• Journal of Bio-Environment Control
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• v.26 no.3
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• pp.175-180
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• 2017

This study was conducted for the domestic new cultivar to expand cultivation area and sustainable production. The new domestic cultivar, 'Jinok' and control cultivar, 'Campbell Early', had been investigated on vine growth and fruit quality by different cultivating conditions as open field, rain shelter and unheated plastic house. The growth period of 'Jinok' was faster than 'Campbell Early'. The harvesting date of 'Jinok' was on 13th of Aug. faster than 'Campbell Early' which was on 17th of Aug., and it was on 25th and 29th of Aug. for 'Jinok' and 'Campbell Early' on field cultivation, respectively. The growing length and width of new shoots were similar among the cropping systems. In the result of fruit characteristic evaluation, the soluble solids content of the 'Jinok' and 'Campbell Early' cultivating on the unheated plastic house were $15.4^{\circ}Brix$ and $15.9^{\circ}Brix$, respectively. In the open field condition, those were $15.9^{\circ}Brix$ and $15.8^{\circ}Brix$, respectively. The titratable acidity and chromaticity were similar among the treatments. In the appearance of past and disease, Phomopsis blight was occurred on mid of June and in the end of cultivation period on about early Aug., the damage by Phomopsis blight was the lowest about 14% in the unheated plastic house cultivation on the 'Jinok' cultivar and it was 39% in the open field condition. However, in the open filed cultivation for 'Campbell Early', Phomopsis blight was highly occurred about 49%. During this period, or the end of cultivation, it is necessary for the intensive control.

• Korean Journal of Food Science and Technology
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• v.46 no.6
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• pp.750-756
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• 2014

This study was performed to understand the effect of cultivation periods on the physicochemical characteristics of the starch of five sweetpotato cultivars, cultivated in Muan, Korea. Starch, protein, and ash contents increased with increased cultivation period, whereas amylose content decreased. Rapid viscosity analysis showed that the pasting temperature, peak viscosity, breakdown, setback and final viscosity increased with increased cultivation period. However, trough and final viscosity decreased. Although the onset temperature and peak temperature values increased, the conclusion temperature did not show any consistent patterns by differential scanning calorimetry. X-ray diffraction showed that the starch samples had C-type crystallinity irrespective of the cultivation period and cultivar. The starch granules were dominantly round and oval, or polygonal irrespective the cultivation period. The bigger the particle size was, the longer the cultivation period was.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.2
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• pp.119-123
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• 2010

This experiment was conducted at Sinheung series (fine loamy, mixed, nonacid, mesic family of Fluvaquentic Endoaquepts) in 2007 to 2008 at the National Institute of Crop Science (NICS), RDA, Suwon, Gyeonggi province, Korea. Three kinds of green manure crops (hairy vetch, barley, rye) incorporated in soil for rice cultivation. 6.3 kg N $10a^{-1}$, and3.2 kg $P_2O_5$ $10a^{-1}$ were applied to rye and barley plot before rice transplanting. Chemical fertilizers had not been applied to hairy vetch plot. Glomalin concentration, soil bulk density, and porosity were measured in soil from different green manure crops incorporation after rice harvesting in paddy. Soil bulk density and porosity after rice harvesting improved at surface soil of hairy vetch incorporation plot. Degree of water stable aggregates increased all green manure incorporation plots. Glomalin concentrations significantly increased at hairy vetch incorporation treatment. In barley plot, the concentration of glomalin increased at 10-20 soil depth. There were no differences relationship between soil carbon, and glomalin concentration, but relationship between soil aggregate stability, and glomalin concentration significantly positive under green manure crop-rice cropping system. Rice yield decreased at hairy vetch incorporation plot because of field lodging. We suggested that hairy vetch incorporation should be considered about application amount, and water management using rice cultivation because of soil properties changes.

• The Korean Journal of Pesticide Science
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• v.5 no.4
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• pp.40-44
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• 2001

Pesticide actual usage in fruit crop cultivation was surveyed, and usage trends of individual pesticides were evaluated to provide data for the development of indicators of environmental impact. The amount of pesticide used for fruit crops indicated the order of fungicide>insecticide>herbicide unlike the case of paddy rice. The fungicide rate of total usage was 72% in apple cultivation. Top ranking fungicides used on fruits were Mancozeb, Propineb, Thiophanate-methyl and the main insecticides were Mancozeb, Propineb, Thiophanate-methyl. The usuage by formulation types showed the order of WP>EC>SL>SC>SP>WG. Pesticide usage (a.i.) per hectare by different fruits was citrus 48.6kg, apple 27.1kg, pear 18.6kg, persimmon 17.5kg, peach 11.3kg and grape 9.2kg. Comparison of pesticide usage (a.i.,kg/ha) in some fruit crops between Korea and USA indicated that more pesticides were used for citrus, pear and peach in USA than Korea while more pesticides were used in Korea than USA for apple.

• Korean Journal of Plant Resources
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• v.34 no.4
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• pp.257-262
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• 2021

This study was conducted to investigate the yield loss of soybean by initial density of Heterodera glycines in soil. A soybean cultivar named 'Cheongja5ho' was cultivated as test material in Dangjin city, Chungcheongnam-do, Korea. Each seed was planted with distance of 25 cm in 35 plots by initial density of egg of the cyst nematode on June 21^st, and allowed to harvest on November 12^st in 2019. As a results, the yield of soybean decreased sharply when as the initial density of eggs of cyst nematode increased. The initial density of eggs in soil affected largely on the decreased yields of the soybean by more than 20% in above 2,000 eggs, and 30% in above 6,000 eggs of the cyst. Beyond the 6,000 eggs, the yield loss was more slowly decreased compared with the above cases. Eggs of H. glycines are widely distributed in Korea, resulting in the serious soybean yield loss by H. glycines.

• Korean Journal of Environmental Agriculture
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• v.27 no.3
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• pp.260-266
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• 2008

The aim of present work was to assess the response of soil microbial activity and diversity to green manures under the organically managed grape-greenhouse in early spring. Hairy vetch, milk vetch, and red clover were seeded in fall, and enzymatic activities by dehydrogenase and fluorescein diacetate (FDA) hydrolase, and microbial diversities by Biolog $EcoPlate^{TM}$ and phospholipid fatty acid (PLFA) were characterized for soils sampled in early spring. Dehydrogenase activity and FDA hydrolytic activity did not differentiate the green manures but the average well color development of Biolog EcoPlate was higher in soils covered with red clover than control soil. Soil microbial functional diversity by Biolog EcoPlate differentiated the soils covered with hairy vetch and milk vetch, and Shannon diversity index by Biolog EcoPlate was higher in soils covered with hairy vetch than control soil. Principal component analysis of PLFA differentiated the soils covered with milk vetch from control soil.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.5
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• pp.760-763
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• 2012

This study was conducted to investigate foliar treatment effects of organic agricultural materials for the environmentally-friendly cultivation of grape. The organic materials applied were chitosan, wood vinegar (pyroligneous acid), amino acid solution, and ginkgo leaf extract. All the organic materials were relatively strong acidic ranging lower than pH 4.6. when comparing with other organic materials, amino acid solution contained relatively high contents of selected plant nutrients, such as N, P, K, Ca, Mg, Cu, Fe, Mn, and Zn. As comparison of selected soil properties in the grape cultivating field, soil pH values were lower at the harvest stage than at the first stage of grape growing (before treating the organic materials), and electrical conductivity (EC) and soil organic matter content were higher at the harvest stage in the all plots. The concentrations of available phosphorus increased in most of the plot soils except in control plot (conventional treatment). The concentrations of exchangeable K decreased in the plot treated with ginkgo leaf extract and the control plot. The exchangeable Mg concentrations decreased in soils of all the plots. On the other hand, the concentrations of N and K in the grape leaves were higher with the treatments of chitosan and amino acid solution, P concentrations were higher with the applications of chitosan, wood vinegar and amino acid solution, and Ca and Mg concentrations were higher with chitosan and amino acid solution treatments, respectively, than with others. The yields of grape were higher, $1,581{\sim}1,583kg\;10a^{-1}$, in the control and wood vinegar treatment plots than others. Sugar contents of grape were not different among all the plots.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.2
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• pp.168-177
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• 1997

This study was carried out to find the physico-chemical properties of soils and the rice growth at the pilot project rice farm of Buchanan city, Liberia. The results were as follows. Soils were classified as Plinthic Ferralsols. Real tropical soils had an oxic B horizon of 30cm thick with diffused horizon boundaries. The surface soils have Ochric A horizon with low organic matter. Plinthite was distributed throughout the whole soil profile unevenly. Exposed to sun light, Plinthite was dried out, hardened, and developed irreversibly into ironstone. There were 286 termite hills in 20ha in the project area. The pH value of the termite hills was higher than that of the ordinary soil two units. Soils of the termite hills had higher contents of carbon, nitrogen, available phosphate and exchangeable bases, especially calcium(2,000mg/kg). Available Fe contents was 230~330mg/kg in the surface soil, and 2,200mg/kg in the subsoil. This caused bronzing of rice in a few days after transplanting. The tolerance of Fe toxicity was lower in Korean cultivars than in Liberian cultivars. The tolerant cultivar was Hangang among Korean cultivars and Nizersail and Suakoko 8 among Liberian cultivars. Area weighted average percolation rate was 8.3mm/day and infiltration rate was 2~2.5mm/hr.

• Korean Journal of Food Science and Technology
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• v.44 no.3
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• pp.280-286
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• 2012

The aim of this study was to describe the effects of genetic factors on the chemical composition or metabolites of grapes harvested within the same region. Grapes were separated into pulp, skin, and seed, and physicochemical characteristics were compared among seven grape varieties. The sugar concentrations of the grape musts ranged from $15.17-20.93^{\circ}Bx$ with Seibel variety being highest at $20.93^{\circ}Bx$. pH ranges of grape musts were 3.46-4.02 and total acidity was highest with 1.05 in Steuben variety. Tartaric acid content was highest with 146.68, 500.10 mg/L in pulp and skin extract of Merlot variety. Malic acid content was highest in pulp extract of Seibel variety (1127.14 mg/L) and skin extract of Chardonnay variety (1720.06 mg/L). K content was highest with 379.13 and 828.01 mg/L in pulp and skin extract of Chardonnay variety. Ca content was highest in pulp extract of Kyoho variety (6.98 mg/L) and skin extract of Campbell Early variety (12.26 mg/L).

• Korean Journal of Food Science and Technology
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• v.52 no.3
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• pp.284-289
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• 2020

The cultivars of wine grapes 'Doonuri', 'Narsha', 'Cabernet Sauvignon', and 'Merlot' were cultivated in Modified-T (MT), Modified-T Cane pruning (MTC), and Geneva Double Curtain (GDC) trellises, and the changes in vine growth, fruit and wine characteristics were compared for two years (2018 and 2019). With respect to the vine growth characteristics, the wine grape cultivars cultivated in the GDC trellis were significantly inferior to those cultivated in the MT or MTC trellises. The grape yields of the cultivars cultivated in GDC trellise increased by 1.5 to 2 times cultivated in the GDC trellises compared to those cultivated in the other trellis, however, the fruit characteristics (total soluble solids, titratable acidity, and berry weight) did not differ among the differently cultivated groups. Moreover, the anthocyanin content and red color of the wine were significantly enriched in all red wine grape cultivars cultivated in the GDC trellises.