}$(夏曆) called as the calendar of Ha(夏) dynasty had the system of $ji{\acute{e}}-q{\grave{i}}-l{\grave{i}}$(節氣曆 : a kind of the solar calendar that divides one year of 365 days into 24 solar terms) with $y{\acute{i}}n-yu{\grave{e}}$(寅月 :one month from the present Feb 5) as the first month of a year. These two calendars had definite differences in the first months of a year, names of seasons, and the lunar calendar and the solar calendar. The fundamental reason why Confucius recommended the performance of $xi{\grave{a}}-l{\grave{i}}$(夏曆) as a way to run the nation was not that it started from the philosophical view of the universe that among the 'three $zh{\bar{e}}ng$'(三正)' of $ti{\bar{a}}n-zh{\bar{e}}ng$(天正 : the first month of a year with the heaven as the standard), $d{\grave{i}}-zh{\bar{e}}ng$(地正 : the first month of a year with the earth as the standard) and $r{\acute{e}}n-zh{\bar{e}}ng$(人正 : the first month of a year with humans as the standard), but that he wanted to emphasize the importance of practical national economic policies to enhance agricultural productivity. It becomes the criterion that even though Confucius emphasized that politicians should not have moral flaws ideally, with regard to public policies, he wanted to stress politicians' duties based on the reality a lot.

Effect of Shading and Supplemental Lighting for Greenhouse Cultivation of Cucumber in Summer Season (하절기 오이 온실재배 시 차광 및 보광 효과)

  • Jin Yu;Ji Hye Yun;So Yeong Hwang;Eun Won Park;Jeong Hun Hwang;Hyeong Eun Choi;Jeong Kil Koo;Hee Sung Hwang;Seung Jae Hwang
    • Journal of Bio-Environment Control
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    • v.32 no.3
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    • pp.226-233
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    • 2023
  • High solar radiation in summer season causes excessive respiration of crops and reduces photosynthesis. In addition, the rainy season, which mainly occurs in summer, causes a low light condition inside the greenhouse. A low light condition can reduce crop growth and yield. This study was conducted to evaluate the effect of shade and supplemental lighting on the growth and yield of cucumber during summer season. Cucumber grafted seedlings were transplanted in two plastic greenhouses on August 30, 2022. To reduce the light intensity inside the greenhouse, a 50% shading screen was installed in one greenhouse. Supplemental lighting was conducted from September 7, 2022 to October 20, 2022. HPS (high-pressure sodium lamp), W LED (white LED, red:green:blue = 5:3:2), and RB LED (combined red and blue LED, red:blue = 7:3) were used for supplemental lighting sources, and non-treated (nonsupplemental lighting) was as the control. The supplemental lighting was conducted before sunrise and after sunset for 2 hours with a photosynthetic photon flux density of 150 ± 20 µmol·m-2·s-1. The plant height, leaf length, leaf width, and SPAD value tended to increase in the shading group. RB LED increased stem diameter regardless of shading treatment. Fresh and dry weights of fruits were not significantly different in shading and supplemental lighting. Average fresh weight of fruits was not significantly different among supplemental lighting as the harvest date passed. In conclusion, in this study 50% shade treatment significantly improved the growth of cucumber during the summer season. In addition, the growth and fruit characteristics are better than the control without supplemental lighting. This study can be used as basic research data for applying supplemental lighting technology to cucumber cultivation.

Rapid Rural-Urban Migration and the Rural Economy in Korea (한국(韓國)의 급격(急激)한 이촌향도형(離村向都型) 인구이동(人口移動)과 농촌경제(農村經濟))

  • Lee, Bun-song
    • KDI Journal of Economic Policy
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    • v.12 no.3
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    • pp.27-45
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    • 1990
  • Two opposing views prevail regarding the economic impact of rural out-migration on the rural areas of origin. The optimistic neoclassical view argues that rapid rural out-migration is not detrimental to the income and welfare of the rural areas of origin, whereas Lipton (1980) argues the opposite. We developed our own alternative model for rural to urban migration, appropriate for rapidly developing economies such as Korea's. This model, which adopts international trade theories of nontraded goods and Dutch Disease to rural to urban migration issues, argues that rural to urban migration is caused mainly by two factors: first, the unprofitability of farming, and second, the decrease in demand for rural nontraded goods and the increase in demand for urban nontraded goods. The unprofitability of farming is caused by the increase in rural wages, which is induced by increasing urban wages in booming urban manufacturing sectors, and by the fact that the cost increases in farming cannot be shifted to consumers, because farm prices are fixed worldwide and because the income demand elasticity for farm products is very low. The demand for nontraded goods decreases in rural and increases in urban areas because population density and income in urban areas increase sharply, while those in rural areas decrease sharply, due to rapid rural to urban migration. Given that the market structure for nontraded goods-namely, service sectors including educational and health facilities-is mostly in monopolistically competitive, and that the demand for nontraded goods comes only from local sources, the urban service sector enjoys economies of scale, and can thus offer services at cheaper prices and in greater variety, whereas the rural service sector cannot enjoy the advantages offered by scale economies. Our view concerning the economic impact of rural to urban migration on rural areas of origin agrees with Lipton's pessimistic view that rural out-migration is detrimental to the income and welfare of rural areas. However, our reasons for the reduction of rural income are different from those in Lipton's model. Lipton argued that rural income and welfare deteriorate mainly because of a shortage of human capital, younger workers and talent resulting from selective rural out-migration. Instead, we believe that rural income declines, first, because a rapid rural-urban migration creates a further shortage of farm labor supplies and increases rural wages, and thus reduces further the profitability of farming and, second, because a rapid rural-urban migration causes a further decline of the rural service sectors. Empirical tests of our major hypotheses using Korean census data from 1966, 1970, 1975, 1980 and 1985 support our own model much more than the neoclassical or Lipton's models. A kun (county) with a large out-migration had a smaller proportion of younger working aged people in the population, and a smaller proportion of highly educated workers. But the productivity of farm workers, measured in terms of fall crops (rice) purchased by the government per farmer or per hectare of irrigated land, did not decline despite the loss of these youths and of human capital. The kun having had a large out-migration had a larger proportion of the population in the farm sector and a smaller proportion in the service sector. The kun having had a large out-migration also had a lower income measured in terms of the proportion of households receiving welfare payments or the amount of provincial taxes paid per household. The lower incomes of these kuns might explain why the kuns that experienced a large out-migration had difficulty in mechanizing farming. Our policy suggestions based on the tests of the currently prevailing hypotheses are as follows: 1) The main cause of farming difficulties is not a lack of human capital, but the in­crease in production costs due to rural wage increases combined with depressed farm output prices. Therefore, a more effective way of helping farm economies is by increasing farm output prices. However, we are not sure whether an increase in farm output prices is desirable in terms of efficiency. 2) It might be worthwhile to attempt to increase the size of farmland holdings per farm household so that the mechanization of farming can be achieved more easily. 3) A kun with large out-migration suffers a deterioration in income and welfare. Therefore, the government should provide a form of subsidization similar to the adjustment assistance provided for international trade. This assistance should not be related to the level of farm output. Otherwise, there is a possibility that we might encourage farm production which would not be profitable in the absence of subsidies. 4) Government intervention in agricultural research and its dissemination, and large-scale social overhead projects in rural areas, carried out by the Korean government, might be desirable from both efficiency and equity points of view. Government interventions in research are justified because of the problems associated with the appropriation of knowledge, and government actions on large-scale projects are justified because they required collective action.

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Study on the Thermal Storage Characteristics of Phase Change Materials for Greenhouse Heating (온실보온(溫室保溫)을 위한 상변화(相變化) 물질(物質)의 축열특성연구(蓄熱特性硏究))

  • Song, Hyun-Kap;Ryou, Young-Sun;Kim, Young-Bok
    • Solar Energy
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    • v.13 no.2_3
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    • pp.65-78
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    • 1993
  • An overdose of fossil fuel for greenhouse heating causes not only the high cost and low quality of agricultural products, but also the environmental pollution of farm village. To solve these problems it is desirable to maximize the solar energy utilization for the heating of greenhouse in winter season. In this study phase change materials were selected to store solar energy concentratively for heating the greenhouse and their characteristics of thermal energy storage were analyzed. The results were summarized as follows. The organic $C_{28}H_{58}$, and the inorganic $CH_3COONa{\cdot}3H_2O\;and\;Na_2SO_4{\cdot}10H_2O$ were selected as low temperature latent heat storage materials. The equation of critical radius was derived to define the generating mechanism of the maximum latent heat of phase change materials. The melting point of $C_{28}H_{58}$ was $62^{\circ}C$, and the latent heat was $50.0{\sim}52.0kcal/kg$. The specific heat of liquid and solid phase was $0.54{\sim}0.69kcal/kg^{\circ}C$ and $0.57{\sim}0.75kcal/kg^{\circ}C$ respectively. The melting point of $CH_3COONa{\cdot}3H_2O$ was $61{\sim}62^{\circ}C$, the latent heat was $64.9{\sim}65.8$ kcal/kg and the specific heat of liquid and solid phase was respectively $0.83kcal/kg^{\circ}C$ and $0.51{\sim}0.52kcal/kg^{\circ}C$. The melting point of $Na_2SO_4{\cdot}10H_2O$ was $30{\sim}30.9^{\circ}C$, the latent heat was 53.0 kcal/kg and the specific heat of liquid and solid phase was respectively $0.78{\sim}0.89kcal/kg^{\circ}C$ and $0.50{\sim}0.7kcal/kg^{\circ}C$ When the urea of 21.85% was added to control the melting point of $Na_2SO_4{\cdot}10H_2O$ and the phase change cycles were repeated from 0 to 600, the melting point was $16.7{\sim}16.0^{\circ}C$ and the latent heat was $36.0{\sim}28.0kcal/kg^{\circ}C$.

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Utilization of cement kiln dust as soil amendment material (토양개량제(土壤改良劑)로의 Cement Kiln Dust 이용(利用)에 관(關)하여)

  • Kim, Tae Soon;Song, Ki Jun;U, Zang Keul;Han, Kang Wan
    • Korean Journal of Soil Science and Fertilizer
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    • v.8 no.2
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    • pp.89-96
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    • 1975
  • The experiment was carried out to investigate the chemical properties of cement kiln dusts, abundantly produced from cement industry as a byproduct, and their effectiveness on rice yield. The field experiment was conducted on the acid paddy soil developed on basalt at Dongsong-Myon, Chulwon-Kun, Gangwon-Do. Two kinds of cement kiln dusts were used ; By Pass (BP) collected from the suspension preheater and Electric Precipitate (EP) from the cottrell electric precipitator. The levels of cement kiln dust applied were 100kg/10a, 200kg/10a and 300kg/10a, and the recommended variety "Nong Back" was adopted for this experiment. The results obtained are summarized as follows ; 1. The component of cement kiln dusts seems to be quite suitable for liming material. BP has 55% alkalinity, 41.7% of soluble calcium, 9.8% of soluble magnesium and 4.5% of water soluble silicate, while EP has 53.5% alkalinity, 41.7% soluble calcium, 8.3% soluble magnesium and 1% water soluble silicate. 2. The relative effectiveness of cement kiln dust in the soil will be superior due to very fine particle size. EP pass through completely 270 mesh screen, and 95% of BP pass through 150 mesh screen, 68% passing 270 mesh. 3. BP application at the rate of 100kg/10a increased 21% of rice yield as compared with control and EP 15%. It was observed that the affected yield components were increased panicle number per hill, grain number per panicle and 1,000 grains weight. 4. The application of optimum amount (100kg/10a) of cement kiln dusts accelerated the uptake of nutrients by rice plant and increased rice yield. However, the excess amounts (200kg/10a, 300kg/10a) of cement kiln dusts retarded the uptake of nutrients from soil.

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Investigation of Hazardous Microorganisms in Baby Leafy Vegetables Collected from a Korean Market and Distribution Company (유통 중인 어린잎채소의 미생물 오염도 조사)

  • Kim, Se-Ri;Chu, Hyeonjin;Yi, Seung-Won;Jang, Youn-Jung;Shim, Won-Bo;Nguyen, Bao Hung;Kim, Won-Il;Kim, Hyun Ju;Ryu, Kyeongyul
    • Journal of Food Hygiene and Safety
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    • v.34 no.6
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    • pp.526-533
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    • 2019
  • The purpose of this study was to investigate hazardous microorganisms in mixed baby leafy vegetables and various baby leafy vegetables used as raw materials for fresh-cut produce in spring and summer. To estimate microbial loads, a total of 298 samples including 181 samples of mixed baby leafy vegetables purchased in a Korean market and 117 samples of various baby leafy vegetables from distribution companies were collected. Fecal indicators (coliform and Escherichia coli) as well as food-borne pathogens (E. coli O157:H7, Salmonella spp., Staphylococcus aureus) were enumerated. As a result, the mixed baby leafy vegetable samples showed significantly higher (P<0.05) coliform bacteria numbers in summer (5.59±1.18 log CFU/g) compared to spring (3.60±2.53 log CFU/g). E. coli was detected in 1.3% (1/79) and 42.2% (43/102) of samples collected in spring and summer, respectively. Only one sample collected from a market in spring was contaminated with S. aureus. In the experiment with baby leafy vegetables, the number of coliforms detected in baby leafy vegetables cultivated in soil in spring was 1.15±1.95 log CFU/g, and that in summer was 4.09±2.52 log CFU/g. However, the number of coliforms recovered from baby leafy vegetables cultivated in media was above 5.0 log CFU/g regardless of season. Occurrences of E. coli were 44.4% (12/27) and 19.0% (4/21) for baby leafy vegetables cultivated in soil and media, respectively. However, E. coli O157:H7 and Salmonella spp. were not detected. These results are in relation to microbial loads on mixed baby leafy vegetables associated with raw materials. Therefore, it is necessary to develop and implement hygienic practices at baby leafy vegetable farms to enhance the safety of fresh produce.

Seeding Rate and Planting Date Effects on Forage Performance and Quality of Spring Oats (연맥의 사초특성 및 품질에 미치는 파종량 및 파종기의 영향)

  • Kim, S.G.;Kim, J.D.;Park, H.S.;Kim, D.A.
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.19 no.3
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    • pp.233-240
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    • 1999
  • Understanding of the relationships between seeding rate and planting date is important for production of spring oats during the fall season. Therefore, this experiment was conducted to investigate seeding rate and planting date effects on forage performance and quality of spring oats(Avena sativa L.) at Suweon in 1997. The experiment was arranged in a split plot design with three replications. The main plots consisted of different seeding rates such as 150, 200, and 250kg/ha. The subplots consisted of different planting dates of spring oats such as 15, 22, and 29 August and 5 September. Dry matter content of oats was significantly decreased(P<0.01) as the planting date was delayed except the planting date of 5 September(24.8%). Dry matter content of forage oats planted on 15, 22, and 29 August was 23.0, 21.5, and 20.5%, respectively. A seeding $rate\;{\times}\;planting$ date interaction for dry matter content was highly significant(P<0.01). Crude protein content of oats was significantly increased(P<0.01) from 15.6 to 27.9% as the planting was delayed, while a significant seeding $rate\;{\times}\;planting$ date interaction for crude protein content of oats was observed. Acid detergent fiber(ADF) and neutral detergent fiber(NDF) contents of oats increased with early planting(P<0.01), but there was no significant difference among the seeding rates. ln vitro dry matter digestibility(IVDMD) of oats was significantly increased(P<0.01) as the seeding rate was increased together with late planting. Average dry matter yield of oats decreased(P<0.01) from 2,647 to 615kg/ha as the planting was delayed, but there was no significant difference among the seeding rates. A seeding $rate\;{\times}\;planting$ date interaction was observed for average dry matter yield of oats that the seeding rate increase in this experiment showed better at early planting dates. Crude protein yield of oats increased from 171 to 410kg/ha as the planting was delayed, and a significant increases(P<0.01) for crude protein yield was found among the seeding rates. ln vitro digestible dry matter(IVDDM) yield of oats decreased(P<0.01) as the planting was delayed, but there was no significant difference among the seeding rates. A significant seeding $rate\;{\times}\;planting$ date interaction for lVDDM of oats was found. The results of this study indicate that both the seeding rate of 200kg/ha and early planting before 29 August would be recommendable for forage yield and quality of oats in Korea.

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