• 한국응용곤충학회지
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• 제7권
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• pp.69-75
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• 1969

본 시험은 오이류 덩굴쪼김병균의 병원성을 조사하기 위하여 실시하였으며 공시균 24균주를 오이, 참외, 김치 참외, 멜론, 수박 및 수세미오이에 접종한 결과는 다음과 같다. 1. 수박분리균은 수박가 멜론에 대하여 강한 병원성을 나타냈고 그 중에는 김치참외 흑은 참외에 대해서도 병원성을 나타낸 것이 있었다. 2. 오이분리균은 병원성에 따라 네가지 형으로 나눌 수 있는데 오이에 대해서 강하게 병원성을 나타내면서 참외, 김치참외 및 멜론을 감염하는 것이 있었으며, 오이에 대해서는 병원성이 없거나 아주 약하게 나타난 것이 김치참외에 대해서는 강한 병원성을 나타낸 것이 있었다. 또 참외, 김치참외 및 멜론에 대해서만 강한 병원성을 나타내고 오이에 대해서는 전혀 병원성이 없는것과 오이, 참외, 김치참외, 멜론에 대해서는 강한 병원성을 나타내는 한편 수박에 대해서도 중간정도의 병원성을 나타내는 것이 있었다. 3. 참외 분리균은 병원성에 따라 네 가지 형으로 나눌 수 있는데 참외, 김치참외 및 멜론을 강하게 침해하는 것과 참외, 김치참외, 멜론은 물론 수박에 대해서도 병원성이 있는 것이 있었다. 또 김치참외 및 멜론에 대해서 병원성이 약하게 나타난 것과 멜론에 대해서는 강하게 병원성을 나타내고 수박을 약하게 침해하는 것이 있었다. 4. 오이류 덩굴쪼 병균은 병원성에 따라 수박덩굴 쪼김병균, 오이덩굴쪼김병균 및 멜론덩굴쪼김 병균으로 대별할 수 있었으나 공시돈 오이류 덩굴쪼김병균간의 병원성이나 기생범위가 반드시 일정하기 않기 때문에 몇 개의 form specine로 재정리하고 오이류에서 선발된 몇가지 판별품종에 대한 병원성에 따라 race로 나누어야 할 것이다.

• Animal Bioscience
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• 제35권12호
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• pp.1871-1880
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• 2022

Objective: The primary goal was to identify the effectiveness of chemical or biological additives in delaying the deterioration of early-harvested wilted rye silage after exposure to air. Methods: Rye harvested as a whole plant at the early heading stage was wilted for 24 h. The wilted forage was divided into treatments including sodium diacetate (SDA) at 3 (SDA3) and 6 g/kg (SDA6), Lactobacillus plantarum (LP), L. buchneri (LB), or their equal mixture (LP+LB) at 1×10⁶ colony-forming unit/g fresh matter. Results: After 60 d of conservation in 20-L silos, lactic acid was greater in LP and LP+LB silages than other treatments (102 vs 90.2 g/kg dry matter [DM]). Acetic acid was greatest in SDA6 (32.0 g/kg DM) followed by LB (26.1 g/kg DM) and was lowest in LP treatment (4.73 g/kg DM). Silage pH was lower with microbial inoculation and the lowest and highest values were observed in LP and untreated silages, respectively. After 60 d, neutral detergent fiber concentration was lowest in SDA6 silages, resulting in the greatest in vitro DM digestibility (846 g/kg DM). Aerobic stability was longest in SDA6 (176 h) followed by LB treatment (134 h). Instability after aerobiosis was greatest in LP silages (68 h), about 8 h less than untreated silages. After aerobic exposure, yeast and mold numbers were lowest in SDA6 silages, resulting in DM loss minimization. Exhaustion of acetic acid and lactic acid after aerobic exposure was lowest with SDA6 but greatest with untreated and LP silages. Conclusion: Treatment of early-cut wilted rye forage with SDA at 6 g/kg resulted in silages with higher feeding value and fermentation quality, and substantially delayed deterioration after aerobic exposure, potentially qualifying SDA at this load for promotion of silage quality and delaying aerobic spoilage of early-harvested (low DM) rye forage.

• 원예과학기술지
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• 제28권4호
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• pp.529-534
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• 2010

수박($Citrullus$ $lanatus$ L.)의 시듦증은 생리장해라고 알려져 있다. 품질 및 수량을 저하시키고 큰 경제적 손실을 가져오는 이 증상은 주로 한국의 수박 주산지인 의령이나 함안 지역에서 기온이 높아지는 3월 중순 이후부터 시작하며 해에 따라 발생 양상이 차이가 있다. 수박 생리장해에 대한 많은 연구가 수행되고 있으나 시듦증의 발생 기작에 대한 연구는 미흡한 실정이다. 본 연구는 시듦증 발생 기작을 해명하기 위하여 강제환기 처리를 하였으며 경남 의령군 용덕면에서 2009년 1월-5월까지 수행하였다. 관행처리에 비해 강제환기 처리는 시설내 기온, 엽온 및 근권부의 온도를 각각 약 4.5, 5, $3^{\circ}C$정도 낮게 유지시켰고 포차도 낮게 유지시켰다. 전 생육기간 동안 관행 및 강제환기 처리 모두에서 과실 생육속도가 최대를 보이는 시기가 두 차례 관찰되었고 관행에서 그 속도와 시기가 더 빠른 것으로 관찰되었고, 첫 번째 최대기는 착과 후 12일에(350g/일), 그 두 번째는 착과 후 24일에(350g/일) 관찰되었다. 시듦증은 착과 후 22일에 관행처리 에서만 발생하기 시작하였다. 강제환기 처리에서 과실 생육최대기는 관행처리에서 보다 4일 늦게 관찰되었다(350g/일). 동시에 식물체 생육속도도 강제환기가 관행처리 보다 낮은 것으로 나타났다. 이러한 결과들은 강제환기가 전 생육기간 동안 엽온 및 포차를 낮게 유지함으로써 식물체 및 과실의 생육속도를 조절했다는 것을 보여준다. 따라서 강제환기가 건전한 생육을 유도하고 식물체의 증산을 조절함으로써 엽과 과실간 수분경합을 줄여 시듦증을 방지시킨다는 가설을 제시한다. 금후 직접적이고 정밀한 실험을 통해 강제환기효과에 대한 식물체내의 수분균형의 연구가 기대 된다.

• The Plant Pathology Journal
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• 제23권2호
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• pp.70-75
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• 2007

We conducted an inoculation test using nine open-pollinated families of pine trees to evaluate their susceptibility and mortality in different densities of pine wood nematode. Three-year-old nine open-pollinated pine families were inoculated with Bursaphelenchus xylophilus at levels of 3,000, 5,000, and 7,000 nematodes/seedling in greenhouse. There were no distinct patterns in latent period among three densities of B. xylophilus in all families. Most families showed the first disease symptoms of needle discoloration within 12-15 days after inoculation. However, open-pollinated progenies of Pinus densiflora showed the longest latent period because none of one-year-old needles were wilted until 14 days after inoculation with 5,000 and 7,000 nematodes. One-year-old needles were wilted earlier than current needles in all tested families with all densities of B. xylophilus. Current needles were not wilted until 14 days after inoculation in all seedlings. The mortality of all seedlings rapidly increased from 35 days to 49 days after inoculation, and all died within 80 days except two seedlings. A 3,000 nematodes/100 ${\mu}L$ with sterilized distilled water are enough to screen 3-year-old pine seedlings for resistance to B. xylophilus.

• 한국초지조사료학회지
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• 제11권1호
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• pp.53-59
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• 1991

This experiment was conducted to investigate the effects of propionic acid and wilting on fermentation quality of Italian ryegrass silage. Grass material was wilted for a day before ensiling and propionic acid(0. 0, 0. 2. 0. 5 and 0.8 7~ of fresh matter) was applicated at ensiling time. Chemical composition, fermentation acids, pH, microbial population and distribution of the nitrogen contents were evaluated. The results obtained are summarized as follows: 1. The contents of dry matter and water soluble carbohydrate in the silage were increased by wilting, and crude fibre, NDF and ADF were decreased with increasing propionic acid levels. 2. The pH values of the silage increased by increasing DM content, but decreased with increasing propionic acid levels. Lactic acid content lowed in wilted silage, and acetic acid and butyric acid formation were decreased with increasing propionic acid levels. 3. Total nitrogen content in the silage was i n ~ r e a s e d ( ~ < . 05) by addition of propionic acid and wilting, and was the highest in the prewilting-0.8 Q propionic acid applicated silage. The production of NHBN was decreased with propionic acid and was the lowest in the 0.8 % treated silage. 4. The number of total bacteria and yeasts were estimated $10^6~10^7$, $10^2~10^3$ respectively. Moulds number were decreased with increasing propionic acid levels.

• Asian-Australasian Journal of Animal Sciences
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• 제31권12호
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• pp.1913-1922
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• 2018

Objective: To find out ways of improving fermentation quality of silage, the comparative analysis of fermentation characteristics and in vitro digestibility of tropical grasses silage applied with cellulases produced from Acremonium or Tricoderma species were studied in Thailand. Methods: Fresh and wilted Guinea grass and Napier grass silages were prepared with cellulases from Acremonium (AC) or Trichoderma (TC) at 0.0025%, 0.005%, and 0.01% on a fresh matter (FM), and their fermentation quality, chemical composition and in vitro digestibility were analyzed. Results: All silages of fresh Napier grass were good quality with lower pH, butyric acid, and ammonia nitrogen, but higher lactic acid content than wilted Napier grass and Guinea grass silage. Silages treated with AC 0.01% had the best result in terms of fermentation quality. They also had higher in vitro dry matter digestibility and in vitro organic matter digestibility at 6 and 48 h after incubation than other silages. Silages treated with lower levels at 0.005% or 0.0025% of AC and all levels of TC did not improve silage fermentation. Conclusion: The AC could improve silage fermentation and in vitro degradation of Guinea grass and Napier grass silages, and the suitable addition ration is 0.01% (73.5 U) of FM for tropical silage preparation.

• 한국토양비료학회지
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• 제22권2호
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• pp.122-126
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• 1989

위조증상발생(萎凋症狀發生)에서 볼수 있는 품종간차이(品種間差異)를 근계(根系)의 발달(發達) 및 활력(活力)의 특징(特徵)에서 구명(究明)하기 위(爲)하여 농가포장(農家圃場) 및 시험포장(試驗圃場)에서 실태조사(實態調査), 사경재배(砂耕栽培)에 의(依)한 대조품종(對照品種)의 생육시기별조사등(生育時期別調査等)을 실시(實施)한 결과(結果)를 요약(要約)하면 다음과 같다. 1. 급성위조증상(急性萎凋症狀)이 발생(發生)한 "유신(維新)"은 건전주(健全株)에 비(比)해 피해주(被害株)에서 T/R비율(比率)이 높았다. 2. 급성위조증상(急性萎凋症狀)이 발생(發生)한 "유신(維新)"은 건전주(健全株)에 비(比)해 부위(部位)에 관계(關係)없이 근활력(根活力)이 저하(低下)하였다 "유신(維新)"의 영양생장기(營養生長期)에 있어서의 지상부생육량(地上部生育量)은 타(他) 품종(品種)보다 크나 T/R률(率)은 높아지는 경향(傾向)이며, 생육후기(生育後期)에 있어서의 광합성산물(光合成産物)의 근(根)에의 배분량(配分量)이 상대적(相對的)으로 감소(減少)하는것으로 보아 생식생장기(生殖生長期)에 있어서 근(根)의 활력저하(活力低下)를 초래(招來)하는 요인(要因)이 되는 것으로 추정(推定)된다. 3. 위조증상(萎凋症狀)이 발생(發生)한 "유신(維新)"은 영양생장기(營養生長期)의 근활력(根活力)이 높고, 지상부(地上部)의 생장(生長)도 왕성(旺盛)하나 생식생장기(生殖生長期)에는 타(他) 품종(品種)에 비(比)해 활력(活力)이 현저(顯著)하게 저하(低下)하는 특징(特徵)을 나타내는 것이 명확(明確)하게 밝혀졌다. 4. 급성(急性) 위조증상발생(萎凋症狀發生)이 비교적(比較的) 적었던 "밀양(密陽) 23호(號)"의 근활력(根活力)은 피해주(被害株)와 건전주간(健全株間)에 차이(差異)가 없었으며, 양자(兩者) 공(共)히 후기(後期)까지 비교적(比較的) 높게 유대(維待)되었으며, 근(根)도 굵고 T/R비율(比率)도 낮았다.

• Asian-Australasian Journal of Animal Sciences
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• 제17권4호
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• pp.497-503
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• 2004

The effect of adding carbohydrate-rich feedstuffs to sweet potato leaves (SPL) on silage quality was studied using a total of 180 laboratory silos. Silage quality was assessed by changes of pH, dry matter (DM), crude protein (CP) and ammonia nitrogen ($NH_{3}$-N). Pre-wilted SPL was mixed with cassava root meal (CRM), sweet potato root meal (SPM) or sugar cane molasses (Mo) at levels of 0, 30, 60 and 90 g $kg^{-1}$ (air-dry weight of additives to pre-wilted weight of SPL). Samples for assessing silage quality were collected after mixing the SPL with the additive and thereafter at 7, 14, 28 and 56 days of ensiling. There was a marked decrease in pH after 7 days and the pH remained low and stable until day 56. Addition of 60 and 90 g $kg^{-1}$ resulted in a lower pH (p<0.05) than the other treatments. The DM content of the silage increased (p<0.05) with increasing levels of additive, while there were no differences in DM with time of ensiling. The CP content of the silage decreased (p<0.05) with increasing levels of additive. The CP content did not change up to 28 days, but was lower (p<0.05) after 56 days in all treatments. The $NH_{3}$-N levels were increasing (p<0.05) with time of ensiling, and were lower (p<0.05) with additive levels of 60 g $kg^{-1}$ or higher. Also, the additive source affected the $NH_{3}$-N values, with the lowest values found for Mo. Castrated male pigs (Large White$\times$Mongcai) were used in 4$\times$4 Latin square design to study the total tract digestibility and nitrogen (N) utilisation of diets with inclusion of ensiled SPL. The diets were based on cassava root meal with inclusion of protein from either fish meal (C) or SPL ensiled with CRM (D1), SPL ensiled with SPM (D2) and SPL ensiled with Mo (D3). The digestibility of DM, organic matter (OM) and CP were higher (p<0.05), and the digestibility of crude fibre (CF) was lower (p<0.05), in diet C than in diets D1, D2 and D3. However, there were no differences (p>0.05) in digestibility of dietary components between diets D1, D2 and D3. Also, the excretion of N in faeces was higher (p<0.05) and the N retention was lower (p<0.05) in diets D1, D2 and D3 than in diet C. It can be concluded from the present experiments, that a good quality silage can be produced from pre-wilted SPL by addition of 60 g $kg^{-1}$ of either CRM, SPM or Mo. Diets with inclusion of 450 g ensiled SPL $kg^{-1}$ DM showed a high digestibility of dietary components and thus ensiled SPL should be considered as a potential feed resource for growing pigs.

• Journal of Biosystems Engineering
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• 제41권3호
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• pp.273-280
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• 2016

Purpose: This experiment was conducted to detect water stress in terms of the moisture content of cucumber seedlings under water stress condition using a hyperspectral image acquisition system, linear regression analysis, and partial least square regression (PLSR) to achieve a non-destructive measurement procedure. Methods: Changes in the reflectance spectrum of cucumber seedlings under water stress were measured using hyperspectral imaging techniques. A model for estimating moisture content of cucumber seedlings was constructed through a linear regression analysis that used the moisture content of cucumber seedlings and a normalized difference vegetation index (NDVI). A model using PLSR that used the moisture content of cucumber seedlings and reflectance spectrum was also created. Results: In the early stages of water stress, cucumber seedlings recovered completely when sub-irrigation was applied. However, the seedlings suffering from initial wilting did not recover when more than 42 h passed without irrigation. The reflectance spectrum of seedlings under water stress decreased gradually, but increased when irrigation was provided, except for the seedlings that had permanently wilted. From the results of the linear regression analysis using the NDVI, the model excluding wilted seedlings with less than 20% (n=97) moisture content showed a precision ($R^2$ and $R^2_{\alpha}$) of 0.573 and 0.568, respectively, and accuracy (RE) of 4.138% and 4.138%, which was higher than that for models including all seedlings (n=100). For PLS regression analysis using the reflectance spectrum, both models were found to have strong precision ($R^2$) with a rating of 0.822, but accuracy (RMSE and RE) was higher in the model excluding wilted seedlings as 5.544% and 13.65% respectively. Conclusions: The estimation model of the moisture content of cucumber seedlings showed better results in the PLSR analysis using reflectance spectrum than the linear regression analysis using NDVI.

• Asian-Australasian Journal of Animal Sciences
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• 제5권4호
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• pp.673-679
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• 1992

To investigate the effects of molasses addition at ensiling on nutritional quality of wilted napier grass, chemical quality and nutrient composition of the silages, digestibility and nitrogen retention at feeding trials were analysed using 4 goats in a cross over design. The results are as follows : 1. Molasses addition at ensiling decreased pH value (3.99) and ammonia nitrogen, and increased lactic acid content by 285% compared to non-additive silage (83.5 g/kg dry matter). 2. There were no differences in digestibilities of dry matter, crude protein, neutral detergent fiber, acid detergent fiber, hemicellulose and cellulose between the silage ensiled with molasses (MS silage) and the silage ensiled without molasses (WS silage). Urinary nitrogen excretion, however, significantly (p<0.05) decreased in goats fed the MS silage, and nitrogen retention was positive in goats fed the MS silages, but negative in goats fed the WS silage. 3. Acetic acid concentration in remained fluids in goats fed the MS silage was lower and propionic and butyric acid concentrations were higher than those in goats fed the WS silage. As water soluble carbohydrate content was higher in the MS silage than in the WS silage, a part of added molasses was still remained in the silage at the feeding trials and could be utilized for energy sources by the goats. Nitrogen may be also effectively utilized in goats fed the MS silage, because the silage were inhibited in proteolysis during ensiling.