• 미생물학회지
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• 제50권4호
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• pp.313-318
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• 2014

최근 지구온난화문제와 화석연료 자원의 부족문제로 인해 지속적이고 친환경적인 미세조류 기반 바이오디젤이 주목받고 있다. 본 연구에서는 돈분 액체비료와 농업용 복합비료가 바이오 디젤 생산을 위한 미세조류 영양원으로 활용될 가능성을 확인해 보았다. 혼합 미세조류 CSS (Chlorella spp., Scenedesmus spp., Stigeoclonium spp.) 배양을 위한 영양원은 돈분 액체비료, 돈분 액체비료와 농업용 복합비료의 혼합, 농업용 복합비료이며, 28일간 Small Scale Raceway Pond (SSRP)에서 옥외배양하였다. 그 결과 혼합 실험구의 바이오매스와 지질 생산성은 각각 0.8g/L, 5.8 mg/L/day로 가장 우수한 바이오매스량과 지질 생산성을 보여주었다. 이 연구를 통해 농업용 복합비료와 돈분 액체비료의 혼합액이 미세조류에 안정적인 영양 공급을 하는 영양원으로 활용될 가능성을 확인하였다. 또한, 미세조류 배양단가와 바이오디젤 생산단가를 낮출 가능성도 탐구하였다.

• 농업과학연구
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• 제50권3호
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• pp.437-446
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• 2023

As the interest in sustainable and environmentally friendly agriculture continues to grow, there is a corresponding increase in organic fertilizers utilization. However, studies on ammonia (NH₃) emissions, which are primarily generated in the agricultural sector, by organic fertilizers are lacking. Additionally, the reliance on imported ingredients in the production of organic fertilizers hinders the widespread adoption of organic fertilizers. This study aims to evaluate NH₃ volatilization by incorporating rice husk biochar into organic fertilizers. The study also aims to assess whether domestically produced rice husk biochar can serve as a viable substitute for imported ingredients. Here, the dynamic chamber method was used under controlled conditions. Results show that inorganic fertilizers readily undergo hydrolysis, thereby rapidly generating significant amounts of NH₃, particularly in the initial stages. In contrast, organic fertilizers decompose gradually, leading to relatively long-term NH₃ emissions. The incorporation of rice husk biochar into organic fertilizers demonstrated diminished daily NH₃ emissions compared to those from commercial organic fertilizers, resulting in decreased total NH₃ volatilization. These findings show that the combination of rice husk biochar can reduce NH₃ volatilization and serve as an alternative to imported ingredients for organic fertilizers. The results of this study can be utilized as fundamental information for the assessment of biochar as a potential ingredient for organic fertilizers.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.190-190
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• 2017

Chemical fertilizers have been used to increase crop production and contributed to escaping food shortages. However, excessive use of chemical fertilizers over a long period caused many problems such as environmental pollution and the hampered production potential of the land. Thus, it is necessary to develop eco-friendly bio-fertilizers that can replace the use of chemical fertilizers. Here, we tested the effect of some nitrogen-fixing microorganims on the plant growth promotion. Seventy free-living nitrogen fixing microorganisms were isolated from rhizosphere of crop cultivation fields, streamside soils and sludge in Ansung, Korea. Of them, three strains (NF2-4-1, Yeast; EMM409, Mesorhizobium; Gsoil662, Burkholderia) were selected to be most efficient in the capacity of N-fixing nitrogen based on colony forming cell assay in N-free media. To investigate the ability to promote plant growth, these strains were inoculated into the soil and cabbage were grown for 4 weeks in the grown chamber. Fresh weight, dry weight, and leaf area were measured from 4-week-old plants. Phenotypic analysis revealed that the growth of the plants inoculated with NF2-4-1 and EMM409 strains were significantly promoted compared to the mock-treated control plants, while Gsoil662-inoculated plants did not show statically significant promotion. These results indicate that these nitrogen-fixing microorganims can be used to develop plant growth promoting bio-fertilizers. Further analysis on nitrogen fixing level in soil by these strains will be tested.

• 농업과학연구
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• 제50권2호
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• pp.231-239
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• 2023

Ammonia (NH₃) emitted from the use of fertilizers during agricultural practice generates particulate matter and odors. The application of carbonized rice husk, an eco-friendly material, is one of the measures used to reduce NH₃. The objective of this study was to evaluate the effect of the application rate and pH of carbonized rice husk on NH₃ emissions and soil quality. An experiment to assess NH₃ emissions was performed in a glasshouse using a static chamber method. The pH of the carbonized rice husk was divided into acidic, neutral, and basic groups, and the carbonized rice husk application rates were 1, 3, and 5% of the soil weight. NH₃ emissions showed a sharp increase within three days after the inorganic fertilizer was applied. Subsequently, NH₃ emissions decreased rapidly after basal fertilization compared to primary and secondary top-dressing. When carbonized rice husks were applied to soil, NH₃ emissions decreased in all treatments, and neutral carbonized rice husk was the most effective in comparison with acidic and basic carbonized rice husk. The application rate of carbonized rice husk and NH₃ emissions showed a negative correlation, and the lowest emissions were found in units with a 5% application rate. Also, there was no statistically significant difference between NH₃ emissions according to the application rate of carbonized rice husk, and when carbonized rice husks were applied at a 5% rate, soil OM increased excessively. Therefore, it is recommended to apply only 1% neutral carbonized rice husk to most effectively reduce NH₃ emissions in the soil.

• 한국토양비료학회지
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• 제45권1호
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• pp.9-15
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• 2012

This study was performed to produce basic data for silty reclaimed tidal lands and to develop techniques of environmentally-friendly utilization in agricultural system. We chose the two sites in Saemangeum reclaimed tidal lands, one (Site I) has been treated with cultivating green manure and conducting the desalinization process through submergence since April, 2007 and the other (Site II) has been under natural condition without artificial treatment. In situ and ex situ physic-chemical properties were determined and comparisons were made for soil profiles examined at these two sites in April 2009. Surface soil of Site I had lower EC and higher field saturated hydraulic conductivity than those of Site II, uncultivated land. Especially, exchangeable sodium content was lowest in Site I Ap1 layer than in other layers. This is probably due to flooding desalination and green manure cultivation. Besides, Ap1 and A2 layers of soil profile in Site I showed brighter soil color and more root observation than those of Site II. This is probably due to green manure cultivation. By the large, for high cash upland crops and intensive agricultural use of silty reclaimed tidal land, site-specific soil ripening such as flooding desalination and green manure cultivation could be useful.

• 한국토양비료학회지
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• 제47권4호
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• pp.275-283
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• 2014

The ${\gamma}$-oryzanol, ferulic acid esters, which are well-known for their function on cholesterol lowering and prevention of inflammation, diabetes and cancer, are found in the seeds of cereal crops such as rice, corn, wheat and rye. Among them, rice has been reported to contain the highest ferulic acid esters. Since rice cultivation with green manure as a N source is an environmental friendly agricultural practice, it is necessary to identify and quantify as well as evaluate the variations in these compounds in rice samples as affected by different green manure conditions. A total of ten components of ${\gamma}$-oryzanol were isolated and cycloartenyl ferulate, 24-methylenecycloartanyl ferulate, campesteryl ferulate and sitosteryl ferulate were identified as the major components in Korean rice cultivars, 'Unkwang' and 'Hopum'. Comparing the ${\gamma}$-oryzanol contents of these varieties, 'Unkwang' showed clearly similar pattern with conventional type. With the PLS-DA (partial least squares of discriminant analysis) using SIMCA 11.0 ver., the specific pattern and cluster of ${\gamma}$-oryzanol scores with green manure conditions were confirmed, and thus distinguishing green manure effects were possible.

• 현장농수산연구지
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• 제10권1호
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• pp.29-41
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• 2008

This research was conducted to develop a technology transfer and farmer's extension of newly released technology of Bokto seeding method for crop and vegetable production based on the theory of Asian and Pacific Center for Transfer of Technology(APCTT). This technology has recently transferred to not only Korea but also other countries like North Korea, China, Japan, Taiwan, Russia and Africa(Cameroon, Sudan and South Africa) since 2005. It has known as a highly reduction of production cost in terms of labors, chemical fertilizer and pesticides as well as environmental friendly due to a deep and side banded placement of chemical fertilizer at basal application. In addition this technology was proven to a precision farming on sowing depth and mechanism of chemical application method and also highly resistant against disasters like typhoon, flooding, low temperature, drought and lodging due to silicate application. It has improved a constraints such as a poor seedling establishment, weed occurrence, lodging, low yield and poor grain and eating quality in the previous direct seeding methods but still have a problem in occurrence of weedy rice and ununiformed operation of wet or flooded soil condition. Also this technology has a limit in marketing and A/S system. Based on a theory of APCTT evaluation and analysis this technology may be more concentrated on establishment of a special cooperation team among researcher and scientists, extension workers, industry sections and governmental sectors in order to rapidly transfer this technology to farmer's field. Also there will be needed to operate a web site for this newly released technology to inform and exchange an idea, experiences and newly improved information. A feed back system might be operated in this technology as well to improve a technology under way on users' operation. Also user's manual will be internationally released and provided for farmer's instruction and training at field site.

• 농업생명과학연구
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• 제50권1호
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• pp.1-22
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• 2016

본 연구에서는 농업 분야 유용미생물 자원의 국가적 확보 현황을 파악하기 위해 이들의 생물분류학적 정보를 수집하였으며 이들에 대해 생물 종 다양성 지수를 도입하여 평가하였다. 대표적인 생물다양성 평가방법인 Margalef's richness 및 Mehinick's index를 각각 적용한 경우 세균은 각각 8.537, 3.546, 진균은 각각 3.349, 2.167의 값을 나타내었다. 높은 수준의 다양성을 가지고 연구·개발되고 있는 이들 농업 분야 유용미생물 및 농산물의 수확 후 선도저하를 유발한다고 보고된 주요 미생물들의 분류학적 위치를 비교하였을 때 일부 미생물이 유사한 분류학적 위치를 보이는 것이 확인되었다. 따라서 친환경농업 분야 유용미생물의 연구개발 및 작물 내생 미생물에 관한 연구 등 농업 분야 미생물에 대한 전반적인 연구현황을 고찰하여 농산물의 수확 후 선도관리를 위한 보완책을 제시하고자 하였다.

• The Plant Pathology Journal
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• 제21권3호
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• pp.270-274
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• 2005

The aim of this study was to determine the effect of milk as one of the environmental friendly materials that substitute chemical fungicides for control powdery mildew (Sphaerotheca aphanis) of strawberries $(Fragaria{\times}ananassa\;Duch.)$. 'Maehyang' and 'Akihime' varieties planted in greenhouses were evaluated for the control of powdery mildew. Applications of $5\%,\;10\%\;and\;20\%$ milk had much better effects on controlling powdery mildew. In particular, $10\%$ milk showed a higher efficacy than other concentrations applied onto straw­berry in greenhouse experiments. Foliar spray application of $10\%$ milk was effective for powdery mildew, whereas drench application was not. Also, foliar spray of $10\%$ milk was able to accelerate more firmness and calcium contents of strawberry fruits than the non-treated. The $10\%$ milk applied with fertilizer salts $(Ca(H_2PO_4)_2-H_2O\;and KH_2PO_4)$ showed there was a similar efficacy to $10\%$ milk alone in greenhouse experiments. White crystals and cracks on strawberry fruits appeared by $20\%$ milk. This result indicated that $10\%$ milk was a useful substitute for fungicides to control powdery mildew of strawberry.

• 한국습지학회지
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• 제20권4호
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• pp.304-313
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• 2018

새만금 간척지의 농지 간척 사업은 대부분 2020 년까지 완공 될 예정이며, 그 시기 토지의 관개용수 활용에 대한 대비가 필요한 실정이다. 그러나 관개수의 수질은 드물게 목표 농도를 충족하고 있다. 이에 본 연구에서는 논에서의 최적관리기법(BMPs)인 토양검정시비(SO#1), SO#1과 SO#3의 복합처리(SO#2), 배수물꼬(SO#3), 완효성 비료시비 (SO#4) 방법을 관행재배(CT: Control)와 비교하여 논 비점오염원 저감효과 및 정책개발 시의 고려사항을 기술하였다. 논에서의 유출 저감은 SO#3(25%)와 SO#1(27%)에서 관행재배와 비교하였을 때 상대적으로 높았으나, SO#4(9%)와 SO#2(7%)에서 낮게 나타났다. 논 유출량의 NPS 오염물질 농도와 부하는 변화의 폭이 높게 나타났으며 BMPs 중에 유의한 차이는 나타나지 않았다. 또한 농민들의 인식조사 결과, 농민들은 실제 BMP 구현의 한계로 기존 관행적인 영농활동을 유지하고 있는 것으로 나타났다. 따라서 NPS 오염물질 관리와 관개수 절약을 위해서 농민 교육 및 지원과 함께 관개물꼬 및 논의 담수심을 자동 조절할 수 있는 관리방안이 필요할 것으로 판단된다.