• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.1
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• pp.72-78
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• 2020

In this study, miscanthus with C/N ratio of 224 were applied to the soil and treated with 0 (control), 10 tons and 20 tons·ha^-1 to improve the soil and promote crop growth. As a result, soil organic matter content increased from 11.0 g·kg^-1 before the test to 16.3 after 3 years. Soil cation exchangeable capacity increased to 15.3 cmol_c·kg^-1 after 3 years. In the sweet sorghum, stem was the most thickest at 20 tons·ha^-1 application of miscanthus and the highest juice amount per plant was 60 ml. The yield index multiplied by the soluble solids content of juice and juice amount was the highest at 1,913 for 10 tons application and 1,851, 1,839 for 20 tons, control respectively. Number of sweetpotato storage root were 2,9 in 20-tons application plot, the same as control, and 10-tons application plot was 3.6, the most. Two-year average yields of 20 tons plot and control were low at 2,579 kg/10a and 2,708 respectively, and 10 tons plot was the highest at 3,289. For onions, the biomass application did not effect the yield. but onion plant and leaf length were longer in 20 tons plot than in control or 10 tons. The yield of garlic was 2,630~2,901 kg/10a and there was no effect of miscanthus application. Plot of 10 tons application were the longest in plant and leaf length, and the number of scale was 8.2-8.3 per in bulb, and 8.9 tons·ha^-1 in control. Therefore, it was confirmed the possibility that miscanthus biomass application of about 10 tons·ha^-1 could improve the soil condition and promote crops growth and yield.

• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.545-553
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• 2019

This study was conducted to determine whether the water in which nitrate accumulated during long-term fish culture in an aquaponics system without water exchange could be removed and reused as catfish-culturing water. The catfish (Silurus asotus) were cultured in the urban aquaculture system using BFT (Biofloc Technology) aquaculture and an aquaponics system (two rearing tanks, 3 tons each) without exchanging the rearing water. After 151 days (from March to August) of rearing, 2.8 g of fry had grown to an average weight of 171.3 g (total weight, 56.53 kg) and 235.5 g (total weight 71.1 kg), respectively. The overall survival rate was 65% in the urban aquaculture system. However, the survival rate was 77.7% before separation into the two tanks. The survival rates after the separation were 92.9% and 78.0%. In the early biofloc watermaking process, there was a high mortality rate. After water stabilization, the mortality rate decreased and some mortality occurred during the period when the total amount of suspended solids (TSS) increased. The results of monthly blood analysis of the catfish showed that the AST concentration was significantly higher in April. Blood ALT levels and triglycerides showed no difference in the rearing period and the glucose, cholesterol, and total protein levels were significantly higher in July. There was no difference in the other periods. The plants produced by the aquaponics system using catfish-rearing water were lettuce, basil, chard, and red chicory. These showed smooth growth and a total of 148.85 kg of plants were harvested in five months. It was possible to remove nitric acid from the aquaponics system and reuse it as catfish-rearing water. Maintaining proper plant quantity according to the capacity of the catfish showed that the combination of agricultural and aquatic products was possible.

• Journal of Embryo Transfer
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• v.21 no.1
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• pp.45-51
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• 2006

This study was carried out to investigate effect of claw trimming on milk yield and its composition in Holstein at different lactation stages. 1 . There was no difference in daily milk yield between control and claw trimming in early, mid and late lactating Holsteins. 2. Somatic cell count (SCC) was lower in early lactation and it was higher in late lactation when claws were trimmed in Holstein. However, claw trimming did not affect SCC during mid lactation in Holstein. 3. Milk fat, protein and total solids were decreased during late lactation in Holstein after claw trimming. However, milk composition was not affected by claw trimming in early and mid lactating Holsteins.

• Horticultural Science & Technology
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• v.32 no.3
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• pp.289-295
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• 2014

This research was conducted to investigate a difference in quality according to control of fruit load and cluster weight when seeded 'Heukboseok' grape was grown in a conventional cultivation system. Clusters per vine were set to harvest 1,500 kg, 1,800 kg, and 2,200 kg grapes per $990m^2$. In p lots t reated t o produce 1,800 kg grapes, clusters were set to 3 grades produce grapes with 350 g, 500 g, and 700 g in cluster weight. Based on color chart (National Institute of Horticultural & Herbal Science, Rural Development Admnistration) which show maturation stage for 'Kyoho' grape, grapes with higher than grade 9 were harvested at 80 and 90 days after full bloom, and the r est of them were harvested a t 100 days after full bloom. The final yield of 'Heukboseok' grape was the lowest in target yield of 1,800 kg with 700 g clusters with 75.5% of target yield, but 92.1%-100.1% of target yield were harvested in other treatments. Among treatments with several fruit setting, 83.3% of grapes harvested in treatment to produce 1,500 kg grapes as a target yield at 90 days after full bloom. Among the treatments with different cluster weights, 93.5% grapes were harvested in the treatment with 350 g in cluster weight. 'Heukboseok' grape showed rapid maturation pattern with no significant difference in either soluble solids content or acidity between 90 days from 80 days after full bloom. Therefore, to prevent flesh softening, it is appropriate to harvest fruit at 90 days after full blooms, and both yield and cluster weight were important factors influencing the quality of the fruits in 'Heukboseok' grape. It is confirmed that coloring and firmness was influenced by the final yield and weight per cluster, respectively. Therefore, the yield should be set as grape of 1,500 kg per $990m^2$ in target yield, and cluster weight should be adjusted to 350 g to produce grape of 1,800 kg with the fruits of high quality. It is considered to be hard to produce grape of high quality with 700 g in cluster weight in 'Heukboseok' grape.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.3
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• pp.308-318
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• 2013

Korean soybean varieties, 'Seonyu' and 'Hwangkeum' were planted in 2012, and three temperature gradient, Tc($19.8^{\circ}C$, ambient temperatured), $Tc+1.7^{\circ}C$, and $Tc+2.5^{\circ}C$, were artificially created by controlling the green house system during seed filling period. Mature seeds that developed under these conditions were analyzed for variances in physicochemical properties. The 100-seed weight and seed-coat ratio of soybean were decreased, but small seed rate was increased by high temperature during seed filling period. Protein content was increased, but oil content was decreased significantly with increasing the seed filling temperature. The decrement of carbon to nitrogen ratio (C/N), and the increment of monosaccharide, fructose and sucrose, in seeds explained that carbohydrate assimilation during seed filling was restricted by high temperature. Rapid increments of seed volume and weight were observed in the seeds of high seed filling temperature, but as soaking time increased the highest values were observed in the seeds of ambient seed filling temperature. The 100-seed weight and seed-coat ratio of soybean were closely related not only to the increment of soaking volume and weight, but also the increments of total dissolved solids (TDS) and electro conductivity (EC). Whereas protein content and C/N ratio showed less relationship with the soaking properties, but they had a positive correlation with TDS and EC. From the results, it was considered that high values of TDS and EC in the seeds of high temperature were mainly due to the incomplete conversion of assimilates into storage compounds. However, sugar content showed less influence on the soaking properties and the values of TDS and EC.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.3
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• pp.172-183
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• 2017

Germinated brown rice (GBR) has received considerable attention over the last decade as a means of enhancing the nutritional value and health-promoting functions of rice. The effect of germination on the physicochemical and textural properties of brown rice (BR) was investigated in different rice varieties (Samkwang, Misomi, Chindeul, and Hyeonpum). Cooking properties, such as water absorption, expanded volume, and soluble solids were significantly increased by germination in all rice varieties. Textural properties (hardness, toughness, adhesiveness, and stickiness) of cooked samples were determined using a texture analyzer. Hardness and toughness were decreased by germination, whereas stickiness and adhesiveness increased significantly. These results revealed that germination leads to improvements in the cooking and eating properties of BR. In Rapid Visco Analyzer (RVA), significant reductions were observed for peak viscosity, break down, set back, and final viscosity after germination. Although the amylose content of Misomi was slightly decreased by germination, that of other varieties increased significantly. Germination induced no noticeable change in the average chain length of amylopectin in Misomi, Chindeul and Hyeonpum, but led to a significant increase in Samkwang.

• Journal of Dairy Science and Biotechnology
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• v.30 no.1
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• pp.1-10
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• 2012

The objective of this study was to evaluate the rheology and sensory properties of Mozzarella cheese manufactured by the traditional method and by an ultrafiltration technique and to attempt to develop a new type of Mozzarella cheese. We noted 3 observations. (1) The initial pH observed for raw milk and retentate of ultrafiltration (CF 2 and CF 3) did not vary much. However, there was a significant difference in the pH at stretching. The initial TAwas significantly different between the raw milk and retentate obtained by ultrafiltration (CF 2 and CF 3). However, no differences were observed in TA at stretching. (2) The predicted yield (Y50), adjusted to 50% total solids (TS), was affected by the concentration factor, fat content, and addition of starter and rennet. The Y50 increased with the concentration factor. 3) Hardness, elasticity, cohesiveness, and brittleness were affected by fat content, and addition of starter and rennet. The hardness, elasticity, and brittleness of Mozzarella cheese made from the retentate of ultrafiltration (CF 2 and CF 3) were higher than in Mozarella cheese made by the traditional method; however, the cohesiveness decreased during storage at $4^{\circ}C$ over a period of 3 months. (4) Flavor, body texture, appearance, color, and firmness decreased with bacterial count, fat content, and addition of starter and rennet. The results of the sensory evaluation of the Mozzarella cheese made from the retentate of ultrafiltration (CF 2 and CF 3) changed during storage at $4^{\circ}C$ over a 3-month period.

• Korean Journal of Environmental Agriculture
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• v.28 no.2
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• pp.97-105
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• 2009

A constructed wetland which was composed of aerobic and anaerobic areas was evaluated for 3 years to effectively treat the sewage produced in farming and fishing communities. For 3 years in a constructed wetland, biochemical oxygen demand(BOD), chemical oxygen demand(COD), suspended solids(SS), total nitrogen(T-N), and total phosphorus(T-P) in effluent were 0.2${\sim}$11.8, 1.0${\sim}$41.9, 1.1${\sim}$6.5, 4${\sim}$60 and 0.02${\sim}$3.51 mg/L, respectively. Removal rate of BOD, COD and SS in effluent were 97, 92 and 99%, respectively, in the third year. As time goes by, removal rate of T-N and T-P in treated water in aerobic area and effluent were gradually increased in a constructed wetland. In the third year, removal rate in effluent were 62 and 73%, respectively. By the seasons, removal rate of BOD, COD, SS, T-N and T-P were 97${\sim}$98, 87${\sim}$91, 99, 43${\sim}$61 and 76${\sim}$86%, respectively. Removal rate of BOD, COD, SS and T-P were not affected by the seasons, but that of T-N in winter and spring were decreased than the other seasons.

• Horticultural Science & Technology
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• v.17 no.2
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• pp.118-122
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• 1999

Quality changes of fruit vegetables were investigated during simulated export and marketing to find out the optimum shipping temperature. Fruit vegetables were loaded into a small refrigerated-container and kept for four days at various temperatures, and fruit quality was assayed immediately after harvest, 4 days after storage and 4 days after marketing at ambient temperature. In 'Back Seong Ilho' cucumber fruits, fresh weight loss was further reduced at $13^{\circ}C$ and $11^{\circ}C$ than at $15^{\circ}C$ and room temperature. Soluble solid contents remained at relatively lower levels when cucumbers were stored at $13^{\circ}C$ and $11^{\circ}C$. In 'Chun Ryang' eggplant fruits, fresh weight loss was greatly increased at all the temperatures (room, $12^{\circ}C,\;9^{\circ}C,\;and\;6^{\circ}C$). However, flesh browning, a primary quality factor of eggplant fruit, was most effectively inhibited at $9^{\circ}C$, whereas chilling injury occurred in fruit flesh at $6^{\circ}C$. Water loss of 'Eals Seinu' melon fruits was most inhibited and soluble solid contents at harvest were maintained for the longest period at $4^{\circ}C$. In 'Pe Pe' cherry tomatoes, storage at $10^{\circ}C$ and $7^{\circ}C$ seemed to more effectively inhibit metabolic changes and the incidence of cracking, the severest disorder than room temperature. But the fruits stored at $10^{\circ}C$ contained higher level of soluble solids than those at $7^{\circ}C$. The overall results suggest that the optimum shipping temperature range is 11 to $13^{\circ}C$ for cucumbers, around $9^{\circ}C$ for eggplant fruit, $4^{\circ}C$ for melons, and $10^{\circ}C$ for cherry tomatoes.

• Horticultural Science & Technology
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• v.30 no.4
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• pp.345-356
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• 2012

We investigated the changes of fruit quality parameters, polysaccharide contents and cell wall components during maturation and ripening of two Korean pear cultivar 'Hanareum' and 'Manpungbae' compared with 'Niitaka' pear (Pyrus pyrifolia Nakai) which showed different physiological maturity based on days after full bloom (DAFB). Flesh firmness decreased continuously with fruit development and maturation, reaching a final level of 29.4, 33.5, and 27.4N at maturity in 'Hanareum' (127 DAFB), 'Manpungbae' (163 DAFB), and 'Niitaka' (170 DAFB), respectively. The level of ethylene production was very low in early season 'Hanareum' pear which showed at most 0.39 ${\mu}L{\cdot}L^{-1}$ at maturity and no ethylene was detected in 'Manpungbae' and 'Niitaka' at maturity. Fructose was the most abundant soluble sugar during fruit maturation in the pears tested and an increase of sucrose was observed during fruit ripening in the Asian pears commonly. Ethanol insoluble solids (EIS) content decreased gradually with different levels among the pear cultivars as fruit ripens consisted of 10.79, 12.72, and 12.75 $mg{\cdot}g^{-1}$ FW. The amount of total soluble polyuronides was higher in early season cultivars 'Hanareum' than those of mid-season cultivar 'Manpungbae' and 'Niitaka'. In 'Niitaka' which harvested most late season, the level of 4% KOH soluble hemicelluloses was lower than 'Hanareum' and 'Manpungbae' and maintained constantly during fruit ripening period. Cellulosic residues were determined high level in 'Niitaka' which showed 612.33 ${\mu}g{\cdot}mg^{-1}$ EIS at maturity when compared with 'Hanareum' (408.0 ${\mu}g{\cdot}mg^{-1}$ EIS) and 'Manpungbae' (538.67 ${\mu}g{\cdot}mg^{-1}$ EIS). The main constituents of cell wall neutral sugars which consisted of arabinose, xylose, galactose, and glucose were decreased gradually with onset of fruit ripening regardless of cultivar. Arabinose which was predominant in 'Hanareum' pear decreased at the last stage of ripening, but the changes of cell wall neutral sugar during ripening were not occurred in 'Niitaka' pear. The change of molecular mass distribution in water soluble pectin observed dominantly at the early stage of fruit development. Depolymerization of 4% KOH-soluble hemicelluloses and degradation of xyloglucan showed in early-season cultivar 'Hanareum' during fruit maturation, and degradation of those fractions were detected only at the early stage fruit development in mid-season cultivar 'Manpungbae' and 'Niitaka'. The molecular mass profile of CDTA soluble pectin, $Na_2CO_3$-SP and 24% KOH soluble hemicelluloses showed no significant change during fruit maturation regardless of cultivar.