• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.2
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• pp.77-80
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• 2003

This study was conducted to determine the optimum organic fertilizer rate (0, 100, 200, 300, 400, 500, 600kg/10a) of worm casting on growth response and yield of Ieol´ radish in Jeiu island. The results obtained were summarized as follows; plant height was getting bigger as organic fertilizer increased from 0 to 500kg/10a and then became smaller at 600kg/10a. But was no significance from 200 to 600kg/10a. Number of leaves, leaf width and root diameter were the same trend with plant height response. Root length was not significantly affected by organic fertilizers. SPAD reading value of leaves increased as increasing of organic fertilizers. Fresh matter yield (top+root) increased significantly 2,949∼4,561kg/10a as fertilizer rate increased from 0 to 200kg/10a, increased 5.096∼5,707kg/10a from 300 to 500kg/10a of fertilizer rate and decreased to 4,873kg/10a at 600kg/10a. Top and root weight were the same trend with fresh matter yield.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.2
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• pp.208-214
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• 1985

An attempt to evaluate yield response and efficiency of N fertilizer was made with the data obtained from various rice cultivars during 1978 to 1983. 1. The optimum rate of N fertilizer for maximum yield varied from 13.9 to 28.0 kg/10a with rice varieties. 2. The cultivars with high optimum N levels were high in N content (straw) and N uptake (straw+grain) at harvesting stage, but low in production efficiency and use efficiency of N. 3. The yield increment at the optimum rates of N in comparison with no N application among the rice varieties were 29-101%. 4. The cultivars with hish yield increment at optimum rate were high in the N content (straw+grain), and production efficiency at harvesting stage.

• Weed & Turfgrass Science
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• v.1 no.4
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• pp.38-43
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• 2012

This study was conducted to predict the yield response of red pepper and to determine the economic weed threshold levels for red pepper cultivation field from competition with the most serious weeds, Amaranthus patulus and Digitaria ciliaris in Youngyang of Korea. Crop yield as a function of weed density was predicted by using a rectangular hyperbola, and their economic threshold levels were determined by using the equation developed by Cousens (1987). The red pepper yield loss models of weeds were predicted as y=304.7/(1+0.063x), $R^2$=0.967 in D. ciliaris and y=281.3/(1+0.1723x), $R^2$=0.952 in A. patulus. Economic thresholds calculated using Cousens' equation were negatively related with the competitiveness of weed. Economic thresholds of each weed were calculated as 18.2 plant $100m^{-2}$ in D ciliaris, and 7.2 plant $100m^{-2}$ in A. patulus.

• Applied Chemistry for Engineering
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• v.29 no.5
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• pp.503-509
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• 2018

In this study, we used the ultrasonic extraction process as a method to extract antioxidant substances from kudzu, and measured the content of iso-flavonoids puerarin, daidzein, daidzin contained in kudzu. The response surface methodology which is a statistical analysis method for optimizing the extraction amount of iso-flavonoids from the kudzu and the process condition for maximizing the yield was applied. It is the final objective of this study to effectively derive the condition of the process that matches the target response with a minimum number of experiments and analyze the effect of each process condition on the response. In the response surface methodology, the central composite design was applied and the optimum condition was analyzed, and the three independent variables were set to ultrasonic irradiation time, volume ratio of ethanol/ultrapure water, ultrasonic irradiation power. Using the response surface methodology, the optimum conditions with the maximum extraction yield and the content of iso-flavonoids were evaluated as ultrasonic irradiation time (24.75 min), ethanol / ultrapure water volume ratio (39.75 vol%), ultrasonic irradiation power (592.36 W). The overall satisfaction level appears as high as 0.8938, which is recognized at a significance level within 5%. As a result of analyzing the optimization process, it was confirmed that the ultrasonic irradiation time is the factor that most affects the responses.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.1
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• pp.89-94
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• 1997

The present study was conducted to know the growth and yield of in response to the drought stress at the different soybean growth stage. Drought stress was given to the soybean plants on early vegetative growth at fourth-node stage(FNS), mid-growth at beginning pod stage(BPS) and late growth at beginning seed stage(BSS) for 30 days, which are high availability in soil water stress on climate condition of Korea. Dry weight was decreased severely by water stress at FNS, and BPS and BSS has no difference compared to control. Chlorophyll content of leaf severely decreased at the end of water stress of FNS and BPS, but was recovered at the harvest stage. Drought-stressed root distributed mainly near the soil surface and number and dry weight of root nodule were decreased severely by drought stress at BPS. Number of pod, seed weight and yield were decreased by drought stress and showed the highest yield loss at BPS.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.5
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• pp.356-360
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• 2002

The seedlings of yacon (Polymnia sonchifolia Poeppig ＆ Endlicher), which were cuttings, plug seedling (PS), crown bud before sprouting (CBBS), crown bud after sprouting (CBAS), and divided seedling after budding (DSAB) were planted at 70$\times$50 cm planting distance on ridge; that was interow spacingintrarow spacing, and about 28,500$\pm$71 plants/ha. CBBS didn't need work and equipment to raise seedlings. PS and DSAB grew taller to 140.5 and 143.3cm, respectively, than others at 150 days after planting. In the changes of plant height, PS and DSAB showed taller than others during growth period, cuttings, CBBS, and CBAS grew rapidly in middle growth stage. Excepting main stem and petiole length, other characters were significant for seedling. Fresh weights were different among seedlings. Even though the yield of plants grown from CBAS and CBBS were lower with 34.7 and 36.4 ton/ha, respectively, than 3.6 ton/ha of DSAB; its yield index were over 95%, hence, those of plants grown from cutting and PS were lower with 73 and 87%, respectively. The ratio of tuberous roots over 200g to total tuberous roots per plant was the highest from DSAB. Most of tuberous roots were under 200g per tuberous root from cuttings. CBBS, CBAS, and DSAB are suitable to use seedlings for high yield of yacono. Yacon plant by DSAB much produced tuberous root of over 200g.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.4
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• pp.256-261
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• 2005

The experiment was conducted at the Ban­gabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur to study the response of chickpea (Cicer arietinum L) to dual inoculation of Rhizobium and arbuscular mycorrhiza, poultry litter, nitrogen, and phosphorus on spore population and colonization, nodulation, growth, yield attributes, and yield. The performance of Rhizobium inoculant alone was superior to control in all the parameters of the crop studied. Among the treatments dual inoculation of Rhizobium and arbuscular mycorrhiza in presence of poultry litter performed best in recording number and dry weight of nodules, dry weight of shoots and roots, number of pods/plant, number of seeds/pod, and seed yields of chickpea. The highest seed yield of 3.96g/plant was obtained by inoculating chickpea plants with dual inoculation of Rhizobium and arbuscular mycorrhiza in association with poultry litter. Treatments receiving dual inoculation of Rhizobium and arbuscular mycorrhiza in presence of nitrogen and phosphorus, Rhizobium inoculant in presence of nitrogen and phosphorus, and that of arbuscular mycorrhiza in presence of nitrogen and phosphorus were similar as that of treatment receiving dual inoculation of Rhizobium and arbuscular mycorrhiza in presence of poultry litter. From the view point of nodulation, growth, yield attributes, and yields of chickpea, dual inoculation of Rhizobium inoculant and arbuscular mycorrhiza along with poultry litter was considered to be the balanced combination of nutrients for achieving the maximum output from cultivation of chickpea in Shallow Red Brown Terrace Soil of Bangladesh.

• Journal of The Korean Society of Grassland and Forage Science
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• v.20 no.4
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• pp.285-294
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• 2000

To investigate the effect of Mycorrhiza (Glomus intradics) and Rhizobium inoculation on the N, P utilization and growth response of Alfalfa (Medicago saliva L.) and Perennial ryegrass (Lolium perenne L.) in mixed sward, four treatments (non-inoculation, Control; Mycorrhiza inoculation: M; Rhizobium inoculation, R and Mycorrhiza and Rhizobium inoculation, M+R) were applied. The associated analyses were canied out on the early vegetative growth stage (DAS 56, 56 days after seeding) and on the early flowering stage (DAS 126). The decreased rate of total N and P content in soil, with advancing plant growth, was relatively higher in the M and M + R treatment than control. The content of availabie phosphorus in soil at DAS 126 increased by about 34 and 38 % in M and M+R treatment compared to control (189.2 mg PzOskg DM), while non-significant changes was observed in R treatment. Total N uptake and P uptake in the control at DAS 126 were 44.71 and 3.52 mglplant in mixed sward, respectively. About 71, 98 and 197 % of increases in total N uptake and 70, 72 and 11 1 % of increases in total P uptake were estimated in M, R and M+R treatment. Comparing to control, total dry matter yield significantly increased by 27, 33 and 53 %, and crude protein yield also by 78, 83 and 204 %, respectively, in M, R and M+R treatment. The present data indicated that mycorrhiza orland rhizobium inoculation improved N, P utilization of both alfalfa and perennial ryegrass plants, and consequently increased total yield (especially by dual inoculation, M+R). (Key words : Alfalfa, Perennial ryegrass, Mycorrhiza, Rhizobium, N and P Utilization, Growth, Yield)

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.8
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• pp.1200-1204
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• 1999

Two experiments were conducted to study the effect of urea treatment of rice and wheat straw on feed intake, dry matter (DM) digestibility and milk yield of lactation buffaloes in their late lactation under farmers' management conditions in the western hills of Nepal during 1995 and 1997. Dry matter intake (DMI) from urea treated rice and wheat straw was not improved significantly (p<0.05) nor the total DMI of the lactating buffaloes was improved significantly. However, feeding urea treated rice straw increased straw DMI by 14.2% and total DMI by 10.63% units over the untreated rice straw. Similarly, the increase in straw and total DMI were 20.18 and 17.40% units over the untreated wheat straw fed animals. Although there was no significant effect of urea treatment of both straw on DM digestibility, it was higher for treated than untreated straw at all locations. An overall increment of 18.1% units for rice straw and 13.3% units for wheat straw was observed. There was a significant effect (p<0.01) of feeding urea treated rice and wheat straw on the milk yield of lactating buffaloes during late lactation under farmers conditions. Post experiment milk yield was also significantly (p<0.05) higher for the animals fed treated straw in both the experiments. Buffalo milk yield was also significantly affected by breed (p<0.01), location (p<0.01) and parity (p<0.01) of the animals. General response of the farmers about the technology and their observed effect on animal performance was also very positive.

• Carbon letters
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• v.28
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• pp.72-80
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• 2018

In this study, an empirical relationship between the energy band gap of multi-walled carbon nanotubes (MWCNTs) and synthesis parameters in a chemical vapor deposition (CVD) reactor using factorial design of experiment was established. A bimetallic (Fe-Ni) catalyst supported on $CaCO_3$ was synthesized via wet impregnation technique and used for MWCNT growth. The effects of synthesis parameters such as temperature, time, acetylene flow rate, and argon carrier gas flow rate on the MWCNTs energy gap, yield, and aspect ratio were investigated. The as-prepared supported bimetallic catalyst and the MWCNTs were characterized for their morphologies, microstructures, elemental composition, thermal profiles and surface areas by high-resolution scanning electron microscope, high resolution transmission electron microscope, energy dispersive X-ray spectroscopy, thermal gravimetry analysis and Brunauer-Emmett-Teller. A regression model was developed to establish the relationship between band gap energy, MWCNTs yield and aspect ratio. The results revealed that the optimum conditions to obtain high yield and quality MWCNTs of 159.9% were: temperature ($700^{\circ}C$), time (55 min), argon flow rate ($230.37mL\;min^{-1}$) and acetylene flow rate ($150mL\;min^{-1}$) respectively. The developed regression models demonstrated that the estimated values for the three response variables; energy gap, yield and aspect ratio, were 0.246 eV, 557.64 and 0.82. The regression models showed that the energy band gap, yield, and aspect ratio of the MWCNTs were largely influenced by the synthesis parameters and can be controlled in a CVD reactor.