• 한국작물학회지
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• 제44권3호
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• pp.186-190
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• 1999

The objective of this study was to ,determine trinexapac-ethyl [4-(cyclopropyl- $\alpha$ -hydroxy-me-thylene)-3,5-dioxocyclohexanecarboxylic acid ethyl ester] effects on lodging-related traits of rice varieties treated at different application rates and times. Trinexapac-ethyl WP was applied at the rate of 10, 20 and 30g ai/l0a to Heukjinjubyeo and Daeanbyeo, respectively. Effects of trinexapacethyl varied greatly with application time as well as application rate with little differences between rice varieties. As the application rate increased, lodging index, center of gravity and exsertion of panicle above flag leaf decreased, whereas breaking strength and phytotoxicity increased. Exsertion of panicle was greatly influenced by the application time with a little difference by application rate. The most effective application time of trinexapac-ethyl based on lodging index and total internode length (Ist-4th node) was 2DBH(days before heading) in Heukjinjubyeo and 17DBH in Daeanbyeo, resulting in reducing total internode length by 12.9 and 9.7cm, respectively. A significant reduction was found at the 1st, 2nd, and 3rd internodes in Heukjinjubyeo, while at the 2nd and 3rd internodes in Daeanbyeo. No significant difference was found among treatments in the panicle length of both rice varieties but the panicle fresh weights of Daeanbyeo were significantly greater in all trinexapac-ethyl treatments compared with that of the control when measured 20 days after heading. Consequently, trinexapacethyl treatment significantly improved lodging-related traits of rice plants without affecting rice yield and yield components.

• Asian-Australasian Journal of Animal Sciences
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• 제28권8호
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• pp.1116-1122
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• 2015

This study aimed to investigate the effect of sunflower seeds, either as whole or as oil, on rumen fermentation, milk production, milk composition and fatty acids profile in dairy goats. Fifteen lactating Damascus goats were divided randomly into three groups (n = 5) fed a basal diet of concentrate feed mixture and fresh Trifolium alexandrinum at 50:50 on dry matter basis (Control) in addition to 50 g/head/d sunflower seeds whole (SS) or 20 mL/head/d sunflower seeds oil (SO) in a complete randomized design. Milk was sampled every two weeks during 90 days of experimental period for chemical analysis and rumen was sampled at 30, 60, and 90 days of the experiment for ruminal pH, volatile fatty acids (tVFA), and ammonia-N determination. Addition of SO decreased (p = 0.017) ruminal pH, whereas SO and SS increased tVFA (p<0.001) and acetate (p = 0.034) concentrations. Serum glucose increased (p = 0.013) in SO and SS goats vs Control. The SO and SS treated goats had improved milk yield (p = 0.007) and milk fat content (p = 0.002). Moreover, SO increased milk lactose content (p = 0.048) and feed efficiency (p = 0.046) compared to Control. Both of SS and SO increased (p<0.05) milk unsaturated fatty acids content specially conjugated linolenic acid (CLA) vs Control. Addition of SS and SO increased (p = 0. 021) C18:3N3 fatty acid compared to Control diet. Data suggested that addition of either SS or SO to lactating goats ration had beneficial effects on milk yield and milk composition with enhancing milk content of healthy fatty acids (CLA and omega 3), without detrimental effects on animal performance.

• Journal of Ginseng Research
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• 제28권4호
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• pp.207-210
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• 2004

본 시험은 약토 시용량을 절약하기 위하여, 약토 시용량을 기준 70(l/칸)보다 줄이고, 부족분을 추비로서 대체 가능성을 검토하였다. 약토의 시용량을 줄이고 추비를 시용한 처리구(25.5l+SD)는 관행(70l)구보다 근직경, 근생체중 및 식재가능묘삼 생산량이 대등하여, 약토를 절감할 수 있는 시용방법으로 제시되었다. 약토의 시용량을 줄이고 추비를 시용한 처리구(25.5l+SD)는 관행(70l)구보다 묘삼뿌리에서 질소, 인산 및 칼리의 함량이 낮았으나, 칼슘과 마그네슘은 차이가 없었다.

• 한국약용작물학회지
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• 제15권2호
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• pp.138-141
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• 2007

Good quality seedlings produced in the seedbed of Yangjik, traditional seedling cultivation, is one of the most important factors in determining the yield and quality of $4{\sim}6-year-old$ ginseng. This study was carried out to substitute Yacto, traditional organic fertilizer, for economical compost in the cultivation of seedling by fertilizing relatively little amount of compost into seedbed soil. Bulk density and solid phase were decreased in physical properties of seedbed soil, while air phase and porosity were increased by more addition of compost. When the amount of applied compost in seedbed soil was above $8{\ell}$ per Kan, the contents of nutrient were exceeded the range of optimal standard for ginseng cultivation. Chlorophyll content and stem length were increased by more addition of compost, while the length and the width of leaves showed the highest value at the application level of $8{\ell}$ per Kan. Heat injury was also increased distinctly above the application level of $8{\ell}$ per Kan. The number of first grade seedlings and usable seedlings, and fresh root weight per plant showed the peak at application level of $8{\ell}$ per Kan, respectively. Fertilizing the compost of $8{\ell}$ per Kan into seedbed soil was the optimal amount for producing the good quality seedlings.

• 한국약용작물학회지
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• 제20권3호
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• pp.184-189
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• 2012

This study was carried out to have the basic and applied informations relating to increase the productivity and quality of ginseng. 2 years-old ginseng was cultivated under hydroponic culture with the controlled environment conditions in a greenhouse. Major growth characters and yields were investigated with two different temperatures and several growth stages. The plant height and stem diameter were higher at low temperature than those at high temperature. They were not clearly different with six different growth stages. The root length was not clearly different between two temperatures; however it was continuously grown from June until August. The root diameter was higher at low temperature than that at high temperature. It was rapidly increased from June until August. The length, width, and area of leaf were higher at low temperature than those at high temperature. The fresh and dry weights of different plant tissues were also heavier at low temperature than those at high temperature. The moisture content of ginseng root was continuously decreased from June until August. The yield of ginseng was higher at low temperature compared to that at high temperature. The cultivating conditions in hydroponic culture of ginseng, especially temperature, would be an important factor to have better growth and production.

• 한국환경과학회지
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• 제21권12호
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• pp.1435-1447
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• 2012

The present study was conducted to determine the effect of hexaconazole (HEX), a triazole fungicide, on the growth, yield, photosynthetic response and antioxidant potential in cucumber (Cucumis sativus L.) plants subjected to UV-B stress. UV-B radiation and HEX were applied separately or in combination to cucumber seedlings. The growth parameters were significantly reduced under UV-B treatment, however, this growth inhibition was less in HEX treated plants. HEX caused noticeable changes in plant morphology such as reduced shoot length and leaf area, and increased leaf thickness. HEX was quite persistent in inhibiting shoot growth by causing a reduction in shoot fresh and dry weight. HEX noticeably recovered the UV-B induced inhibition of biomass production. Significant accumutation in anthocyanin and flavonoid pigments in the leaves occurred as a result of HEX or UV-B treatments. HEX permitted the survival of more green leaf tissue preventing chlorophyll content reduction and higher quantum yield for photosystemII under UV-B exposure. HEX treatment induced a transient rise in ABA levels in the leaves, and combined application of HEX and UV-B showed a significant enhancement of ABA content which activates $H_2O_2$ generation. UV-B exposure induced accumulation of $H_2O_2$ in the leaves, while HEX prevented UV-B induced increase in $H_2O_2$, indicating that HEX serves as an antioxidant agent able to scavenge $H_2O$ to protect cells from oxidative damage. An increase in the ascorbic acid was observed in the HEX treated cucumber leaves affecting many enzyme activities by removing $H_2O_2$ during photosynthetic processes. The activities of antioxidant enzymes including catalase(CAT), ascorbate peroxidase(APX), superoxide dismutase(SOD) and peroxidase(POD) in the leaves in the presence of HEX under UV-B stress were higher than those under UV-B stress alone. These findings suggest that HEX may participate in the enhanced tolerance to oxidative stress. From these results it can be concluded that HEX moderately ameliolate the effect of UV-B stress in cucumber by improving the components of antioxidant defense system.

• The Plant Pathology Journal
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• 제32권3호
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• pp.216-227
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• 2016

Biological control agents (BCAs) from different microbial taxa are increasingly used to control bacterial wilt caused by Ralstonia solanacearum. However, a quantitative research synthesis has not been conducted on the role of BCAs in disease suppression. Therefore, the present study aimed to meta-analyze the impacts of BCAs on both Ralstonia wilt disease suppression and plant (host) growth promotion. The analysis showed that the extent of disease suppression by BCAs varied widely among studies, with effect size (log response ratio) ranging from -2.84 to 2.13. The disease incidence and severity were significantly decreased on average by 53.7% and 49.3%, respectively. BCAs inoculation also significantly increased fresh and dry weight by 34.4% and 36.1%, respectively on average. Also, BCAs inoculation significantly increased plant yield by 66%. Mean effect sizes for genus Pseudomonas sp. as BCAs were higher than for genus Bacillus spp. Among antagonists tested, P. fluorescens, P. putida, B. cereus, B. subtilis and B. amyloliquefaciens were found to be more effective in general for disease reduction. Across studies, highest disease control was found for P. fluorescens, annual plants, co-inoculation with more than one BCA, soil drench and greenhouse condition were found to be essential in understanding plant responses to R. solanacearum. Our results suggest that more efforts should be devoted to harnessing the potential beneficial effects of these antagonists, not just for plant growth promoting traits but also in mode of applications, BCAs formulations and their field studies should be considered in the future for R. solanacearum wilt disease suppression.

• 한국작물학회지
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• 제49권5호
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• pp.389-393
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• 2004

This study was carried out to investigate the difference of growth characteristics, yield and extract content between upland and paddy ginseng cultured with 4­year-old ginseng in 2003. Although upland ginseng showed larger variation in yield than that of paddy ginseng, the average of it was greater than that of paddy ginseng because it showed better growth of aerial part and higher survival rate than that of paddy ginseng. Moisture content of fresh root was $71.8\%\;(68.5\~73.1\%),\;and\;72.7\%\;(70.2 \~74.9\%)$ on average in upland and paddy ginseng, respectively. Paddy ginseng showed higher hardness in taproot, and higher rate of rusty colored root than that of upland ginseng. The ratio of taproot dry weight in upland ginseng was smaller than that of paddy ginseng, while that of lateral root was larger in upland ginseng. Ratio of marketable root (>60g) to total harvested roots was $13.7\%\;(0.82\~8.0\%)\;and\;7.7\%\;(1.6\~12.6\%)$ in upland and paddy ginseng, respectively. Extract content did not show distinct difference between upland and paddy ginseng, but it showed large variation from $16.1\;to\;25.1\%$ in taproot, and from $24.2\;to\;32.5\%$ in lateral root depanding on the ginseng field examined.

• 한국작물학회지
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• 제47권3호
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• pp.157-160
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• 2002

삼백초의 근경 수확방법을 인력수확에서 생력기계화 수확기술로 개선코자 트랙터부착 굴취기 등 4종의 수확기기의 기계수확 효율을 비교, 검토하였던 바 그 결과를 요약하면 다음과 같다. 1. 총생력시간은 인력에 비하여 경운기 경운 60%, 경운기부착 굴취기 64%, 트랙터부착 굴취기 67%절감되었다. 2. 근경의 손실율은 인력수확 13.9%, 경운기 경운 11.7%, 경운기부착 굴취기 9.8%, 트랙터부착 굴취기 5.1%로 기계수확에서 낮았다. 3. 상품 근경수량은 인력수확 3,032 kg/10a에 비하여 경운기 경운은 248 kg 감소하였으나, 경운기부착 굴취기와 트랙터부착 굴취기는 56kg, 320kg각각 증가되었으며, 총 근경수량은 인력수확에 비하여 기계수확에서 3-10%증가되었는데, 트랙터부착 굴취기는 10%의 증가로 가장 높은 수량을 보였다. 4. 경제성은 인력수확에 비하여 기계수확에서 13-27%높았으며, 트랙터 부착 굴취기는 27%로 가장 높았다. 5. 트랙터부착 굴취기는 생력효율, 상품수량, 총 근경수량 그리고 경제성에서 가장 높거나, 많은 것으로 나타나 적용가능성이 가장 높은 것으로 나타났다.

• 식물병연구
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• 제12권3호
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• pp.294-297
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• 2006

Leafy lettuce(Lactuca sativa L.) is one of the most important vegetable crops in Korea, cultivated throughout the year in greenhouses. During the autumn of 2005, powdery mildew of lettuce that is a new disease caused by Podosphaera fusca occurred in several plantings grown in plastic houses near Suwon in central Korea. Further survey on commercial fields of the plant in central and southern Korea revealed its widespread occurrence and severe losses. Infections occur on upper part of mature leaves often cause leaf distortions, withering, and reduced vigor and growth. Among 184 greenhouses surveyed 121 were infested by the disease and 52 showed over 10% infection rate. Yields were greatly reduced by the disease reaching only 59% compared to healthy plants. About 60% leaves of infected plant were not marketable and fresh weight of the leaves was 73.6% compared to healthy leaves. Total yield of the greenhouses infested by the disease ranged from $100{\sim}140kg$, while it was 260 kg in a non-infested greenhouse at one time harvest. Since the disease represents a threat to safe cultivation of leafy lettuce in Korea, environmentally-friend control strategies should be urgently developed.