• 한국연초학회지
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• 제11권1호
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• pp.27-39
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• 1989

This study was conducted to determine the time and methods of predicting tobacco yield. by analysis of climatic factors in the period of tobacco season during 8 years from 1979 to 1986 at the Daegu district, south eastern part of Korean peninsular. The results obtained are summarised as follows: 1. Climatic factors of each month which have influence on tobacco yield were the amount of rainfall in May and sunshine hours in July. Among climatic factors at tobacco growth stages, the precipitation yield. But these meteorological factors had different effect on variety. 2. Between tobacco yields and climatic factors by even values of each month, tobacco yield was estimated by equations, flue cured tobacco :Y=190.6-5.230X1+ 0.474$\times$2 + 0.142X3(Xl : Minimum temperature of April, X2: Precipitation during May, X3:Sunshine duration on July), air cured tobacco : Y= 195.3-0.447Xl + 0.363$\times$2 + 0.l12$\times$3(Xl :Maximum temperature of May, X2:Precipitation during May. X3: Sunshine duration on July). While between tobacco yield and climatic factors at different growth stage, predicting equation of yield could be derived, flue cured tobacco : Y=205.8+0.510Xl +0.289$\times$2 + 0.305$\times$3 (Xl :Average temperature during the early growth stage, X2 :Precipitation during the early and maximum growth stage, X3 : Sunshine hours during the leaf and tips maturing stage), air cured tobacco Y=194.T-0.498Xl 10.615$\times$2+0.121$\times$3(Xl ;Maximum temperature during the transplanting time, X2 : Precipitation during the maximum growth stage, X3 : Sunshine hours during the leaf and tips maturing stage).

• 한국초지조사료학회지
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• 제32권4호
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• pp.353-360
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• 2012

This study was conducted to evaluate the nutritive value and the quality of ensiled kenaf after fermentation with three cultivars at three different times of harvesting. Experimental plot were allocated with three harvest date (Early;8/3, medium;8/15 and late;8/28) and three cultivars (Tainung-a, Everglade, Whitten). The DM (dry matter) yield increased with maturity in all three cultivars, especially in Whitten which showed the highest yield at each harvest time. The DM content in Whitten at late harvesting time was higher than other treatments (231 g $kg^{-1}$ DM). The CP (crude protein) contents of the kenaf silage of all three cultivars ranged from 151 to 164 g $kg^{-1}$. Highest content of NDF (neutral detergent fiber) was observed in Everglade at medium harvesting date, but the ADF (acid detergent fiber) content was highest in Everglade at early harvesting date (p<0.05). All treatments produced a pH less than 4.0, which is sufficient for stable storage. The pH of Tainung-a was higher than other cultivars at all harvesting times (p<0.05). Whitten showed the higher content of lactic acid (25.8 g $kg^{-1}$ DM) showed at early harvesting date than other cultivars (p<0.05), while the acetic acid content (21.1 g $kg^{-1}$ DM) was higher in Tainung-a at medium harvesting date (p<0.05). No significant difference was observed in ammonia-Nand butyric acid concentrations among all treatments. These results indicate that a kenaf silage could be used as fodder for ruminants. Especially, the Whitten harvested at late growing stage showed promise as a forage silage crop under Koran environments.

• Mycobiology
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• 제45권3호
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• pp.129-138
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• 2017

In this study, we aimed to characterize fungal samples from necrotic lesions on collar regions observed in different sweetpotato growing regions during 2015 and 2016 in Korea. Sclerotia appeared on the root zone soil surface, and white dense mycelia were observed. At the later stages of infection, mother roots quickly rotted, and large areas of the plants were destroyed. The disease occurrence was monitored at 45 and 84 farms, and 11.8% and 6.8% of the land areas were found to be infected in 2015 and 2016, respectively. Fungi were isolated from disease samples, and 36 strains were preserved. Based on the cultural and morphological characteristics of colonies, the isolates resembled the reference strain of Sclerotium rolfsii. Representative strains were identified as S. rolfsii (teleomorph: Athelia rolfsii) based on phylogenetic analysis of the internal transcribed spacer and large subunit genes along with morphological observations. To test the pathogenicity, sweetpotato storage roots were inoculated with different S. rolfsii strains. 'Yulmi' variety displayed the highest disease incidence, whereas 'Pungwonmi' resulted in the least. These findings suggested that morphological characteristics and molecular phylogenetic analysis were useful for identification of S. rolfsii.

• Journal of Plant Biology
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• 제17권1호
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• pp.15-21
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• 1974

The most commonly grown economical and flue-cured tobacco cultivar Yellow Special A was used in pot-culture tests in order to study Ethrel (2-chloroethyl phosponic acid) effects on accelerating maturity of tobacco leaves in relation to the most adequate level of the chemical useful for field growing, nitrogen level in soil for the most pronounced response, and the most suitable spray period during the growth stages of pre-, post- and topping periods. The following conclusions, thus, were obtained from the present studies; 1. 500ppm Ethrel spray was reconfirmed to be adequate in the practical applications, although the extent of yellow-ripening of tobacco leaves was increased as the Ethrel level increased. The highest leevel treated resulted in causing chemically damaged lesions on leaves and early defoliation. 2. Ethrel-treated leaves showed deeper yellowish tinge to them than those without treatment, while different levels of the chemcial had less influence on the tinge. 3. An adequate level of nitrogen supply to plants favored the Ethrel response, whereas either very low or high level of nitrogen in the soil lowered the chemical effect on accelerating the yellow-ripening. When carbohydrates versus total nitrogen ratio became relatively high, the condition brought out some outstanding Ethrel effects. 4. Chlorophyll level of leaves increased as soil applications of nitrogen level increased, and that also increased carotenoid level of the tobacco leaves. Ethrel-treated leaves showed deeper orange tinge than those without treatment, while the highest level of nitrogen application showed the deepest orange tinge to tobacco leaves. 5. Pre-topping treatment (12 days before topping and flowering) resulted in almost no Ethrel response, and that treatment right on the day of topping, showed response of yellow-leaf ripening at nearly bottom-half leaves of a tobacco plant. The post-topping treatment (12 days after topping) made plants showing full response of Ethrel from bottom to the top leaves of tobacco plant in accelerating the leaf maturity. 6. The extent of Ethrel responses on accelerating yellow-ripening of tobacco leaves was discussed for the modifying influences brought about by certain environmental factors. Discussions were also made about the possible practical applications (particularly for pre-rice planting) and quality difference that may be caused by such growth environments.

• 기술사
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• 제1권1호
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• pp.18-25
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• 1968

Higher yield in rice paddies is greatly dependent on adequately balanced and timely supply of water. A majority of rice paddy in Korea is generally irrigated by rainfall, but in many cases it has to be supplemented by artificial irrigation for optimum rice culture. Although the water requirement of rice plant is for higher Than that of athec crops, submerged condition of rice paddy is not Necessarily required. The moisture requirement of rice plant varies with its growing stages, and it is possible to increase the irrigation efficiency through reduction of water loss due to percolation in rice paddies. An experimental plots were set up by means of sandomized block design with three duplication; (a) All time submerged, (b) Economically controlled, and (c) Extremely controlled. Three different irrigation periods Were (a) Initial sage, (b) Inter-stage, and (c) Yast stage. The topsoil of the three plots were excavated to the depth of 30 cm and then compacted with clay of 6 cm thickness. There after, they were piled up with the excavated top soils, leveled and cored with clay of 6 cm thickness around footpath in order to prevent leakage. The results obtained from the experiments are as follows, 1. There is no difference among the three experiments plots in terms of physical and chemical conditions, soil properties, and other characteristics. 2. Culm length and ear length are not affected by different irrigation methods. 3. There is no difference in the mature rate and 1, 000 grain weight of rice for the three plots. 4. The control plot which was irrigated every three days shows an increased yield over the all the time submerged plot by 17.8 percent. 5. The clay lined plot whose water holding capacity was held 5 days long, needs only to be irrigated every 7 days. 6. The clay lined plot shows an increased yield over the untreated plot ; over all-the-time submerged plot by 18 percent ; extremely controlled plot by 18 percent, and economically controlled plot by 33 percent. 7. It may be saved in water requirement about one Thirds.

• 한국작물학회지
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• 제40권4호
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• pp.518-524
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• 1995

국산 녹차의 채엽시기 및 제차법에 따라 회분, 조지방 및 무기성분 등 일반성분의 변화를 분석한 본 연구의 결과는 다음과 같았다. 채엽기의 신엽의 엽면적은 다엽(평균 7.23$cm^2$)이 봉산리 다엽(평균 6.93$cm^2$)보다 컸으며 엽면적의 변화폭은 2번 채엽기와 3번 채엽기 사이에 봉산리, 부춘리 각각 2.74$cm^2$에서 7.98$cm^2$, 3.10$cm^2$에서 8.23$cm^2$로 가장 컸다. 건물량은 봉산리 평균 26.3%, 부춘리 평균 26.6%이었으며 채엽기에 따라 일정한 경향은 증감을 보이지 않았다. 녹차의 일반성분 중 수분 및 회분 함량은 봉산리 평균 5.6, 6.1%, 부춘리 평균 6.2, 5.8%이었다. 총당함량 및 조지방은 봉산리 평균 4.6, 2.8%, 부춘리 평균 2.8, 2.2%이었으며 후기채엽기에 다소 높은 양을 보였다. 총질소량 및 수용성 단백질은 봉산리 평균 5.1, 1.08%, 부춘리 평균 5.7, 1.02%이었으며 총질소량은 후기채엽기에 감소하였다. 가용성 고형분은 봉산리 평균 33.1%, 부춘리 평균 35.2%이었으며 봉산리의 경우 후기채엽기에 감소를 보였다. 무기성분은 봉산리 평균 2.557%, 부춘리 평균 2.338%, 비타민 C, 비타민 E 및 비타민 A 함량은 각각 봉산리 평균 413, 71.8mg%, 32.15IU, 부춘리 평균 311, 52.3mg%, 25.68IU이었으며 채엽기에 따라 비타민 C와 비타민 E는 후기채엽기에 증가를 보였다. 재차시 증차법 및 부초법 처리에 의한 다엽의 일반성분의 변화는 가용성 고형분함량은 증차법 평균 0.111%, 부초법 평균 0.086% 증가하였으며 조지방은 증차법 평균 0.125%, 부초법 평균 0.241% 감소하였고, 총질소는 증차법 평균 0.019%, 부초법 평균 0.036%, 수용성 단백질은 증차법 평균 0.125%, 부초법 평균 0.078% 증가를 보였다.

• 대한소아치과학회지
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• 제36권3호
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• pp.433-439
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• 2009

성장 시기가 다른 쥐의 편측 교근에 보툴리눔 A형 독소를 주사하여 하악골 성장에 미치는 영향을 알아보고자 하였다. 각기 다른 주령의 쥐(N=36, 1군: 4주령, 2군: 5주령, 3군: 6주령)를 대상으로 실험을 시행하였으며 각 군은 다시 대조군, 편측주사군, 양측주사군으로 나누어 하악골의 길이를 계측하고 다음과 같은 결과를 얻었다. 1. 1군에서 편측주사군의 주사측과 양측주사군 모두 하악체 길이, 과두 높이가 대조군 보다 낮은 값을 보였다(p<0.05). 2. 2군에서 편측주사군의 주사측과 양측주사군 모두 하악 전방부 높이와 과두높이에서 대조군 보다 낮은 값을 보였다(p<0.05). 3. 3군에서 편측주사군의 주사측과 양측주사군 모두 하악체 길이와 과두 높이, 과두돌기 높이가 대조군 보다 낮은 값을 보였다(p<0.05). 4. 세 군 모두 편측주사군의 양측 비교시 통계적으로 유의한 차이는 없었으나 주사측은 대조측 보다 낮은 계측값을 보이는 경향이 관찰되었다(p>0.05).

• 한국수정란이식학회지
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• 제27권1호
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• pp.29-35
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• 2012

The purpose of this study was to examine the effect of growing stages of the Korean Native Striped Bull (KNSB) on the freezability and fertility of frozen-thawed semen. First, we investigated the total motility (TM) and progressive motility (PM) according to the diluent used for semen freezing. Second, we examined the effect of the age of KNSB on semen volume, TM and PM of fresh and frozen-thawed semen. Third, we examined the effect of frozen semen from the different age of KNSB on the $in-vitro$ fertilization rate, and the artificial insemination pregnancy rate. The diluents used in this experiment were Triladyl$^{(R)}$ and Tris-egg yolk extender (EYE). Semen was collected from 5 KNSB in the growing stage (15 months) and 5 adult KNSB (36 months). When Triladyl or Tris-EYE extender was used for semen freezing, there was no difference of the mean TM and the mean PM. However, the mean TM was significantly higher in Bull No. 1885 than Bull No. 4283 ($p$ <0.05). The mean volume of semen collected from the 15-month-old bulls (2.3 ml) was significantly lower ($p$ <0.05) than that from the 36-month-old bulls (5.0 ml). The mean semen concentration was similar for the 15-month-old ($2.1{\times}10^9$ spermatozoa/ml) and 36-month-old ($1.8{\times}10^9$ spermatozoa/ml) bulls. For the 15-month-old and 36-month-old bulls, the mean TM of fresh semen were 93.7% and 88.3%, respectively, and the mean PM were 97.0% and 88.3%, respectively; the 15-month-old bulls showed a particularly high PM ($p$ <0.05). For the 15-month-old and 36-month-old bulls, the mean TM (56.0% and 58.0%, respectively) and the mean PM (64.0% and 70.7%, respectively) of frozen-thawed semen did not differ. The development rates of embryos after $in-vitro$ fertilization and the pregnancy rate after artificial insemination using frozen-thawed semen did not differ according to the bull's age. In summary, semen volume differed according to the bull's age, but semen concentration and survival rate, the $in-vitro$ fertilization rate, and the pregnancy rate did not differ according to the stripe bull's age. Accordingly, semen from bulls in the growing stage can be collected and frozen for the preservation and multiplication of rare livestock.

• 한국농공학회논문집
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• 제62권6호
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• pp.33-42
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• 2020

Emission factors for ammonia and particulate matters (PMs) from livestock buildings are of increasing importance in view of the environmental protection. While the existing emission factors were determined based on the emission inventory of other countries, in situ measurement of emission factors is required to construct an accurate emission inventory for Korea. This study is to report measurements of ammonia and PMs emissions from mechanically-ventilated pig houses, which are common types of pig barns in Korea. Ventilation rates and concentrations of ammonia and PMs were measured at the ventilation outlets of a weaner unit, a growing pig unit and a fattening pig unit to calculated the emission factors. The PMs emission was characterized with different aerodynamic diameters (PM_2.5, PM₁₀, and total suspended particulates (TSP)). The measured ammonia emission factors for weaners, growing pigs and fattening pigs were 0.225, 0.869 and 1.679 kg animal^-1 yr^-1, respectively, showing linear increase with pigs' age. The PMs emission factors for three growing stages were 0.023, 0.237 and 0.241 kg animal^-1 yr^-1, respectively for TSP, 0.017, 0.072 and 0.223 kg animal^-1 yr^-1, respectively for PM₁₀, and 0.011, 0.016 and 0.151 kg animal^-1 yr^-1, respectively for PM_2.5. PMs emissions were increased with pigs' age due to increasing feed supply and animal movement. The measured emission factors were smaller than those of the existing emission inventory indicating that the existing ones overestimate the emissions from pig buildings and also suggesting that long-term in situ monitoring at various livestock buildings is required to construct the accurate emission inventory.

• 한국작물학회지
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• 제68권2호
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• pp.69-80
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• 2023

본 연구는 기후분포가 다른 3개 그룹 지역(G1, G2, G3)에 겉보리를 파종하고, 월동 전(12월), 월동 후(2월) 및 출수기(4월)에 생육과 수확기(6월)에 수량 차이를 조사하였고, 이들 그룹 지역간 생육과 수량차이와 작물생육기 기상요인과 출수기에 토양화학성과 잎 무기성분과 관련성을 조사하였다. 또한 수확기에는 그룹 지역간에 수확한 겉보리 종자의 일반성분, 무기물 및 아미노산 함량을 조사하였다. 월동 전, 후 분얼수는 G1지역이 G2와 G3지역에 비해 높았다. 그러나 출수기의 분얼수와 지상부 건물중은 G2와 G3 지역이 G1지역에 비해 높았다. 재생기, 유수형성기 및 출수일의 경우 G2 지역은 G1과 G3지역에 비해 다소 늦었다. 그러나 엽록소 함량(SPAD값)은 그룹 간에 차이가 없었다. 수량의 경우 G2지역이 G1과 G3지역에 비해 9~15% 감소하였다. G2지역의 수량 감소는 수수, 영화수 및 등숙율 감소에 기인되는 것으로 판단된다. 또한 G2지역에서 수량이 감소했던 것은 G2지역이 작물 생육기에 최고, 최저 및 일 평균기온이 G1과 G3지역에 비해 낮았기 때문인 것으로 판단된다. 그러나 토양 내 무기성분은 G2지역에서 G1과 G3 지역에 비해 높았다. 식물체의 무기성분 함량은 G1지역에서 G2와 G3 지역에 비해 높은 경향이었다. Cu, K, Mg 및 P와 같은 무기물 함량은 G3 지역에서 그리고 조단백질과 대부분 아미노산은 G2 지역에서 다른 지역에 비해 상대적으로 낮은 경향을 보였다. 따라서 재배한계지 G1지역은 주산지 G3 지역에 비해 겉보리 수량과 일반성분, 아미노산 및 무기물 함량 등에 부정적인 영향없이 안정적으로 재배가 가능한 것으로 판단된다.