• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.1
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• pp.43-49
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• 2013

This work was conducted to obtain some information about stable production of high quality seed-tubers in the late season cultivation of virus-free sweet potato [Ipomoea batatas (L.) Lam.]. Growth characteristics and storage root yield between virus-free and farmer's slips in 9 cultivars were investigated using black-film vinyl mulching cultivation with $75{\times}25cm$ planting density on July 10. At 30 days after planting, vine length, vine diameter, number of node, and number of branch in virus-free slips were significantly increased than those in farmer's slips. The vine growth was significantly different among cultivars, and vine elongation was excellent in 'Kogeonmi', 'Shincheonmi', 'Shinhwangmi', 'Shinyulmi', and 'Yeonhwangmi' compared to the other cultivars. At 110 days after planting, vine length, vine diameter, number of node, number of branch, and fresh weight were significantly different among cultivars, but no significant differences between virus-free and farmer's slips were seen except number of node. Total yield in virus-free slips was increased by 12-49% among cultivars than that in farmer's slips. The mean yields between virus-free and farmer's slips were 1,625 kg/10a and 1,230 kg/10a, respectively, and it was significantly different between virus-free and farmer's slips. Percentage of marketable storage root in virus-free slips was 65.6%, and it was significantly higher than 57.8% in farmer's slips. Marketable yields ($40g{\leq}$) between virus-free and farmer's slips were 1,067 kg/10a and 710 kg/10a, respectively. Marketable yield in 'Shincheonmi', 'Shinyulmi' and 'Shinzami' was more than 1,300 kg/10a, and these cultivars showed to be highly adaptable for the late-season cultivation among 9 tested cultivars.

• Journal of The Korean Society of Grassland and Forage Science
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• v.12 no.3
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• pp.193-200
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• 1992

This study was carried out to determine the optimum fertilizer level of phosphate for maximum yield of soiling cowpea(Vigna sinensis Endlicher) in Cheju. The results obtained are summarized as follows:1. Plant length, fresh yield, stem and leaf weight per plant, node number of main stem, primary branch number per plant, pod number per plant and pod weight per plant increased with increasing of phosphate level regardless of growth stage.2. Plant length and node number of main stem did not increase after August 25, 40 days after planting. Leaf weight and fresh yield were greatest on August 25, and then reduced. 3. Stem weight the number of leaves and pods and pod weight per plant increased until September 13, 80 days after planting. 4. Increased level of phosphate delayed leaf weight decrease after August 25. 5. Root length and root weight per plant increased with increasing level of phosphate regardless of growth stage, and they did not increase after Augest 25. 6. Nodule number and nodule weight per plant also increased as phosphate rate increased regardlessof growth stage. Nodule number and nodule weight were greatest on August 5, and then rapidly decreased.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.4
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• pp.367-372
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• 2017

This work was conducted to identify sweet potato [(Ipomoea batatas (L.) Lam.)] cultivars showing high yield and processing suitability in the Jeonbuk region of Korea. Shoot-slips (30 cm in length) of 14 cultivars were planted with a planting density of $75{\times}25cm$ on May 30, and cultivated with black film mulching. Vine elongation at 30 days after planting was significantly increased (> 90 cm) in 'Dahomi' and 'Sinhwangmi', and was excellent (> 250 cm) 120 days after planting in 'Sinhwangmi', 'Shinyulmi', 'Daeyumi', 'Jinhongmi', and 'Yeonhwangmi'. The branch number per plant showed a dramatic increase in 'Shinzami' 30 and 120 days after planting. The leaf number per plant showed the highest increase in 'Shinzami' 30 days and in 'Sinhwangmi' 120 days after planting. Total weight, mean weight, and number of marketable tubers per plant were significantly higher 150 days after planting than that 120 days after planting. Marketable tuber yield at 120 days was high, over 2.5 ton/10a in 'Daeyumi', 'Dahomi', and 'Jeonmi', and was considerably increased, from 3.2 ton/10a to 3.5 ton/10a, 150 days after planting. Total weight of marketable tubers per plant and marketable tuber yield 120 and 150 days after planting had significant positive correlations with vine length and number of nodes 30 days after planting. Starch value was significantly higher 150 days after planting than that 120 days after planting. 'Daeyumi' and 'Jeonmi' had good growth vigor, high yield, and high starch content; 'Dahomi' also exhibited beneficial traits such as good growth vigor, high yield, and bright orange-colored flesh.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.12
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• pp.3991-4002
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• 1996

Thermally fully developed and thermally developing laminar flows of a Bingham plastic in a circular pipe have been studied analytically. For thermally fully developed flow, the Nusselt numbers and temperature profiles are presented in terms of the yield stress and Peclet number, proposing a correlation formula between the Nusselt number and the Peclet number. The solution to the Graetz problem has been obtained by using the method of separation of variables, where the resulting eigenvalue problem is solved approximately by using the method of weighted residuals. The effects of the yield stress, Peclet and Brinkman numbers on the Nusselt number are discussed.

• Water for future
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• v.10 no.2
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• pp.81-90
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• 1977

The research is conducted to study the effect of the soil physical properties in the direct sowing culture on the water requirement, growth, and yield of rice with Early-Tongil at the experimental paddy field of the Sangju agri. and seri. junior college in Keyngbuk province from 6th May to 15th September in 1977. The experimental plots are designed with the four plots which are non-irrigated standard (plowing to 15cm), non-irrigated deep lowed (plowing to 25cm), irrigated standard (plowing to 15cm), and irrigated deep plowing plot (plowing to 25cm) and also each plot is repreated four times by the split plot design. The results obtained are summarized as follows: 1) The soil sample was ML to 10cm depth from ground surface and those from 10cm to 20cm depth and from 20cm to 30cm were CL. Each specific gravity was 2. 6, 2. 6 and 2. 7. 2) The weather during culturing period was the sane as the normal year of mean temperature. The precipitation was little and the distribution of it was disordered comparing to normal year but the heavy sunshine gave good effect on ripening. 3) Percolation loss was increased more at the non-irrigated plot than at the irrigated plot, and that of deep-plowed plot was increased more. 4) Grain yield per 10a. of non-irrigated deep plowed plot was 898kg, it was greated than others but there wa no significance. 5) A significant difference in the number of spikelets per panicle was found between nonirrigated plot and irrigated plot, and the number of spiklelets per panicle at the nonirrigated plot was more than that of the irrigated plot. But there was no significance in the other yield components-number of panicle, fertility abd ripening ratio-at the irrigated plot, ut weight of 100 grains was higher at non-irrigated plot. 6) Yield and growth at the deep plowed plot were higher than those of standard plowed plot.

• 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.

• Korean Journal of Medicinal Crop Science
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• v.7 no.2
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• pp.89-93
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• 1999

This study was carried out to investigate the effects of planting density, time and frequency of pinching on growth and yield of Lycium chinese Miller cultivated in vinyl house. This experiment was conducted at the experimental field of Cheong-yang Agriculture High School, Cheong-yang, Chung-nam province, in 1997 to 1998. The number of flowers, fruit setting number and dry weight of fruits per branch were increased as the spacings were wider, but the fruit yield per unit area was decreased up to the narrowest spacing plot of $60\;{\times}\;20cm$. The good results of growth status and fruit yield was obtained at the early pinching in May 5. As the more frequent pinching were treated, the more number of flowers and fruits per branch were produced, showing increase of fresh and dry yield, because of much more branches per plot.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.309-309
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• 2017

The experiments were carried out in open experimental field of Field Crops Research Institute, Hai Duong, Vietnam in Winter Spring seasons 2015-2016 and 2016-2017 for finding high yielding of Korean chipping potato varieties which are adaptable to Vietnam condition. Six varieties of Korean potato (G1, G2, G4, G10, B1, B2) were experimented. The control variety (G6) was Atlantic which has long been a standard chip variety. The results showed that, for a hill, there was positive correlation between number of stems and number of tubers. The hill yield also showed highly relation to the plant height and number of tubers. Even though the growth and yield of potatoes grown in the season 2016-2017 were significant higher than these of potatoes grown in the season 2015-2016, their percentages of tubers infected by scab disease were much higher. This is probably because of irregular soil moisture content at the tuber forming duration. While G1, G6 and B1 are white flesh varieties, the remaining are yellow flesh varieties. There are two shapes types among experimented varieties: oblong (G1, G10, B1) and round shape (G2, G4, G6, B2). The total yields of varieties G1, G2, B1, B2 were higher than the total yield of the control variety from 16.5-49.4% in the season 2015-2016 and from 39.8-75.6% in the season 2016-2017.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.3
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• pp.213-219
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• 2013

A field study was conducted to understand nitrogen use efficiency of high yielding Japonica rice varieties under three levels of nitrogen fertilizer (90, 150 and 210 kg N $ha^{-1}$) in Iksan, Korea. Two high yielding rice varieties, Boramchan and Deuraechan, and an control variety, Dongjin2, were grown in fine silty paddy. Nitrogen use efficiencies (NUE) were 83.3, 56.3, and 41.2 in 90, 150, and 210 kg N $ha^{-1}$ fertilizer level, respectively. Total nitrogen uptake varied significantly among nitrogen levels and varieties. Variety Dongjin2 showed the highest nitrogen uptake efficiency (NUpE), while Boramchan and Deuraechan showed higher nitrogen utilization efficiency (NUtE). However, Nitrogen harvest index (NHI) was higher in Boramchan (0.58) than Deuraechan (0.57) and Dongjin2 (0.53). Rough rice yield showed linear relationship with total nitrogen uptake ($R^2$=0.72) within the range of nitrogen treatments. Boramchan produced significantly higher rough rice yield (8546 kg $ha^{-1}$) which mainly due to higher number of panicles per $m^2$ compared to Deuraechan (7714 kg $ha^{-1}$). Deuraechan showed higher number of spikelets per panicle, but showed lower yield due to lower number of panicle per $m^2$. Rice varieties showed different nitrogen uptake ability and NUE at different nitrogen level. Plant breeders and agronomist should take advantage of the significant variations and relationships among grain yield, NUpE, and NUE.

• Mycobiology
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• v.41 no.1
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• pp.47-55
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• 2013

Rhizoctonia solani, Fusarium solani, F. oxysporum, and Macrophomina phaseolina were found to be associated with root rott and wilt symptoms of faba bean plants collected from different fieldes in New Valley governorate, Egypt. All the obtained isolates were able to attack faba bean plants (cv. Giza 40) causing damping-off and root rot/wilt diseases. R. solani isolates 2 and 5, F. solani isolate 8, F. oxysporum isolate 12 and M. phaseolina isolate 14 were the more virulent ones in the pathogenicity tests. Biocontrol agents (Trichoderma viride and Bacillus megaterium) and chemical inducers (salicylic acid [SA] and hydrogen peroxide) individually or in combination were examined for biological control of damping-off and root rot/wilt and growth promoting of faba bean plants in vitro and in vivo. Both antagonistic biocontrol agents and chemical inducers either individually or in combination inhibited growth of the tested pathogenic fungi. Biocontrol agents combined with chemical inducers recorded the highest inhibited growth especially in case SA + T. viride and SA + B. megaterium. Under green house and field conditions, all treatments significantly reduced damping-off and root rot/wilt severity and increased of survival plants. Also, these treatments increased fresh and weights of the survival plants in pots compared with control. The combination between biocontrol agents and chemical inducers were more effective than used of them individually and SA + T. viride was the best treatment in this respect. Also, under field conditions, all these treatments significantly increased growth parameters (plant height and number of branches per plant) and yield components (number of pods per plant and number of seeds per plant, weight of 100 seeds and total yield per feddan) and protein content in both seasons (2010~2011 and 2011~2012). Faba bean seeds soaked in SA + T. viride and SA + B. megaterium were recorded the highest growth parameters and yield components. Generally, the combination between biocontrol agents and chemical inducers recorded the best results for controlling damping-off and root rot/wilt diseases in greenhouse and field with addition improved plant growth and increased yield components in field.