• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2009.12a
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• pp.310-311
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• 2009

농업현장에서 활용되는 농업용미생물의 효능을 평가하고 현장실용화를 제고할 목적으로 본 시험을 수행하였다. 8개 지자체를 대상으로 친환경농업 특성화 지원사업 현황을 조사하고, 지자체별 미생물 활용수준을 평가하였으며, 각 지자체별로 활용되는 미생물을 수집하여 항균활성, siderophore 생성, IAA 생성, 질소고정, 인산가용화 능력 및 작물생육에 미치는 영향을 분석하였다. 지자체에서 활용하는 미생물은 주로 유산균, 고초균, Bacillus속 세균, 광합성균, 효모 및 EM 등으로 몇가지 종류의 미생물을 활요하는 것으로 조사되었고, 배양을 위한 배지는 대부분 균주를 개발한 대학 또는 산업체에서 공급받는 것으로 나타났으며, 배양기술 측면에서 볼 때 단순 배양 보급하는 지자체가 2개소, 산-학-연간 공급네트워크 및 대량배양체계를 구축하여 미생물을 활용하는 지자체가 7개소, 미생물 대량배양체계를 구축하고 병해충 관리연구를 수행하는 지자체가 1개소 그리고 미생물 선발, 특성검정 및 효과 평가 등 개발 및 응용을 추진하는 지자체가 1개소인 것으로 나타나 지자체에 따라 활용기술 수준은 큰 차이를 보였다. 지자체 공급 농업미생물의 항균활성을 조사한 결과, 고초균, 효모, 유산균, 광합성균, Bacillus속 세균 모두에서 균주에 따라 항균활성을 보였는데, 특히 Bacillus 속 세균이 높은 빈도로 황균활성을 보이는 것으로 나타났다. 철 킬레이트 능력 (Siderophore 형성능)에 있어서는 5개 광합성 균주 중 1균주가, 5종의 효모 중 1균주만이 활성을 보인 반면, Bacillus속 세균(고초균 포함)의 경우에는 11개 균주 모두 활성을 보였다. 작물 생육과 밀접한 관계가 있는 IAA(Indole acetic acid)의 생성능에 있어서는 광합성균이 5균주 중 4균주가 활성을 보여 비교적 생성능이 높은 것으로 나타났으며, Bacillus 속 세균의 경우에는 11균주 중 8개 균주가 활성을 보여 광합성균 다음으로 높은 반도를 나타냈다. 효모의 경우에는 5균주 중 1개 균주가 IAA를 생성하는 것으로 나타났다. 질소고정능에 있어서는 광합성균은 5균주 중 3균주, Bacillus 속세균 11균주 중 6균주가, 효모는 5균중 1균주가 활성을 보인 반면, 유산균 중에는 단 한 균주도 질소 고정능을 보이지 않았다. 연작재배에 따라 토양 내에 축적되는 인산의 가용화능을 분석한 결과, 수집한 대부분의 유산균은 높은 활성을 보인 반면 기타 미생물은 인산가용화능이 거의 없는 것으로 나타났다. 결론적으로 Bacillus 속 세균은 항균활성이 높고, 작물생육과 밀접한 IAA 생성 및 질소고정능력을 보유 하고 있는 것으로 나타나 친환경 작물재배시 병 발생을 줄이고 작물생장을 촉진할 수 있는 미생물로 평가되었다. 농업현장에서 기능성 및 효능을 고려하여 미생물을 잘 활용하면 병 발생 관리 및 생산성 향상에 도움이 되리라 판단된다.

• Korean journal of applied entomology
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• v.47 no.3
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• pp.237-248
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• 2008

Development of T. urticae was studied on the leaves of eggplant grown in hydroponics with nitrogen contents of 5 mM, 10 mM, 30 mM, and 60 mM. As the nitrogen level in hydroponics increased, it also increased in the plant whereas that of K, Ca, and Mg decreased. More nitrogen in hydroponics resulted in increased contents of water and crude protein, and decreased ash, carbohydrates, and fibers within the plant. Biomass was the heaviest as 989.5 g at 10 mM and the lightest at 60 mM. Leaf thickness and the content of chlorophyll increased as the content of nitrogen increased. Laboratory leaf disc tests obtained from plants grown at various nitrogen levels revealed that feeding and oviposition preferences of T. urticae were high at 30 mM and low at 5 mM. Ratio of damaged leaf by naturally occurring T. urticae on eggplants of 99 days post-transplant in the greenhouse was the highest as 98% at 60 mM. Degrees of damage on eggplants with and without T. urticae infestation turned up more as the differences in the levels of nitrogen in the hydroponics get bigger. No definite differences in the rate of T. urticae development was found between nitrogen treatment levels but, mortalities in immature stages dropped as the nitrogen levels went up. Adult longevity was the longest of 11.9 for female and 6.9 days for male at 60 mM. Oviposition period was also the longest as 11.7 days at 60 mM and shortened as the level of nitrogen decreased. The number of eggs oviposited was the most as 144.4 at 60 mM while it was the least as 41.0 at 5 mM. Sex ratio was 0.75 in favor of female at 10 mM. $R_o$ and T increased, no trends were detected in $r_m\;and\;{\lambda}$, while Dt decreased as the levels of nitrogen went up.

• Korean Journal of Environmental Agriculture
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• v.16 no.4
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• pp.394-398
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• 1997

Changes of nutrient material and heavy metals of irrigation water and natural supplies by irrigation water into 1.0ha of paddy field during the rice cultivation was investigated pH of irrigation water ranged 6.458.34 and electrical conductivity showed $110{\mu}S/cm$ in the first irrigation period and commonly showed $90{\mu}S/cm$. The content of T-N, NH4-N and $NO_3-N$were 3.09~12.36, 0.17~1.34 and 2.70~10.72mg/L respectively. The content of T-P was 0.09~0.22mg/L and ortho-P was not detected. The content of $Ca^{++},\;Mg^{++},\;Na^+\;and\;K^+$ showed 0.89~5.12, 1.12~2.76, 1.74~4.52 and 1.34~4.18mg/L regardless of irrigation season respectively. Only Cu and Zn of heavy metals were detected 0.001~0.009 and 0.007~0.091mg/L, but Pb, Cd, Cr and Ni were not detected When supplied $4,250m^3$ of an irrigation water into 1.0㏊ of paddy field, natural supplies of nutrient materials were 29.67㎏ of T-N, 1.80㎏ of $NH_4-N$, 24.57kg of NO3-N and 0.51kg of T-P. Also $Ca^{++},\;Mg^{++},\;Na^+,\;K^+,\;Cl^-\;and\;SO_4\;^{2-}$ were supplied 9.42, 7.09, 13.34, 9.08, 40.27 and 41.38kg respectively. Only Cu and Zn of heavy metals were supplied 0.017kg of Cu and 0.133kg of Zn, Pb, Cd, Cr and Ni were not supplied

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.4
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• pp.292-301
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• 2001

The objectives of this study were to measure the changes in soil moisture regimes and the distribution patterns of inorganic N derived from the fertigated $^{15}N$-labeled urea, and compare them with the results obtained from broadcast-applied soil under the same drip irrigation domain. In fertigated soil, a $^{15}N$-labeled urea solution of $117mg\;N\;L^{-1}$ was applied by surface drip irrigation for 4 weeks. In broadcast-applied soil, no the other hand, 4 g of $^{15}N$-labeled urea(1.87 g N) mixed thoroughly with 5 kg of soil was placed on the surface of packed soil. Soil water status was controlled by drip irrigation scheduled at soil matric potential of -50 kPa. A calibrated time-domain reflectometry probe was installed in the soil vertically 15 cm apart from a drip emitter to control drip irrigation. About 60% of urea-derived inorganic nitrogen was remained in the top zone between 0 and 10 cm depth of fertigated soil, while, most of the inorganic nitrogen (91%) was accumulated in the top zone of broadcast-applied soil. Of inorganic nitrogen derived from urea, the percentage of $NO_3{^-}$ was much higher for fertigation (99%) than for surface application (62%). The relatively lower recovery of urea-derived inorganic nitrogen of broadcast-applied urea-N (51%) than that of fertigated urea-N (89%) was attributable to enhanced $NH_3$ volatilization.

• 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.

• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.1
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• pp.11-16
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• 1999

This study was conducted to compare the dry matter intake, the digestibility, and utilization of nitrogen and energy of Korean native goats, when fed on orchardgrass(OG) mixed with alfalfa(AA) at a different levels. Experimental diets include three treatments : OG 100%, OG 80%+AA 20%, and OG 60%+AA 40%. With increasing levels of AA supplementation, the content of CP was higher for AA supplemented diets than for OG 100% diets, while the content of NDF, ADF, hemicellulose and lignin content were slightly lower for AA supplemented diets than for OG 100% diets. Also, the DM intake and the digestibility of DM, cellular constituents, NDF and ADF were higher for AA supplemented diets than for OG 100% diets, especially those were the highest in OG 60%+AA 40% diets(P<0.05). The apparently digested N, retained N and biological value of AA supplemented diets were increased with increasing levels of AA supplementation, compared with those of OG 100% diets(P<0.05). The utilization of DE and ME were slightly high in OG 60%+AA 40% diets, but there was no significant difference among all diets. According to the results, DM intake, digestibility and nitrogen utilization were improved in goat fed diets with supplementation AA(AA 20%, 40%), compared with those of OG 100% diets. But energy utilization did not show the difference among diets. Hence, It needs to provides to the adequate energy sources to goats.

• Korean Journal of Environmental Agriculture
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• v.31 no.1
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• pp.1-8
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• 2012

BACKGROUND: Organic fertilizers in watermelon cultivation are widely used to supply nutrient and organic matter. This study was conducted to investigate the effects of application rate of organic fertilizer on the watermelon growth and soil chemical properties in greenhouse METHODS AND RESULTS: The organic fertilizers used in this experiment were mixed expeller cake (MEC) and mixed organic fertilizer (MOF). The treatments were conducted with 4 levels (1.0 N, 0.7 N, 0.5 N and 0.3 N) on the basis of soil testing nitrogen fertilization (STNF) using MEC or MOF as the basal dressing, and using chemical fertilizers (CF) as the additional dressing on the rest of STNF. These fertilizations were compared to CF 1.0 N (0.3 N as the basal and 0.7 N as the additional dressing) and non fertilization (NF). The leaf area of watermelon in treatment 0.5 N and 0.3 N using MEC or MOF was similar to CF treatment. The absorbed nutrient amounts by leaf, weight and sugar contents of fruit in the 0.5 N and 0.3 N treatments were higher than other treatments. In 0.5 N and 0.3 N treatments using MEC or MOF on the basis of STNF, soil chemical properties such as electrical conductivity (EC), available $P_2O_5$ and exchangeable K concentrations after experiment showed tendency to decreasing or similar level before experiment. CONCLUSION(s): These results suggest that the MEC or MOF application as the basal dressing at the 30~50% level of STNF and CF application as the additional dressing on the rest of STNF be best to maintain adequate nutrient of soil and to increase marketable yield for watermelon.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.5
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• pp.318-324
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• 2000

Field experiment was conducted on a sandy clay loam paddy field in the Experimental Farm of the Kangwon National University for four years from 1995 to 1998 to evaluate the effect of different nitrogen fertilizers on soil property and rice yield. The size of each experimental plot was 75 m2. Basal application of fertilizer to the paddy field was on late April, and rice (cv. Odae) was sown with drill seeding on early May. Irrigation was done at 3 leaf stages after rice seeding. Electrical conductivity in soils treated with phosphate- and resin coated slow release fertilizers were relatively greater than those of the other fertilizer application. Available $P_2O_5$ concentration in soils after rice harvest increased significantly compared that in soil before field trial. Rice yield in transplanting culture were $6.516kg\;ha^{-1}$. The rice yield in the direct seeded paddy was 81.9 percents of the yield in the transplanted paddy. The rice yield in phosphate coated slow release fertilizer was the highest among various fertilizer trials in directly seeded dry paddy, while rice yield was the lowest in the organic fertilizer plus urea application. Rice yield between organic fertilizer plus urea and organic fertilizer application were not significantly different. The green manuring effect of rye in the direct seeded rice paddy in Chuncheon was low due to low temperature and short growth period.

• Journal of The Korean Society of Grassland and Forage Science
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• v.20 no.3
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• pp.199-206
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• 2000

This experiment was conducted to evaluate the effect of winter forage rye and green manure hairy vetch on soil mineral nitrogen and corn nitrogen uptake. Soil nitrate at corn seeding decreased slightly with cultivation of winter rye, but soil nitrate did not decreased by cultivation of winter hairy vetch. Soil nitrate nitrogen increased 60~70 kgN/ha higher by hairy vetch green manure than winter rye and fallow at 6-leaf and harvest stage of corn, respectively, and much soil nitrate nitrogen such as 85, 125 kgN/ha was remained at N fertilizer 100, 200 kgN/ha of hairy vetch green manure at harvesting time, respectively. Corn yield was not different among treatments of winter crop and N rate, but nitrogen concentration of corn stover increased by hairy vetch green manure. Increase of total corn nitrogen uptake by hairy vetch green manure was 50~60 kgN/ha compared with winter rye and fallow. It is thought that basal fertilizer nitrogen 100 kgN/ha could be reduced by hairy vetch green manure in considering soil nitrate and nitrogen uptake at harvesting time.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.650-658
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• 2010

We used green manure crops such as hairy vetch, crimson clover, rye, sorghum, and sudan grass by mixing with soils to assess the effects of green manure crops on nutrient supply and soil quality improvement. Temporal changes in soil inorganic nitrogen, carbohydrate, microbial biomass, and humus content were determined as soil quality indicators. Inorganic nitrogen content of the control maintained similar level during the whole period, but it had continually increased until 4 weeks after incorporation (WAI) of green manure crops. Especially, inorganic nitrogen content sharply increased in sudan grass. After incorporation of green manure crops, temporal change of soluble sugar in soils was as follows: it had gradually increased in legume green manure crops-incorporated soils until 7 WAI, which was the highest, and then showed the tendency to be reduced. Meanwhile, it in non-legume green manure crops-incorporated soils rapidly increased after the incorporation, and reached the maximum around 4 WAI. Humic acid by the decomposition of crop residues in green manure crops-incorporated soils was greatly enhanced with the elapsed time of 4 WAI, although it was low at the same level as the control until 2 weeks. In addition, there was a difference in fulvic acid by incorporated crops, fulvic acid in hairy vetch, sorghum and sudan grass showed a similar tendency with the change in humic acid. Our results suggest that soluble sugar, microbial activity and humic acid could be available indicators to evaluate the fertility of green manure crops-incorporated soils.