• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.3
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• pp.199-203
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• 2006

In the late growth stage of rice plant, the growth declines even though they grow well in early growth stage. This phenomenon is called autumn declining and it often accompanies the infection of Helminthosporium leaf spot disease. This study was carried out to identify the related environmental factors and to establish the integrated control system of Helminthosporium Leaf Spot Disease in rice. The total area of infected paddy field by Helminthosporium leaf spot was 470 ha in 2000 and 1,004 ha in 2001, which occupied about 1% of the total paddy area in Gyeongbuk province, Korea. The ill-drained sandy paddy occupied 50% of the total area of infected paddy fields and followed by sandy paddy (28%). Comparing the content of soil elements between infected and normal paddy, it was clarified that the organic matter content of normal was higher than that of infected paddy and the contents of inorganic elements such as Mn, Fe, Zn and available $SiO_2$ were also higher in normal paddy. The results of comparing the inorganic elements between infected and normal rice plants also showed the same results. The contents of inorganic elements such as MgO, $SiO_2$, Fe, Mn were higher in normal rice plants. Especially highly significant difference of $SiO_2$ content on both soil and rice plants was noticeable.

• Korean Journal of Environmental Agriculture
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• v.17 no.3
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• pp.211-214
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• 1998

Changes in physico-chemical properties and major nutrient contents were investigated in the soil of paddy fields during fallow period. Weed vegetation change in the fallow paddy fields was also examined. As the fallow period became longer, organic matter content in the paddy soil has gradually increased. Soil pH of the paddy fields has not changed until three years of fallow period and thereafter slightly increased. Cation exchange capacity of the paddy soil, and exchangeable N, K, Ca and Mg contents in the soil tended to decrease until three years of fallow period and then increase with the prolonged fallow period. As the fallow period became longer, available $P_2O_5$ content in the paddy soil has continuously decreased. Available $SiO_2$ content in the paddy soil has not changed until three years of fallow period and thereafter increased. The vegetation in the fallow paddy fields have mostly been occupied by the weeds of the Gramineae, Cyperaceae, and Compositae. As the fallow period became longer, the weeds of the Polygonaceae and Juncaceae have increased, whereas the weeds of the Leguminosae, Commelinaceae, Pontederiaceae, and Onagraceae have gradually disappeared. However, the weeds of the Gramineae and Cyperaceae have always been dominant in the paddy fields during the fallow paddy period.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.8
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• pp.1292-1297
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• 1999

A preference test on feed and nutrient intakes were conducted on four male ($1.25{\pm}0.08kg$) and four female ($1.21{\pm}0.15kg$) lesser mouse deer (Tragulus javanicus) in captivity. Each animal was kept in individual cages placed in a well-ventilated animal house. The experiment was conducted in two weeks, where the first week was for adaptation to the feeds and the second week for measurements of nutrient intake, nutrient digestibility and nitrogen balance. The feeds offered were kangkong (Ipomoea aquatica), long bean (Vigna sinensis) and french bean (Phaseolus vulgaris) as roughages and proteinaceous feeds; sweet potato (Ipomoea batatas) and carrot (Daucus carota) as carbohydrate-rich feeds; and commercial rabbit pellet (0.3 cm diameter and 0.5 cm long) as a complete feed. The dry matter (DM) content of each feed in the order mentioned above was 7.1, 6.1, 3.9, 18.5, 6.2 and 87.6%, respectively. Long bean had the highest protein (CP) content (29.7%), while sweet potato had the lowest (6.2%). The CP contents of other feeds were within the range of 14.2 - 25.1%. Among the feeds, carrot had the lowest energy content (3.83 kcal/g) and long bean the highest (4.67 kcal/g). When fresh weight of the feed was considered, the male mouse deer consumed sweet potato the most ($86.3{\pm}12.90g/d$), but the female had a high preference for carrot ($79.2{\pm}9.76g/d$). The other feeds were consumed in lesser amounts. However, in terms of DM of the feed, the amount of commercial pellet consumed was the highest for both male ($45.0{\pm}5.10%$) and female ($44.7{\pm}7.38%$) mouse deer, followed by sweet potato ($33.1{\pm}4.43%$ and $22.4{\pm}7.73%$ for male and female, respectively). Significant (p<0.05) differences in DM, organic matter (OM) and gross energy (GE) intakes were observed between male and female mouse deer. The male consumed higher amount of DM, OM and GE than the female. The total DM intake was $40.7{\pm}2.24g/d/kg$ $W^{0.75}$ for male and $35.9{\pm}1.72g/d/kg$ $W^{0.75}$ for female mouse deer. Percentage digestibilities of DM, OM, CP and GE were within 72.7~80.8% and were not significantly different between male and female mouse deer. However, male mouse deer had significantly (p<0.05) higher digestible DM, OM and GE intakes than the female. Both male and female mouse deer were in positive nitrogen balance (0.6 g N/d/kg $W^{0.75}$). The male mouse deer gained $7.6{\pm}3.45g/d$, while the female gained $4.3{\pm}2.40g/d$.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.4
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• pp.562-568
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• 2017

Objective: The hull attached to the barley kernel can be mechanically removed thus reducing the fiber content of the barley. This experiment was carried out to evaluate the effects of partial dehulling on the nutrient digestibility as well as the digestible energy (DE) and metabolizable energy (ME) content of barley in pigs. Methods: Two hulled barley samples (high fiber barley [HF] and low fiber barley [LF]) with either high or low fiber contents were obtained from the Hubei and Jiangsu Provinces of China. A portion of the two barleys was mechanically dehulled (dehulled high fiber barley [DHF] and dehulled low fiber barley [DLF]). Thirty barrows (initial $BW=31.5{\pm}3.2kg$) were assigned to one of five diets in a randomized complete block design. The five diets consisted of 96.9% corn, HF, LF, DHF, or DLF supplemented with 3.1% minerals and vitamins. Each diet was fed to six barrows housed in individual metabolism crates for a 10-d acclimation period followed by a 5-day total but separate collection of feces and urine. Results: The daily loss of gross energy (GE) in feces was lower (p<0.01) for pigs fed DHF than for those fed HF. The daily N intake and fecal N loss were lowest (p<0.01) for pigs fed the corn diet. The DE and ME as well as the apparent total tract digestibility (ATTD) of dry matter, GE, organic matter, neutral detergent fiber (NDF) and acid detergent fiber (ADF) of DHF or DLF were higher (p<0.01) than the values in HF and LF, respectively while the values except the ATTD of NDF and ADF in DLF were higher (p<0.01) than the values in DHF and were comparable to corn. Conclusion: The DE and ME contents as well as the ATTD of nutrients in both DHF and DLF barley were improved compared with the HF and LF barley. Moreover, the nutritive value of DLF barley was comparable to the yellow-dent corn used in the study.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.2
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• pp.252-262
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• 2018

Objective: An experiment was conducted to evaluate dietary supplemental trace mineral source and deletion on mineral content in tissues. Methods: Weanling crossbred pigs (n = 144; 72 barrows and 72 gilts; body weight [BW] = $7.4{\pm}1.05kg$) were used. A basal diet was prepared, and trace mineral premix containing either inorganic (ITM) or organic (OTM) trace minerals (Cu, Fe, Mn, and Zn) was added to the basal diet. Pigs were blocked by sex and BW and randomly allotted to 24 pens for a total of 6 pigs per pen, and fed a diet containing either ITM or OTM supplemented at the 1998 NRC requirement estimates for each of 5 BW phases (Phase I to V) from 7 to 120 kg. The trace mineral supplementation was deleted for 6, 4, 2, and 0 wk of Phase V; regarding nutrient adequacy during this phase, the indigenous dietary Fe and Mn was sufficient, Cu was marginal and Zn was deficient. Results: At the end of Phase IV, Mn content (mg/kg on the dry matter basis) was greater (p<0.05) in heart (0.77 vs 0.68), kidney (6.32 vs 5.87), liver (9.46 vs 8.30), and longissimus dorsi (LD; 0.30 vs 0.23) of pigs fed OTM. The pigs fed OTM were greater (p<0.05) in LD Cu (2.12 vs 1.89) and Fe (21.75 vs 19.40) and metacarpal bone Zn (141.86 vs 130.05). At the end of Phase V, increased length of deletion period (from 0 to 6 wk) resulted in a decrease (linear, p<0.01) in liver Zn (196.5 to 121.8), metacarpal bone Zn (146.6 to 86.2) and an increase (linear, p<0.01) in heart Mn (0.70 to 1.08), liver Mn (7.74 to 12.96), and kidney Mn (5.58 to 7.56). The only mineral source by deletion period interaction (p<0.05) was observed in LD Zn. Conclusion: The results demonstrated differential effects of mineral deletion on tissue mineral content depending on both mineral assessed and source of the mineral.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.8
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• pp.3887-3896
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• 2013

The aim of this study was to select yeast strain for quality optimization of distilled spirit which is prepared using rice. Five yeasts strains were compared for their brewing characteristics and showed normal fermentation pattern, but songcheon yeast(Y1) and distillery yeast(Y5) revealed higher fermentation ability than other samples tested. The analyzed results of fermented mashing showed that the distillery yeasts(Y4, Y5) had significantly much higher alcohol content, and songcheon yeast(Y1), distillery yeasts(Y4, Y5) had significantly higher ester content than other samples tested respectively, while the distillery yeasts(Y3, Y4, Y5) had significantly higher organic acid content than other samples tested. The analyzed results of distilled spirits which were distilled using copper distillery apparatus showed that the songcheon yeast(Y1) and distillery yeast(Y5) had a higher yield compared to other samples tested. In addition, the results of the aroma compounds such as ester and higher alcohol of distilled spirits among the five yeasts tested were similar to the analyzed results of fermented mashing. Siha aktivhefe 6 brennereihefe(Y5) indicated the highest overall preference including sensory evaluation and was selected as best yeast strain for quality optimization of distilled spirit which is prepared using rice.

• Microbiology and Biotechnology Letters
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• v.17 no.6
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• pp.568-573
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• 1989

As a way to determine the optimal culture conditions for the production of ${\gamma}$-linolenic acid by Mucor sp. KCTC 8405P, the influence of different carbon and nitrogen sources, initial pH, and C/N ratio of medium was investigated. Glucose was found to be the best carbon source in terms of lipid content and ${\gamma}$-linolenic acid yield. Ammonium sulfate and organic nitrogen sources such as urea and peptone resulted in relatively increased lipid and ${\gamma}$-linolenic acid production. The highest accumulation of lipid was obtained at a C/N ratio of 56.6 using glucose and (NH$_4$)$_2$SO$_4$ as carbon and nitrogen source, respectively. It was found that the lipid content increased significantly with increasing initial pH of medium up to pH 9.0. The influence of mixed carbon source on the ${\gamma}$-linolenic acid yield was also investigated. High accumulation of lipids, 315 mg/100 ml medium, and 13-14% of ${\gamma}$-linolenic acid content in the cellular lipid were obtained in a shaking culture containing 3% of glucose and 2% sodium acetate as carbon source and 0.1% of (NH$_4$)$_2$SO$_4$ as nitrogen source at pH 8.0.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.1
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• pp.47-52
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• 2010

Physical, chemical and biological properties of soils and cadmium(Cd) content of Artemisia princeps var. orientalis collected from 10 metalliferous mines were analysed. Cd contents of unplanted soils and rhizosphere soils were not significantly different(p < 0.05), and mean values were 5.92 and 5.91 mg/kg, respectively. In addition, Cd content of rhizosphere soils were correlated with Cd content of Artemisia princeps (p < 0.05, ${R^2}_{shoot}$ = 0.3120, ${R^2}_{root}$ = 0.4177). Minimum data set(MDS) of soil quality parameters for statistical assessment of Cd uptake was established by principal component analysis, and it was identified as organic matter(OM), dehydrogenase activity(DHA), pH, exchangeable Mg. According to multiple regression analysis using the MDS, coefficients of determination ($R^2$) for Cd uptake of shoot and root of Artemisia princeps were found to be 0.3418 and 0.5121, respectively. This suggests that statistical soil quality assessment using the MDS seems a useful tool to interpret heavy metal uptake of plant.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.4
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• pp.255-261
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• 2007

Soil aggregates, resulting from physico-chemical and biological interactions, are important to understand carbon dynamics and material transport in soils. The objective of this study is to investigate stable macro-aggregate (> 0.25mm diameter) in wet sieving (SM) and their relation to soil properties in 15 sites. The clay contents of soils were ranged from 1% to 33%, and their land uses included bare and cultivated lands of annual upland crops, orchard, and grass. Undisturbed 3 inch cores with five replicates were sampled at topsoil (i.e., 0- to 10-cm depth), for analyzing SM and physico-chemical properties, after in situ measurement of air permeability. SM of sandy soils, with clay content less than 2%, was observed as 0%. Except the sandy soils, SM of soils mainly depended on land uses, showing 27%~35% in soils with annual plants such as vegetable and corn, 51% in orchard, and 75% in grass. This sequence of SM is probably due to the different strength of soil disturbance like tillage with different land uses. SM had significant correlation with cation exchange capacity, organic matter content, sand, clay, silt, bulk density, and exchangeable potassium (K) and magnesium (Mg), whereas fluctuating properties with fertilization such as pH, EC, and water soluble phosphorus weren't significantly correlated to the SM. Particularly, exchangeable calcium (Ca) had significant relation with SM, only except soils with oversaturating Ca. This study, therefore, suggested that SM could perceive different land uses and the change of soil properties in soils, necessarily considering soil textures and Ca over-saturation.

• Food Science and Preservation
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• v.23 no.3
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• pp.291-300
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• 2016

Kiwifruit (Actinidia chinensis, Hayward) was stored at $25^{\circ}C$ for 0~30 days and investigated to find out the optimum storage time to obtain the best physical and functional properties for consumers' preference. Kiwifruits was stored at different time period (0, 5, 10, 15, 20, and 30 days) for investigating their physiochemical quality, nutritional components, and functional characteristics. Kiwifruits stored for 20~30 days showed the best physiochemical quality such as higher total acidity and proper firmness. They were also more enriched with dietary fibers, free sugar, and organic acid, although no significant changes were observed in crude protein, crude fat, and moisture content. For functional properties, kiwifruits stored for 20 days showed significantly higher contents of total phenolics, flavonoids, and actinidin. In addition, it showed stronger antioxidant activity, whitening effect, and proteolytic activity when compared with other samples. SDS-PAGE analysis showed the presence of actinidin enzyme in kiwifruits. These results indicated that the kiwifruits stored for 15~20 days possessed excellent quality and high concentrations of nutritional and functional compounds, which could be best for both fresh consumption and product processing.