• The Plant Pathology Journal
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• 제36권5호
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• pp.398-405
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• 2020

Nutrient manipulation is a promising strategy for controlling plant diseases in sustainable agriculture. Although many studies have investigated the relationships between certain elements and plant diseases, few have comprehensively explored how differing mineral nutrition levels might affect plant-fungal pathogen interactions, namely plant susceptibility and resistance. Here, we systematically explored the effects of the seven mineral elements that plants require in the greatest amounts for normal development on the susceptibility of soybean plants (Glycine max) to Fusarium oxysporum infection in controlled greenhouse conditions. Nitrogen (N) negligibly affected plant susceptibility to infection in the range 4 to 24 mM for both tested soybean cultivars. At relatively high concentrations, phosphorus (P) increased plant susceptibility to infection, which led to severely reduced shoot and root dry weights. Potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), and iron (Fe) induced plant resistance to infection as their concentrations were increased. For K and Ca, moderate concentrations had a positive effect on plant resistance to the pathogen, whereas relatively high doses of either element adversely affected plant growth and promoted disease symptoms. Further experiments were conducted, assessing disease suppression by selected combinations of macro-elements and Fe at screened concentrations, i.e., K (9 mM) plus Fe (0.2 mM), and S (4 mM) plus Fe (0.2 mM). The disease index was significantly reduced by the combination of K plus Fe. In conclusion, this systematic investigation of soybean plant responses to F. oxysporum infection provides a solid basis for future environmentally-friendly choices for application in soybean disease control programs.

• Journal of Microbiology and Biotechnology
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• 제15권6호
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• pp.1273-1279
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• 2005

Penicillium oxalicum strain CBPS-3F-Tsa, an efficient phosphate solubilizing fungus, was evaluated for its production of organic acid in vitro and effect of inoculation on the growth promotion of Maize under greenhouse conditions. The fungus solubilized 129.1, 118.8, and 54.1 mg P/1 of tricalcium phosphate [$Ca_{3}(PO_{4})_{2}$], aluminum phosphate ($A1PO_{4}$),and ferric phosphate ($FePO_{4}$), respectively, after 72 h of incubation. Malic acid, gluconic acid, and oxalic acid were detected in the flasks supplemented with various phosphate sources [240, 146, 145 mM/1 $A1PO_{4},\;FePO_{4},\;and\;Ca_{3}(PO_{4})_{2}$, respectively] together with a large amount of malic acid followed by the other two. The effects of inoculation of P. oxalicum CBPS-3F-Tsa on maize plants were studied under pot culture conditions. P. oxalicum CBPS-3F-Tsa was inoculated to maize plants alone or together with inorganic phosphates in the form of fused phosphates (FP) and rock phosphates (RP). Inoculation of P. oxalicum CBPS-3F-Tsa increased the plant growth and N and P accumulation in plants, compared with control plants, and also had positive effects when applied with RP. The results of this study show that the fungus P. oxalicum strain CBPS-3F-Tsa could solubilize different insoluble phosphates by producing organic acids, particularly malic acid, and also improved the efficiency of RP applied to maize plants.

• 한국농공학회논문집
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• 제60권3호
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• pp.37-50
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• 2018

Local climate characteristics for both urban and rural areas can be attributed to multiple factors. Two factors affecting these characteristics include: 1) greenhouse gases related to global warming, and 2) urban heat island (UHI) effects caused by changes in surface land use and energy balances related to rapid urbanization. Because of the unique hydrological and climatological characteristics of cities compared with rural and forested areas, distinguishing the impacts of global warming urbanization is important. In this study, we analyzed anthropogenic climatic changes caused by rapid urbanization. Weather elements (maximum temperature, minimum temperature, and precipitation) over the last 60 years (1955-2016) are compared in urban areas (Seoul, Incheon, Pohang, Daegu, Jeonju, Ulsan, Gwangju, Busan) and rural/forested areas (Gangneung, Chupungnyeong, Mokpo, and Yeosu). Temperature differences between these areas reveal the effects of urbanization and global warming. The findings of this study can be used to analyze and forecast the impacts of climate change and urbanization in other urban and non-urban areas.

• 임산에너지
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• 제20권2호
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• pp.34-40
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• 2001

본 연구는 IBA(indole-butyric acid) 처리가 7년생 분재 소재용 곰솔의 공중취목 부위의 뿌리 발달과 생장에 어떠한 영향을 미치는 가를 탐구하고자 2000년 4월 13일 및 6월 11일의 2회에 걸쳐 상대습도 조절이 가능한 비닐온실 내에서 실시되었다. 처리 IBA 농도는 대조구, 1000ppm 및 5000ppm의 3 수준이었다. 환상박피 부위에 대한 IBA 처리에 따른 발근 소요일을 보면, 4월 실시 5000ppm에서는 80일로 나타나 대조구 및 1000pprn에 비하여 약 20여일 정도 빠른 것으로 조사되었다. 6월 실시의 경우에는 처리농도에 관계없이 4월 보다 빨라 약 60∼66일이 소요되는 것으로 측정되었다. 4월에 실시된 IBA 처리는 박피 부위에서 발생된 뿌리 수 및 건중량에 영향을 주지 못했으나, 6월에서의 IBA 처리는 대조구에 비하여 장근과 세근의 발생 수 및 뿌리 건중량을 증가시켰다.

• 생물환경조절학회지
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• 제11권2호
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• pp.61-66
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• 2002

포도 시설재배시 년 2기작 재배를 하려면 가장 문제가 되는 것이 여름의 휴면타파에 의한 2차 생장의 유도이다. 본 연구에서는 근권환경조절에 의하여 토양수분조절과 휴면타파제 처리에 의하여 발아율을 높이기 위한 연구를 수행하였다. 근권수분조절에 의하여 신초의 등숙을 7, 8월에 유도할 수 있었다. 근권환경조절에 의하여 1차 생장은 일반 시설재배의 신초생육과 차이가 없었다. 2기작 재배를 위한 휴면타파 처리제는 시아나미드화합물에 메리트청을 혼합한 구가 75% 이상의 높은 발아율을 나타내었다. 신초 등숙 유도를 위한 수분중단구가 수분공급구 보다 발아율이 높았다. 결실 신초율은 처리간 타이가 없었으나 신초발아 시기가 균일하지 않았다.

• 한국응용곤충학회지
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• 제34권1호
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• pp.75-81
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• 1995

시설 과채류 재배지의 뿌리혹선충의 피해경감을 위해서 경북도내 시설 오이 재배단지인 칠곡과 참외재배 주산지인 성주에서 1992년부터 1994년까지 3년간 방제시험한 결과 뿌리혹선충의 피해를 경감시키기 위한 토양개량 적기는 모래산흙인 마사토의 경우에 3년 붉은산흙인 경우 4년마다 하는 것이 효과적이고 농약과 조합한 오이의 방재시험에서 빗사마드 분제가 78.2%, 카보입제+토양반전+담수가 71.2%, 카보입제+담수가 66.3%이었으며 참외에서 살충제처리후 20일에는 77.7~80.6%의 방제효과를 보였으나 60일 후에는 33.7~49.5%로 방제가 낮아 후기에는 효과가 낮았다. 참외재배 논에서의 작부체계에 따른 뿌리혹선충 밀도 억제효과는 참외 재배후 담수하여 벼를 재배할 때에 벼 수확시 방제효과가 91.1%로 대부분의 선충이 사멸되었다. 각 처리구 공히 처리당시에는 뿌리혹선충 증식을 억제하였으나 생육추기로 갈수록 선충밀도가 증가되었다. 그러나 토양개량은 3년간 효과적이였으며 가장 경제적으로 선충의 증식을 억제하 수 있는 처리는 3년마다 한번씩 벼를 재배하는 것이었다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.319-319
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• 2017

Methane is the main greenhouse gas released from rice paddy field. Methane from paddy fields accounts for 11 % of the global total methane emission. The global warming potential (GWP) of methane is 25 times more than that of carbon dioxide on a mass basis. It is well known that most effective practice to mitigate methane in paddy is related to the water management during rice growing season and the use of organic matters. This study was conducted to investigate the effects of tillage and cultivation method on methane emission in paddy. Tillage (tillage and no-tillage) and cultivation methods (transplanting and direct seeding) were combined tillage-transplanting (T-T), tillage-wet hill seeding (T-W), tillage-dry seeding (T-D) and no-till dry seeding (NT-D) to evaluate methane mitigation efficiency. Daily methane emission was decreased on seeding treatments (T-W, T-D, NT-D) than transplanting treatment (T-T). Amount of methane emission during rice growing season is highest in T-T ($411.7CH_4\;kg\;ha^{-1}y^{-1}$) and lowest in NT-D treatment (89.7). In T-W and T-D treatments, methane emissions were significantly decreased by 36 and 51 % respectively compared with T-T. Methane emissions were highly correlated with the dry weight of whole rice plant ($R^2=0.62{\sim}0.93$). T-T treatment showed highest $R^2$ (0.93) among the four treatments. Rice grain yields did not significantly differ with the tillage and cultivation methods used. These results suggest that direct seeding practice in rice production could mitigate the methane emissions without loss in grain yield.

• 한국환경복원기술학회지
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• 제12권2호
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• pp.95-105
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• 2009

Land Use Changes (LUCs) have effects on greenhouse gas emissions and carbon stocks in soil and vegetation. Therefore, predictions for LUC are very important for achieving quantitative targets of $CO_2$ reduction rates. Some research exists on carbon fluxes and carbon cycles to estimate carbon stocks in terrestrial ecosystems in Korea. However, these researches have limitations in terms of helping us understand future potential reductions of $CO_2$ that reflect the influence of LUC. The aim of this study is to analyze the reduction levels of $CO_2$ emissions while considering LUC scenarios that effect carbon fluxes for LCS basic study in the year 2030. In this study, a common approach to model the effects of LUC on carbon stocks is the use of CA-Markov technical process with LUC patterns in the past. Potential reduction of $CO_2$ is calculated by change of land use that contains different soil organic carbon, each land use type, and biomass in vegetation. An IPCC analytical method of natural carbon sink and coefficient results from previous study in Korea is used as a calculation method for potential reduction of $CO_2$. As a result, 12,419 KtC will be reduced annually, which is 8.3% percent of 2005 $CO_2$ emissions in Korea. This will result in 3,226 hundred million won of economic efficiency. In conclusion, conservation of natural carbon sinks is necessary even if the amount of potential reduction change is little.

• Journal of Microbiology and Biotechnology
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• 제23권6호
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• pp.771-778
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• 2013

Essential oils are increasingly of interest for use as novel drugs acting as antimicrobial and antiviral agents. In the present study, we report the in vitro antiviral activities of 29 essential oils, extracted from Chinese indigenous aromatic plants, against the tobacco mosaic virus (TMV). Of these essential oils, those oils from ginger, lemon, tea tree, tangerine peel, artemisia, and lemongrass effected a more than 50% inhibition of TMV at 100 ${\mu}g/ml$. In addition, the mode of antiviral action of the active essential oils was also determined. Essential oils isolated from artemisia and lemongrass possessed potent inactivation and curative effects in vivo and had a directly passivating effect on TMV infection in a dose-dependent manner. However, all other active essential oils exhibited a moderate protective effect in vivo. The chemical constitutions of the essential oils from ginger, lemon, tea tree, tangerine peel, artemisia, and lemongrass were identified by gas chromatography and gas chromatography-mass spectrometry. The major components of these essential oils were ${\alpha}$-zingiberene (35.21%), limonene (76.25%), terpinen-4-ol (41.20%), limonene (80.95%), 1,8-cineole (27.45%), and terpinolene (10.67%). The curative effects of 10 individual compounds from the active essential oils on TMV infection were also examined in vivo. The compounds from citronellal, limonene, 1,8-cineole, and ${\alpha}$-zingiberene effected a more than 40% inhibition rate for TMV infection, and the other compounds demonstrated moderate activities at 320 ${\mu}g/ml$ in vivo. There results indicate that the essential oils isolated from artemisia and lemongrass, and the individual compound citronellal, have the potential to be used as an effective alternative for the treatment of tobacco plants infected with TMV under greenhouse conditions.

• 환경생물
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• 제17권1호
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• pp.11-15
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• 1999

저선량 방사선에 의한 식물 유익효과를 구명하기 위하여 2개 종묘회사로부터 4년간 묵은 종자를 분양받아 저수준의 ${\gamma}$선을 조사하여 온실과 포장에서 재배하여 그 생육 상황을 조사하였다. 서울종묘의 한여름배추는 0.5 Gy 조사구를 제외하고는 발아율 증대효과는 없었고 8 Gy와 12 Gy 조사구에서 유묘초장과 생체중이 각각 평균 20%와 40%정도 증가하여 초기생육 촉진효과는 있었으나 포장수량 증가 효과는 볼 수 없었다. 흥농종묘의 tropic emperor 품종에서는 1 Gy 조사에서 발아율이 10% 정도 증가하였고 유묘초장과 생체중은 1 Gy와 12 Gy 조사구에서 평균 20% 정도 증가하였으며 포장수량에서도 0.5 Gy와 4 Gy에서 초장과 생체중이 각각 10%와 20%정도 증가하였다. 결과적으로 저선량 방사선에 의한 배추의 초기생육 촉진효과가 있는 것으로 사료된다.