• Korean Journal of Plant Resources
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• v.28 no.5
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• pp.641-647
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• 2015

This study was conducted to select native ground cover plants for sod culture in an organic apple orchard by estimating the effect of three native ground cover plants, Glechoma hederacea, Thymus magnus, and Ixeris stolonifera, on the soil coverage, time-periodic weed occurrence, fruit characteristics, and soil chemical properties. The plant height of G. hederace, T. magnus and I. stolonifera were 15.0 ㎝, 13.4 ㎝ and 7.2 ㎝, respectively. The dry weight of G. hederace, T. magnus and I. stolonifera were 463 ㎏/10a, 247 ㎏/10a, and 255 ㎏/10a, respectively. The plant height and dry weight of G. hederacea were higher than in the other species. T. magnus and I. stolonifera having relatively lower soil cover rate during their life cycle produced a lot of weeds in the orchard as compared with the control. In contrast, G. hederacea showed 100 percentage of ground cover in the first year, and maintained high percentage of ground cover in the growing season of ‘Tsugaru’ apple for another 2 years. When the soil was covered with G. hederacea in the orchard for 3 years, the amount of weed was only 114 ㎏/10a and number of weeding was also reduced about 33% compared with control as well as the other species. There were no differences in the tree growth and fruit characteristics between the native ground cover plants and the control; however, positive effects of native ground cover plants on soil chemical properties were found. In G. hederacea, available P₂O₄content in soils remarkably increased and was a significant difference among native species. In addition, cation (Ca, Mg and K) content in soils increased by 39% in Ca, 6% in Mg, and 11% in K at G. hederacea compared with control. These results suggest that G. hederacea could be advantageous in terms of reducing the amount of herbicide applied and the labor required for weed control, and controlling soil chemical properties; therefore, it is a good candidate for sod culture in an organic apple orchard.

• International Journal of Industrial Entomology and Biomaterials
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• v.45 no.1
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• pp.35-41
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• 2022

Mulberry is a hardy, perennial, deep-rooted plant capable of thriving under diverse agroclimatic conditions. The selection of suitable land and appropriate variety can help the sustainable mulberry field. However, no conclusive and comprehensive investigation has been conducted on the mulberry soil properties and nutritional composition of mulberry cultivars from Korea local areas in previous studies. In our study, soil properties and mulberry leaf components of Korea local mulberry farms were briefly investigated. In result, the soil organic matter (OM) content was significantly high in Buan (6.81%) and Jangseong (6.14%). In contrast, available phosphate (P₂O₅) was different in each local area. To investigate relationship between soil property and nutritive component of mulberry leaf, Cheongil leaf samples from 8 local areas were analyzed. Among the macrominerals (K⁺, Ca²⁺, Na⁺, and Mg²⁺), the concentration of K varied from (1884±9.36) mg/100 g to (2685±11.5) mg/100 g. The potassium (K⁺) of Cheongil leaf in Sangju was the highest at 2685 mg/100 g. Besides macrominerals, flavonoids, total dietary fiber contents and moisture of Cheongil leaf samples were studied in the 8 local areas. In terms of these contents, the variation was largely depending on the local areas. This study provides a possible industrial use of mulberry, and holds promise to enhance the overall profitability of sericulture.

• Korean Journal of Environmental Agriculture
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• v.21 no.1
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• pp.1-6
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• 2002

To elucidate the effect of soil addition and subsoil plowing on the change of sell chemical properties and the reduction of root-knot nematode, this experiment carried out in continuous cropping field of protected oriental melon (Cucumis melo L.). Soil addition reduced electric conductivity (E. C.) from 4.3 to 1.8 dS/m (58%), available $P_2O_5$ from 406 to 182 mg/kg (55%) and organic matter content from 16 to 11 g/kg (31%). Population densities of root-knot nematode in soil reduced as much as 89%, 84%, and 69% at first year, third years, and of five years later, respectively The effects of subsoil plowing were similar to that of soil addition. E. C. and phosphate were reduced from 4.30 to 1.98 dS/m (54%) and phosphate from 406 to 329 mg/kg (19%), respectively. Population densities of root-knot nematode reduced as much as 71%, 67%, and 42% after 1, 3, and 5 years, respectively Subsoil plowing reduced nematode densities only for three years.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.808-813
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• 2011

This study was conducted to reduce the dependability of farmers on chemical fertilizers for rice cultivation. Soil chemical and biological properties were monitored before experiment and at the time of harvesting. The results showed that EC, available $SiO_2$, and exchangeable $Ca^{2+}$ were decreased at the time of harvesting while pH, OM, and exchangeable $K^+$ and $Mg^{2+}$ were remain unchanged, compared with soil before experiment. Population of aerobic bacteria, Bacillus sp., and fungi were also increased at the time of harvesting in the paddy field, compared with before fertilization, in the treatment of 50% soil-testing fertilizer+ 50% compost. Concentrations of N, P, and K in rice leaves increased with the fertilizers application, maximum increase was recorded in 50% soil-testing fertilizer+ 50% compost. Non-significant difference was observed in the morphological parameters of rice among the treatments. The chlorophyll contents of rice leaf increased in a similar fashion up to 60 days, thereafter, sharp decrease was observed in all the treatments. Maximum yield (per 10a) was recorded in the field treated with 50% soil-testing fertilizer+ 50% compost followed by standard applied fertilizer, 70% soil-testing fertilizer+ 30% compost, soil-testing fertilizer and unfertilized plot. Amylose content showed non-significant difference within the treatments. Protein content increased with the use of fertilizers and best protein content was recorded in the treatment of 50% soil-testing fertilizer+ 50% compost. It was concluded that the amount of the chemical fertilizer used was directly proportional to the protein content of rice grain. However, the palatability of rice grown in unfertilized field was better than the treatments but minimum yield was obtained. Hence, the treatment of 50% soil-testing fertilizer+ 50% compost, was the best among the fertilizer combinations for rice cultivation as supported by the yield, protein and palatability index.

• Korean Journal of Soil Science and Fertilizer
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• v.7 no.1
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• pp.23-27
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• 1974

A pot experiment was carried out to investigate the effect of phosphate application and the adjustment of base saturation rate of soils on the growth of soybean. The soils used were very low in available phosphate (10-20ppm) and low in base saturation rates (less than 40%). Treatment included 2 levels of $P_2O_5$ $(40-80ppm){\times}3$ levels of base saturation rates (check, 60.80%) In adjusting the base saturation rate, the ratio between Ca and Mg was maintained at 65:15. Results are summarised as folloing. (1) The levels of phosphate in the experiment did not bring forth significant difference in the yield of soybean. Both 40 and 80ppm of $P_2O_5$ were seemed to be not enough to bring up the remarkable phosphate effect. (2) The increase in base saturation rate of the soils up to 60% proved to be significant in increasing the yield of soybean. Above that level, however, did not affect the yield. (3) The major factor for the increase of yield, in base saturation rate adjustments was the increased Mg-saturation rates. In the range of 10-15% of Mg-saturation rate of soils, there was a linear positive relationship between the yield of soybean and Mg-saturation rate of soils, while the optimum levels of Ca-saturation rates of soil were found to be 35-55%. (4) It was pointed that there is some possibility of relative in-sufficiency of Mg in Korean cultivated soils and that the continued application of liming materials which do not contain proper amounts of Mg may aggravate these situation.

• Horticultural Science & Technology
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• v.32 no.3
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• pp.400-407
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• 2014

Urban farming supplies emotional stability and fresh vegetables to participating persons, however, no information regarding the biosafety of agricultural products from urban farming is available. Here, we collected 260 samples of Chinese cabbages and lettuce from 4 urban community gardens and 6 roof gardens in Seoul from September through October 2012, and monitored the microbiological and parasitological contamination quantitatively and/or qualitatively. The mean counts of total aerobic bacteria and coliforms were $6.1{\pm}0.8\;log\;CFU{\cdot}g^{-1}$ ( range, $5.4{\pm}0.6{\sim}7.1{\pm}0.8\;log\;CFU{\cdot}g^{-1}$) and $4.0{\pm}0.7\;log\;CFU{\cdot}g^{-1}$ (range, $2.3{\pm}0.6{\sim}6.1{\pm}0.9\;log\;CFU{\cdot}g^{-1}$), respectively. Coliforms were detected on 59.6% among 260 vegetable samples. There were no significant differences in the contamination levels of total aerobic bacteria and coliforms between the Chinese cabbages and lettuce, whereas both levels of vegetables from urban community gardens were higher than those of roof gardens (p > 0.05). Escherichia coli was isolated at 3.1% among whole vegetables, and contamination level was $1.5{\pm}0.2\;log\;CFU{\cdot}g^{-1}$. Among foodborne pathogens, Staphylococcus aureus was detected in 1.5%, however, Salmonella spp., Listeria monocytogenes and E. coli O157:H7 were not detected on any of the vegetable samples. We also found undefined parasite eggs from two samples of Chinese cabbages (0.8% of total vegetables we tested). From these study, we found the presence of microbial contamination of agricultural products from urban farming, thus we need further concern to improve the biosafety during production of agricultural products.

• Korean Journal of Environmental Agriculture
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• v.24 no.4
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• pp.398-403
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• 2005

To establish law-put fertilization technique and increase of fertilization efficiency during cultivation of plastic film mulching for plastic the improvement of soil properties, nutrition efficiency and yield by banded subsoil fertilization (BSF) using band spoty applicator was conducted at radish (Raphanus sativus L.) field in Honan Agricultural Research Institute from 1997 to 1998 for 2 years. These results were as follows. T-N, available $P_2O_5$ exchangeable Ca and K contents of soil were increased those of before experiment especially in BSF treatment. Also, the content of soil $NO_3-N$ was higher in BSF as fertilization amount is increasing than in CF (conventional fertilization). Uptake amounts of nitrogen fertilized were high in BSF during overall the growth period of plant and N utilization was high by $21.9{\sim}30.4%$ in BSF compared to in CF. The rate of fertilizer loss by rainfall was largely reduced, because all fertilizer applied was putted around the root zone. The total yields of fresh radish BSF treatments were more increased $13{\sim}37%$ than that of CF treatment.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.249-253
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• 2013

Background: Malignant mesothelioma (MM) is an aggressive tumor of mesothelial surfaces. Previous studies have observed an association between ABO blood groups and risk of certain malignancies, including pancreatic and gastric cancer; however, no information on any association with MM risk is available. The aim of this study was to investigate possible associations amoong MM clinicopathological features and ABO blood groups and Rh factor. Materials and Methods: In 252 patients with MM, the ABO blood group and Rh factor were examined and compared with the control group of 3,022,883 healthy volunteer blood donors of Turkish Red Crescent between 2004 and 2011. The relationship of blood groups with various clinicopathological features were also evaluated in the patient group. Results: The median age was 55 (range: 27-86) and 61.5% of patients were male. While 82.8% of patients had a history of exposure to asbestos, 60.7% of patients had a smoking history. Epithelioid (65.1%) was the most common histology and 18.7% of patients had mixed histology. Overall, the ABO blood group distribution of the 252 patients with MM was comparable with the general population. The median overall survival (OS) was 14 months (95% confidence interval, 11.3-16.6 months). The median OS for A, B, AB, and O were 11, 15, 16, and 15 months respectively (p=0.396). First line chemotherapy was administered to 118 patients. The median OS of patients on pemetrexed or gemcitabine was longer than patient who was not administered chemotherapy [17 months (95%CI, 11.7-22.2) vs. 9 months (95%CI, 6.9-11.0); p<0.001]. Conclusions: The results of this study suggest that patients with MM can benefit from treatment with pemetrexed or gemcitabine in combination with cisplatin. We did not observe a statistically significant association between ABO blood group and risk of MM.

• Journal of Dental Rehabilitation and Applied Science
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• v.23 no.3
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• pp.249-257
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• 2007

State of problem : The use of zirconium oxide all-ceramic material provides several advantages, including a high flexural strength(>1000MPa) and desirable optical properties, such as shading adaptation to the basic shades and a reduction in the layer thickness. Along with the strength of the materials, the cementation technique is also important to the clinical success of a restoration. Nevertheless, little information is available on the effect of different surface treatments on the bonding of zirconium high-crystalline ceramics and resin luting agents. Purpose : The aim of this study was to test the effects of surface treatments of zirconium on shear bond strengths between bovine teeth and a zirconia ceramic and evaluate differences among cements Material and methods : 54 sound bovine teeth extracted within a 1 months, were used. They were frozen in distilled water. These were rinsed by tap water to confirm that no granulation tissues have left. These were kept refrigerated at $4^{\circ}C$ until tested. Each tooth was placed horizontally at a plastic cylinder (diameter 20mm), and embedded in epoxy resin. Teeth were sectioned with diamond burs to expose dentin and grinded with #600 silicon carbide paper. To make sure there was no enamel left, each was observed under an optical microscope. 54 prefabricated zirconium oxide ceramic copings(Lava, 3M ESPE, USA) were assigned into 3 groups ; control, airborne-abraded with $110{\mu}m$ $Al_2O_3$ and scratched with diamond burs at 4 directions. They were cemented with a seating force of 10 ㎏ per tooth, using resin luting cement(Panavia $F^{(R)}$), resin cement(Superbond $C&B^{(R)}$), and resin modified GI cement(Rely X $Luting^{(R)}$). Those were thermocycled at $5^{\circ}C$ and $55^{\circ}C$ for 5000 cycles with a 30 second dwell time, and then shear bond strength was determined in a universal test machine(Model 4200, Instron Co., Canton, USA). The crosshead speed was 1 mm/min. The result was analyzed with one-way analysis of variance(ANOVA) and the Tukey test at a significance level of P<0.05. Results : Superbond $C&B^{(R)}$ at scratching with diamond burs showed the highest shear bond strength than others (p<.05). For Panavia $F^{(R)}$, groups of scratching and sandblasting showed significantly higher shear bond strength than control group(p<.05). For Rely X $Luting^{(R)}$, only between scratching & control group, significantly different shear bond strength was observed(p<.05). Conclusion : Within the limitation of this study, Superbond $C&B^{(R)}$ showed clinically acceptable shear bond between bovine teeth & zirconia ceramics regardless of surface treatments. For the surface treatment, scratching increased shear bond strength. Increase of shear bond strength by sandblasting with $110{\mu}m$ $Al_2O_3$ was not statistically different.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.1
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• pp.22-30
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• 1999

This experiment was carried out to determine the forage yield and mineral contents of silage corn(Zea mays L.), and N balance, soil chemical characteristics and nitrate-N level in infiltration water by different types and N rates of liquid manure applied. Seven treatments consisting of chemical fertilizer $200kg\;N;ha^{-1}$, liquid cattle manure 200, 320 and $440kg\;N;ha^{-1}$, liquid swine manure 200, 320 and $440kg\;N;ha^{-1}$ were arranged in a randomized complete block design with three replications. The results obtained at National Livestock Research Institute, RDA, in Suweon from May 1997 to Aug. 1997 are summarized as follows : There were no significant differences in percentage of dry matter among the treatments, but significant dry matter yield differences were found (P<0.05), and also the mean dry matter yield of liquid swine manure plot was higher than that of liquid cattle manure plot. Potassium, calcium and magnesium contents of silage corn increased with increasing liquid manure application rates (P<0.05). Nitrate-N content of silage corn in the liquid cattle manure treatments was not influenced by liquid manure application rates, but that in the liquid swine manure treatments increased with increasing the N rates of liquid manure application. pH and contents of exchangeable canons of the soil after experiment were raised by increasing the amount of liquid manure application. Available $P_2O_5$ content in topsoil(0-10cm) was highest as $340mg\;kg^{-1}$ at the plot of liquid swine manure $440kg\;N;ha^{-1}$. Concentration of nitrate-N in infiltration water increased at the plot of liquid swine manure $440kg\;N;ha^{-1}$. Amount of nitrogen balance increased with increasing liquid manure application rates. Based on the results of this experiment, it is suggested that the mean dry matter yield of liquid swine manure plot was higher than that of liquid cattle manure plot, and the amount of nitrogen balance increased with increasing liquid manure application.