• Journal of the Korean Wood Science and Technology
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• v.43 no.4
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• pp.411-420
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• 2015

Despite of the same species there is a difference in the tree shape and its wood property due to quantitatiVe and qualitatiVe differences in wood cells by the intra-annual cambial actiVity. The purpose of this study was to proVide the fundamental database of intra-annual cambial seasonal actiVity for red pine in Sokwang-ri and Anmyondo for the determination of their wood qualities. As the results of intra-annual cambial actiVity, the initiation of cambial actiVity of red pine in the plots with Age Class V in Sokwang-ri was in the middle of April and it was at the beginning of April in all plots in Anmyondo. Only the plots with Age Class IX in Sokwang-ri showed relatiVely late initiation of cambial actiVity as between middle of May and middle of June. Except one plot with Age Class IX in Sokwang-ri all plots in both sites showed the same cessation of cambial actiVity as between middle and end of October. According to intra-annual cambial actiVity, the duration of cambial actiVity in Sokwang-ri is shorter than that of Anmyondo. On the other hand, the number of cell diVision of cambial actiVity in Sokwang-ri was more than those of Anmyondo. We could establish the database for intra-annual cambial actiVity for Sokwang-ri and Anmyondo to estimate their wood quality.

• Journal of the Korean Wood Science and Technology
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• v.38 no.6
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• pp.568-578
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• 2010

In this study, the possibility of biodegradation of polychlorinated biphenyls (PCBs) by various white rot fungi was evaluated, and outstanding white rot fungi for the degradation of PCBs were selected. Seven white rot fungi were used to degrade Aroclor 1254 and 1260, which are widely considered to be toxic and difficult to degrade. And the degradation rates of Aroclors by selected white rot fungi were performed by GC analysis. Through the resistance test of white rot fungi on different concentrations of PCBs, the inhibition of mycelial growth of Cystidodontia isubellina was much less than that of others, and this fungus grew faster than others, relatively. Based on this result, it was considered that C. isubellina was selected as degrading fungus for Aroclors. As a result of biodegradation rate of Aroclors by Cystidodontia isubellina, the degradation rate of Arolor 1254 was reached to 57.57% in 13 days, which showed very high degradation rate. Also the degradation rate of Aroclor 1260 by C. isubellina had a tendency of increasing along with increasing incubation day. Maximal degradation rate of Aroclor 1260 was 49.43% at 13 days. Based on this results, it indicated that in comparison with a previous study, high degradation rate was obtained by C. isubellina.

• Journal of the Korean Wood Science and Technology
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• v.48 no.4
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• pp.527-547
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• 2020

Fish pathogens cause not only economic damages to fish farming but also infectious pathogens known as a zoonotic agent. Since the continued use of antibiotics to control fish pathogens entails side effects, materials of natural origin need to be developed. The purpose of this study is to discover coniferous essential oils with excellent antibacterial effects in order to develop antibiotic alternatives. We have extracted essential oils using hydro-distillation from the leaves of Abies holophylla, Pinus thunbergii, Pinus parviflora, Tsuga sieboldii, and Pinus rigitaeda, which are all Pinaceae family. And, we have evaluated antibacterial activity with the extracted essential oils against Edwardsiella tarda, Photobacterium damselae, Streptococcus parauberis, and Lactococcus garvieae, which are fish pathogens. As a result, the essential oils from A. holophylla and P. thunbergii showed the selectively strong antibacterial activity against E. tarda and P. damselae, which are gram-negative bacteria. From GC-MS analysis, it was identified that main component of A. holophylla essential oils are (-)-bornyl acetate (29.45%), D-limonene (20.47%), and camphene (11.73%), and that of P. thunbergii essential oils is α-pinene (59.81%). In addition, we found three compounds: neryl acetate, (-)-borneol, and (-)-carveol, which are oxygenated monoterpenes. These exist in a very small amount but exhibit the same efficacy as essential oil. Therefore, we expect that A. holophylla and P. thunbergii essential oils having excellent growth inhibitory effect against gram-negative fish pathogens can be used as biological products such as feed additives and fishery products.

• Korean Journal of Organic Agriculture
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• v.19 no.1
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• pp.121-134
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• 2011

For this study, Smilex powder, a pesticide, was sprayed on the Altari radish, and then underground water, Chitosan solution (${\times}$500), and wood vinegar solution (${\times}$1000) were evenly sprayed on the Altari radish respectively. Samples of Altari radishs for residual pesticide analysis were taken two hours, 1 day, 7 days, and 15 days after treatments, and the detectable concentration and degradability of procymidone, the pesticide residue, were measured. The results obtained are as follows: 1. When detectable concentration of procymidone within the altari radish was measured, treatment plots sprayed with underground water, Chitosan solution (${\times}$500), and wood vinegar solution (${\times}$1000) were found to show lower detectable concentration than the non-treatment plot which was sprayed with pesticide only. Especially, the treatment plots sprayed with Chitosan solution (${\times}$500), and with wood vinegar solution (${\times}$1,000) showed lower values than the average. 2. When the degradability of procymidone within the Altari radish was measured, the plot treated with Chitosan solution (${\times}$500) and the plot treated with wood vinegar solution (${\times}$1,000) were found to have relatively higher degradability of procymidone. There were not much differences among testing materials in the degradability of residual pesticides. However, the plot treated with Chitosan solution (${\times}$500) showed higher degradability. In terms of average degradability with time, degradability increased sharply 7 days after the foliar application of testing materials. 3. When the daily far-sighted view survey was conducted in order to find out growth disorder and damage on the Altari radish plants by the treatment of un-derground water, Chitosan solution (${\times}$500), and wood vinegar solution (${\times}$1,000), no symptomatic physiological disorders was observed on all the plants tested during the whole growing season at the tested concentration level.

• Korean Journal of Organic Agriculture
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• v.20 no.3
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• pp.345-356
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• 2012

We conducted a survey of actual using conditions of farm-made liquid fertilizers by investigating their formulation types, materials, making processes, using methods and various beneficial effects on 29 farms certified by National Agricultural Products Quality Management Service to produce environment-friendly agricultural products in 2009. Most of the materials used to make liquid fertilizers are those that can be easily obtained around the farms. Molasses or black sugar are added as an energy source of microorganism. And leaf mold, bacterial cultures supplied by agricultural extension centers of local governments, and cultures of native microorganisms were used as microbial sources for fermenting effective microorganisms. Types of the farm-made liquid fertilizers were fermented liquid fertilizers, fermented plant juices, amino acid liquid fertilizers, calcium-liquid fertilizers, and phosphoric acid liquid fertilizers. Effects of liquid fertilizers used by the farms were found to promote plant growth by supplying nutrition, to accelerate blooming and flower bud formation, to enhance the quality of agricultural products such as increase of sugar contents and improvement of storing conditions, to induce resistance against diseases and insect pests, and to cause endurance to high temperature stress. Chemical properties of the liquid fertilizers collected were analyzed. As a result, pH and EC range showed differences according to kinds of the liquid fertilizers. Amount of macro-nutrients, such as nitrogen and phosphoric acid, in most of the collected liquid fertilizers, was found to be low. Even though the liquid fertilizers were made from same materials, their contents was found to be different depending on the making process.

• Korean Journal of Organic Agriculture
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• v.20 no.1
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• pp.71-80
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• 2012

This experiments was conducted to investigate the influence on growth of rye, triticale with legume and investigated their productivity, feed value and stock carrying capacity in order to select the appropriate forage species in the central region of Korea. In the results, Rye+Red clover showed 5.2ton/ha of dry matter yield. But there was no significant difference with Triticale+Red clover and Rye in upland field. In paddy field, Rye+Hairy vetch showed 5.2ton/ha, but there was no significant difference with Triticale+Hairy vetch and Rye. Mixture effects with Rye, Triticale and Red clover, Hairy vetch by relative yield were more than 1.00 compared to monoculture, and their mixture effect was recognized in upland and paddy field. Relative feed value was highest in the applications of Triticale mixture in upland and paddy field. The average value of $K_{CP}$ and $K_{TDN}$ showed the highest one as 2.75head/ha/yr in Rye+Red clover in upland field and 2.84head/ ha/yr in Triticale+Hairy vetch in paddy field. According to the results, Rye+Red clover in upland field and Triticale+Hairy vetch in paddy field were considered to be the most appropriate winter forage crops for the central region of Korea in terms of productivity, feed value and stock carrying capacity.

• Korean Journal of Organic Agriculture
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• v.20 no.1
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• pp.59-70
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• 2012

This experiments was conducted to investigate the influence on the growth of Sorghum ${\times}$ Sudangrass hybrid by use of various organic fertilizer and investigated their productivity, feed value and stock carrying capacity. In the results, the application of fermented poultry manure showed 93.6ton/ha, 19.6ton/ha, 1.12ton/ha, 11.31ton/ha of fresh yield, dry matter yield, crude protein (CP) yield and total digestible nutrients (TDN) yield but there were no significant differences with the application of poultry by-product compost (poultry manure with sawdust) and swine by-product compost (swine manure with sawdust). And the average value of $K_{CP}$ and $K_{TDN}$ showed the highest one as 9.45head/ha/yr in the application of fermented poultry manure. However, organic matter content of fermented poultry manure to the lower portion of 32.1% compared to other organic fertilizers could imagine that mineralization of fermented poultry manure was fairly advanced and plant used most of nitrogen in fermented poultry manure, so productivity of Sorghum ${\times}$ Sudangrass hybrid was shown more than other organic fertilizers. If other organic fertilizers use continuous, this difference can be considered to be reduced further. As a result, fermented poultry manure is better than other organic fertilizers in productivity, feed value and stock carrying capacity due to the higher content of mineralizable matters. In addition, mixing poultry manure with cow and swine manure is better choice because cow and swine manure will meet a low organic matter in poultry manure.

• Korean Journal of Organic Agriculture
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• v.20 no.1
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• pp.37-48
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• 2012

This study was conducted to evaluate the effects of ground cover treatments on the nutrient contribution in a 'Niitaka' pear ($Pyrus$ $pyriforia$) orchard. Treatments included; 1) sod culture, 2) winter cover crop [ryegrass+hairy vetch], and 3) winter [ryegrass+hairy vetch]+summer [greensolgo (sudan grass ($Sorghum$ $bicolor$ L.))+ nemajanghwang (crotalaria ($Crotalaria$ $juncea$ L.)] cover crops. Ryegrass and hairyvetch were seeded with 6.4 kg/10a and 3.0 kg/10a, respectively, on October 17 of 2008, and greensolgo and nemajanghwang were seeded with 2.0 kg/10a and 3.0 kg/10a, respectively, on June 4 of 2009 at a diligent farmer in Boseong in Chonnam. Winter+summer cover crops provided greater amounts of dry weight, followed by winter cover crop and sod culture. The difference of amounts of dry weight from the ground covers affected to the levels of total N, P, and K contents, which were greater nutrient levels than those of recommended nutrient requirement for satisfying 10- to 12-year-old pear tree growth. Greater amounts of dry weight from the ground covers increased organic matter and concentrations of K and Mg in soil. Foliar nutrient concentrations, as an indicator of nutrient status of a tree, were not affected by application of ground cover treatments.

• Korean Journal of Organic Agriculture
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• v.20 no.3
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• pp.357-368
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• 2012

This study was conducted to evaluate soil inorganic N concentrations and N uptake efficiency of sorghum ${\times}$ sudangrass hybrid (Sorghum bicolor (L.) Moench) as affected by organic nutrient sources from 2009 to 2011. The treatments included chemical fertilizer, compost, oilcake, alfalfa hay mulch, and control. Nutrient applications were made at rates equivalent to approximately 210 kg of actual N per hectare. The precipitation during the growth period from May to September was higher in 2011, followed by 2009, and 2010. Oilcake had the lowest C:N ratio in the raw materials. Compost treatment slowed N-mineralization rate in soil during the measured years. Soil mineral nutrition and dry matter production were not consistently affected by treatments, but the dry matter production was negatively correlated with the amount of precipitation from May to September for three years. Chemical fertilizer treatment increased N efficiency in plants in the first two years, observing with lower N efficiency in plants treated with compost for 3 years. Increased precipitation from June to August improved N efficiency in sudangrass plants treated with compost but reduced the efficiency with the chemical fertilizer. Total dry matter production and N efficiency in plants were not affected by the C:N ratio of the raw materials rather than weather condition.

• Korean Journal of Organic Agriculture
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• v.21 no.3
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• pp.437-450
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• 2013

Miscanthus sacchariflorus var. No. 1 has been newly developed in Korea. This study was conducted to assess the feed value of M. sacchariflorus var. No. 1 at different growth and harvesting time. Total 3 different miscanthus - 1y4m (first shoot and harvested at 4 month), 2y4m (second shoot and harvested at 4 month) and 2y8m (second shoot and harvested at 8 month). Two experiments were carried out, In vitro rumen simulated fermentation and In situ dry matter digestibility (DMD). Ruminal pH at in vitro fermentation were higher in M. sacchariflorus var. No. 1 treatments compared to the rice straw (RS). In volatile fatty acid production, 1y4m resulted in higher acetate production than the other M. sacchariflorus var. No. 1 at higher maturity stages. Significant differences among treatments were observed in propionate and total volatile fatty acid (VFA) productions at 9, 24 and 48 h of incubation times. Higher ammonia nitrogen productions were found as increased maturity of M. sacchariflorus var. No. 1. At In situ experiment, high DMD was detected in the order of RS (60.51%) > 1y4m (57.65%) > 2y4m (57.63%) > 2y8m (46.28%). The results from this study indicate that young and early harvested M. sacchariflorus var. No. 1 are able to improve its nutrient values in the ruminant animal.