• Korean Journal of Agricultural Science
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• v.41 no.4
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• pp.327-334
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• 2014

Light intensity is one of the most important requirements for plant growth, affecting growth, development, survival, and crop productivity. Sunlight is the main energy source on Earth which is energy used by photosynthesis to convert light energy to chemical energy. In this study, the light use efficiency and photosynthetic characteristics of high-quality rice cultivars were evaluated after shading on ripening stage. For the study, we treated of three levels of shade (0, 50 and 70%) on rice at ripening stage and two levels of nitrogen (9 and 18 kg/10a) used three high yielding rice cultivars, such as Boramchan, Hopum, and Honong. The shade was given for the respective plots from heading up to harvesting. We were performed to determine growth survey, SPAD and chlorophyll fluorescence every 10 days interval after shading on ripening stage. At harvest stage, grain yield and yield components were determined. Results of analysis of the results representing the maximum photosynthetic efficiency of PSII, Fv/Fm, and SPAD were decreased by depending on the time at full sunlight. But shade treatments were not changed and a significant difference among cultivars did not appear. Compared with the full sunlight, shade treatments significantly delayed ripening rate and decreased rice quality of cultivated rice. Therefore, rice yield, can be reduced in proportion to the shading density is apparent, the rate of decrease was not observed difference between varieties, when protected from light 70%, and decreased to less than 50%. The adverse effects of low light intensity on the yield and yield components were not able to significantly minimize by the nitrogen level.

• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.4
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• pp.254-261
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• 2014

This study was to assess the effect of sowing mixed legume forage and applying cattle manure on the productivity and feed value of whole-crop barley (WCB) as a representative of winter crops and to estimate feeding capacity of Korean native cattle (Hanwoo) per unit area by defining optimal application level of cattle manure for more fertile soil and manure recycling for the purpose of reduced environmental pollution and efficient production of organic forage contributable to production of organic animal products. Sowing mixed legume forage significantly (p<0.05) increased yields of dry matter (DM), crude protein (CP) and total digestible nutrients (TDN) for WCB compared to WCB alone sowing, but there was no difference between mixed sowing treatments. The yields of DM, CP and TDN were significantly (p<0.05) highest in 100~150 kg N/hg. The CP and acid detergent fiber (ADF) contents were highest in mixed sowing with hairy vetch, followed by sowing mixed forage pea and WCB alone (p<0.05). There were no differences in CP and neutral detergent fiber (NDF) contents among cattle manure application levels. As nitrogen application level increased, ADF content increased (p<0.05), but TDN content decreased (p<0.05). Feeding capacity of organic Hanwoo (head/ha) weighing 450 kg of body weight with 400 g of daily gain significantly (p<0.05) increased due to mixed sowing with legume forage, and with increasing application levels of fermented cattle manure, feeding capacity significantly (p<0.05) increased. The results indicate that mixed-sowing of WCB and legume forage not only cut nitrogen application level of fermented cattle manure by over 50 kg per ha but also increased their feed value and productivity, and feeding capacity. This would be contributable to diversity of forage resources as well as production of organic animal product by creating low cost and high quality of forage.

• Journal of Korean Society of Forest Science
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• v.70 no.1
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• pp.45-54
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• 1985

The experiment was conducted to test the effects of ectomycorrhizal inoculation and soil moisture regime on growth and nutrient uptake of Pinus rigida seedlings. Two-year-old seedlings inoculated with either Pisolithus tinctorius or Thelephora terrestris were used for this experiment. There were two moisture treatments and four phosphate treatment levels with three replications. Height and root collar diameter growth and dry weight increase were measured and nitrogen, phosphorous, and potassium in the tissue were analyzed three months after the initiation of phosphate and moisture regime treatment. Results are as follows; 1) Height growth of seedlings was not affected in all treatments. (mycorrhizae, fertility, moisture). 2) High moisture regime increased root collar diameter growth 2.7 times as large as low moisture regime. 3) In low moisture regime, net production increased 26% in seedlings inoculated with Pisolithus tinctorius and increased 72% control seedlings. 4) In high moisture regime, net production of inoculated seedlings with Pisolithus tinctorius increased four times as much as that of control seedlings but increased $P_2O_5$ in fertility level did not affect net production. 5) In uptake of nitrogen, phosphate, and potassium, Pisolithus tinctorius - inoculated seedlings increased uptake by 1.9, 1.8, and 1.5 times, respectively, as much as control seedlings. 6) Increase in $P_2O_5$ fertility level enhanced the uptake of $P_2O_5$ in Pisolithus tinctorius - inoculated seedlings, but not affected the uptake of $P_2O_5$ in control seedlings. 7) Increase in $P_2O_5$ fertility levels enhanced the uptake of $K_2O$ in Pisolirhus rinctorius - inoculated seedlings.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.3
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• pp.285-296
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• 1995

Anatomical studies of sink tissues are required for better understanding the biological plant growth system and energy metabolism. Kinematics of root growth zones of two genotypes of tall fescue (Festuca arundinacea Schreb.) receiving 50 or 200 ppm N were determined. Longitudinal anatomy and cell dynamics of root growth zones were studied and calculated. The root growth zone is organized similarly to the leaf growth zone which has cell division, elongation, and maturation zones, but the root growth zone is only about 3.0 mm long compared to 25 to 30 mm for the leaf growth zone. The root cap extends about 0.4 to 0.5 mm from the apical initial, while the cell elongation zone for both cortical and metaxylem cells extends about 3.3 mm from the apical initial for both genotypes and N levels. Root cap cells elongate from an initial length of about 5$\mu{m}$ long to a final length of about 40$\mu{m}$ before being sloughed. Initial lengths of cortical and metaxylem cells were about 8.5 $\mu{m}$ and 13.0 $\mu{m}$, respectively. Elongation of cortex and metaxylem cell showed sigmoidal curves with final lengths of about 120 $\mu{m}$ for cortex cells and 650 $\mu{m}$ for metaxylem cells. Initial size and final size for both types were not affected by N level, but cell fluxes and cell elongation rates of cortical and metaxylem cells were about double in low N. Cell production rates were about 5 to 6 times higher in cortical cells than in metaxylem cells. Differences in N caused a larger change in cell production rate, duration of cell elongation, and relative cell elongation rate than did the genotypes. These data indicate that N application affects root growth longitudinally by changing cell production rate and elongation rate.

• Food Science and Preservation
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• v.19 no.2
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• pp.301-307
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• 2012

The quality of brown rice vinegar that was produced via static culture (A) was compared with the quality of three types of domestic commercial brown rice vinegar (B, C, and D) and of three types of Japanese brown rice vinegar (E, F, and G). The results showed titratable acidity levels of 6.39%, 4.52-6.32%, and 4.51-4.89% in the static-cultured brown rice vinegar, the domestic commercial brown rice vinegars, and the Japanese brown rice vinegars, respectively. The pH levels were 3.28, 2.58-2.97, and 3.03-3.27 in the static-culture brown rice vinegar, the domestic commercial brown rice vinegars, and the Japanese brown rice vinegars, respectively, which show similar values of the static-culture brown rice vinegar and the Japanese brown rice vinegars. The total nitrogen (TN) values of the static-culture brown rice vinegar, the domestic commercial brown rice vinegars, and the Japanese brown rice vinegars were 0.24, 0.03-0.16, and 0.12-0.17, respectively, with the highest value for the static-culture brown rice vinegar, substantial differences among the domestic commercial brown rice vinegars, and similar contents among the Japanese brown rice vinegars. For free sugar, glucose was either detected only in a small quantity or not detected at all in the static-culture brown rice vinegar and the Japanese brown rice vinegars, which showed perfect fermentation. The glucose and maltose contents were higher in the domestic commercial brown rice vinegars. The organic acid content of the static-culture brown rice vinegar was similar to that of the Japanese brown rice vinegars. Therefore, the total acidity content, TN value, sensory property, and quality of the static-culture brown rice vinegar (A) were superior to those of the domestic and Japanese brown rice vinegars.

• Journal of Life Science
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• v.25 no.7
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• pp.740-747
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• 2015

This study was carried out to evaluate changes in the meat quality and antioxidation activity in the loin and ham of Korean Native Black Pigs (KNBP) during frozen storage at −18℃ for 150 days. The pH value of the loin was decreased as storage days progressed, while the pH value of the ham showed no consistent changes with storage days. The lightness (L*) of the loin did not show any significant reduction until day 120, whereas L* of the ham was significantly declined throughout the storage period (p<0.05). The redness (a*) values of the loin and ham were significantly decreased as storage progressed. The water holding capacity of the loin was decreased by day 30 and that value was maintained until the end of storage. The initial total numbers of microorganisms in the loin and ham were 4.88 and 5.16 Log CFU/g, respectively and these numbers were significantly decreased by day 30 (p<0.05). The levels of 2-thiobarbituric acid reactive substances (a measurement of lipid oxidation) in the loin and ham ranged from 0.057-0.069 and 0.052-0.087 mg MDA/kg meat, respectively, until storage day 150. Volatile basic nitrogen values of the loin and ham ranged from 15.13-16.55 and 16.05-16.23 mg%. Oxygen radical absorbance capacities and carnosine contents of the loin and ham were significantly decreased during frozen storage for 3 months (p<0.05). In summary, the meat quality of the loin and ham from KNBP was somewhat decreased during frozen storage. However, the levels of antioxidants and dipeptides with antioxidant activity were significantly decreased in pork loin and ham during frozen storage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.6
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• pp.721-726
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• 2009

The objectives of this study were to analyze mineral contents of three rice varieties (Josangheugchal, Heugjinjubyeo and Dongjinchalbyeo) under three different cultural practices: five transplanting time (May 15, May 25, June 4, June 14, and June 24), five harvest times (30, 40, 50, 60, and 70 days) and N-fertilization levels (0.0, 4.5, 9.0, 13.5, and 18.0 kg/10a). Mineral contents of Josangheugchal were increased by late transplanting time with increased nitrogen level; however, it was not significantly different by harvest time. Heugjinjubyeo did not show significant difference in three cultivations. Mineral contents of Dongjinchalbyeo increased at the transplanting time of May 25 and June 14 and according to late harvest time. Also mineral contents of Dongjinchalbyeo that did not show significant difference except for calcium according to different nitrogen levels.

• Food Science of Animal Resources
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• v.28 no.4
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• pp.480-485
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• 2008

In this experiment, 5 treatments consisted of control, probiotics (0.2%; T1), illite (1.0%; T2), activated carbon (1.0%; T3), and hardwood vinegar (1.0%; T4) as diets of chicken were evaluated for 35 days through feeding of 200 male chickens (Arbor Acre Broiler). Thigh muscle from slaughtered chickens were analyzed on pH, volatile basic nitrogen (VBN), thiobarbituric acid reactive substance (TBARS), shear force, and meat color during 10 d of cold storage at $4{\pm}1^{\circ}C$. Groups of T3 and T4 showed higher pH levels compared to the control group, and T4 showed significantly higher value. Over the storage period, all treatment groups showed increase in pH (p<0.05). Values of VBN of T1, T3, and T4 were lower than those of the control group and T2 up to 7 d of storage (p<0.05), but there was no significance at 10 d of storage. Values of TBARS of T3 and T4 were lower than the control group, T1, and T2, while all treated groups showed rapid increase of TBARS values over storage period (p<0.05). Shear force did not show significant difference among treated groups, but it was decreased over storage. Lightness of meat color (L) in treated groups was higher than the control, and T4 showed the highest value during entire storage period (p<0.05). Yellowness levels (b) of T3 and T4 were higher than the control group. These results may suggest the improvement of chicken meat quality and shelf life via the addition 1% activated carbon and 1% hardwood vinegar into feed.

• Journal of the Korea Organic Resources Recycling Association
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• v.26 no.4
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• pp.21-29
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• 2018

The contents of total nitrogen(T-N), phosphate($T-P_2O_5$), and potash($T-K_2O$) are important factors to determine the application rate of the livestock compost to prevent nutrients accumulation and maintain their appropriate levels in arable lands. The concentrations of nutrient, organic matter, salt, water content, heavy metal in livestock compost in circulation were investigated with 659 samples from 2016 to 2017. In order to investigate the fluctuation nutrient contents of livestock composts with the same product name, 19 samples were collected and analyzed T-N, and $T-P_2O_5$, and $T-K_2O$ concentration during two years. The mean levels of T-N, $T-P_2O_5$, and $T-K_2O$ in livestock composts of from 2016 to 2017 were 1.73%, 1.88%, and 1.66%, respectively. The average contents of organic matter, water, and salt were 38.9%, 40.9%, and 1.2%, respectively. There were found that the maximum concentrations of Cr, Ni, Cu, and Zn in some livestock composts were exceeded the criteria of the official standard of commercial fertilizer. The maximum variation coefficient of T-N, $T-P_2O_5$ and $T-K_2O$ content of livestock composts was found to be 24%, 27%, and 50% on average, respectively. In order to manage the nutrients in agricultural soils, it will be reasonable that the error range of T-N and $T-P_2O_5$ content in livestock composts should be recommended to be 27% in mean as variation coefficient in case of displaying the nutrient element in liverstock compost.

• Horticultural Science & Technology
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• v.34 no.4
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• pp.578-586
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• 2016

In this study, we evaluated the effects of soil incorporation of crotalaria as a green manure on the growth and yields of 'Seolhyang' strawberry and inorganic soil nitrogen levels in a greenhouse. Four different N treatments were used, as follows: zero N fertilizer (control), crotalaria, crotalaria with 50% urea, and 100% urea. The recommended N requirement (100% urea) for strawberry was $86kgN{\cdot}ha^{-1}$ and 50% of the recommended N (50% urea) was $43kgN{\cdot}ha^{-1}$. Crotalaria was sowed on June $17^{th}$, 2011 and cultivated for 37 days. The amount of N supply from soil incorporation of crotalaria was $104kgN{\cdot}ha^{-1}$. Strawberry was planted on September $9^{th}$, 2011 and cultivated for 255 days after planting. The concentrations of soluble solids and acidity of strawberry fruits for the crotalaria treatment were higher than for the crotalaria with 50% urea and 100% urea treatments. On the other hand, the growth and yield of strawberry was the highest for the crotalaria with 50% urea and 100% urea treatments, followed by the crotalaria treatment, and the lowest for the control. Soil inorganic N concentration for the crotalaria treatment was continuously decreased to $24mg{\cdot}kg^{-1}$ at the end of the growing season, while crotalaria with 50% urea and 100% urea treatments maintained an inorganic N concentration that ranged from 35 to $50mg{\cdot}kg^{-1}$. These results indicate that the amount of N supply from soil incorporation of crotalaria may not be enough because strawberry yield was lower than for other N treatments. Therefore, additional nitrogen, such as 50% urea after soil incorporation of crotalaria, is recommended.