• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2004년도 The 2004 KSPP Annual Meeting & International Symposium
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• pp.36-38
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• 2004

Ethaboxam is a new fungicidal active ingredient that inhibits growth of plant pathogens specifically belonging to Oomycetes with protective, curative, systemic and translaminar activity in plants. Modes of action studies revealed that ethaboxam simultaneously inhibits cytoskeleton formation and mitochondrial respiration of Phytophthora infestans at low concentrations. There have been no indications of resistance development when tested for baseline resistance monitoring to 261 isolates of P. infestans in Korea and Europe and 150 populations of Plasmopara viticola populations in Europe for 3 years since 2000. In a selective study with vine trees artificially inoculated with P. viticola repeatedly for 10 generations in greenhouse, there have been no changes in sensitivity to ethaboxam among four natural populations of P. viticola. Furthermore, ethamoxam has not shown any cross resistance with azoxystrobin, mefenoxam, dimethomorph and cymoxanil. Based on the study results from modes of action and resistance development, ethaboxam appears to be unlikely to develop resistance in field applications.

• 한국작물학회지
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• 제52권4호
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• pp.393-402
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• 2007

Remote sensing data can be integrated into crop models, making simulation improved. A crop model that uses remote sensing data was evaluated for its capability, which was performed through comparing three different methods of canopy measurement for cotton(Gossypium hirsutum L.). The measurement methods used were leaf area index(LAI), hand-held remotely sensed perpendicular vegetation index(PVI), and satellite remotely sensed PVI. Simulated values of cotton growth and lint yield showed reasonable agreement with the corresponding measurements when canopy measurements of LAI and hand-held remotely sensed PVI were used for model calibration. Meanwhile, simulated lint yields involving the satellite remotely sensed PVI were in rough agreement with the measured lint yields. We believe this matter could be improved by using remote sensing data obtained from finer resolution sensors. The model not only has simple input requirements but also is easy to use. It promises to expand its applicability to other regions for crop production, and to be applicable to regional crop growth monitoring and yield mapping projects.

• 한국작물학회지
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• 제47권4호
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• pp.283-285
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• 2002

Momilactones A and B, the major phytotoxins and phytoalexins in rice plants, were quantified by a HPLC-APCI-MS-MS (APCI-MS-MS) system under multiple reaction monitoring conditions. Since MA and MB were found to be easily extracted with water, these phytotoxic compounds may affect germination and growth of other plant species when the rice straws were left in the fields.

• Journal of Forest and Environmental Science
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• 제36권3호
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• pp.207-218
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• 2020

Ashwagandha is an important ancient medicinal crops, being affected with many diseases, among which leaf blight caused by Alternaria alternata has become the constraint resulting in huge yield losses. Continuous usage of chemical methods leads to environment, soil and water pollution. Whereas biological control of diseases is long lasting, inexpensive, eco-friendly and harmless to target organisms. In this context, it is aimed to evaluate five Trichoderma strains viz. Trichoderma virens IMI-392430, T. pseudokoningii IMI-392431, T. harzianum IMI-392432, T. harzianum IMI-392433 and T. harzianum IMI-392434 as bio-control efficacy against A. alternata and growth promoting effect in Ashwagandha. All the Trichoderma strains had varied antagonistic effects against the pathogen. In dual culture technique, the strain T. harzianum IMI-392433 showed maximum percentage inhibition of mycelial growth (54.89%) followed by T. harzianum IMI-392432 (53.83%), T. harzianum IMI-392434 (48.94%) and T. virens IMI-392430, (43.62%) against the pathogen, while the least inhibition percentage was observed with the T. pseudokoningii IMI-392431 (36.60%). The culture filtrate of the Trichoderma strain, T. harzianum IMI-392433 recorded highest inhibition on the mycelial growth (39.05%) and spore germination (80.77%) of pathogen and the lowest was recorded in T. pseudokoningii IMI-392431 (20.45 and 50%). Moreover, seeds treated with spore suspension of the strain T. harzianum IMI-392433 reduced the percentages of disease severity index significantly. The strain T. harzianum IMI-392433 also significantly increased seed germination %, seedling vigor and growth of Ashwagandha. The correlation matrix showed that root yield per plant of Ashwagandha had significant and positive correlation with plant height (r=0.726^⁎⁎), number of leaf (r=0.514^⁎⁎), number of primary branch (r=0.820^⁎⁎), number of secondary branch (r=0.829^⁎⁎), fresh plant weight (r=0.887^⁎⁎), plant dry weight (r=0.613^⁎⁎), root length (r=0.824^⁎⁎), root diameter (r=0.786^⁎⁎), root dry weight (r=0.739^⁎⁎) and fresh root weight (r=0.731^⁎⁎). The significant and negative correlation (r=-0.336^⁎⁎) was observed with the root yield and percentages of disease severity index. The study recognized that the T. harzianum IMI-392433 strain performed well in inhibiting the mycelial growth and reduced the percentages of disease severity index of pathogen as well as increased the plant growth in Ashwagandha.

• 한국토양비료학회지
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• 제50권5호
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• pp.409-421
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• 2017

Recently Unmanned Aerial Vehicle (UAV) technology offers new opportunities for assessing crop growth condition using UAV imagery. The objective of this study was to select optimal vegetation indices and regression model for estimating of rice growth using UAV images. This study was conducted using a fixed-wing UAV (Model : Ebee) with Cannon S110 and Cannon IXUS camera during farming season in 2016 on the experiment field of National Institute of Crop Science. Before heading stage of rice, there were strong relationships between rice growth parameters (plant height, dry weight and LAI (Leaf Area Index)) and NDVI (Normalized Difference Vegetation Index) using natural exponential function ($R{\geq}0.97$). After heading stage, there were strong relationships between rice dry weight and NDVI, gNDVI (green NDVI), RVI (Ratio Vegetation Index), CI-G (Chlorophyll Index-Green) using quadratic function ($R{\leq}-0.98$). There were no apparent relationships between rice growth parameters and vegetation indices using only Red-Green-Blue band images.

• 대한원격탐사학회지
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• 제38권6_1호
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• pp.1207-1217
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• 2022

농업의 새로운 패러다임인 디지털 농업에서는 원격탐사 기법을 이용하여 작물 생육을 지속으로 감시하며 상태를 신속히 정보화하고 있다. 대표적으로 작물의 생육·생리적 변화에 대한 선택적인 파장 반사도 변화를 기반으로 한 식생지수가 주로 사용되어진다. 하지만 식생 표면의 분광 반사도는 이방성을 갖기 때문에 태양 위치와 지면 관측 방향에 따라 변할 수 있어 식생지수 값이 작물의 상태를 나타내지 못하고 왜곡될 수 있다. 본 연구에서는 야외용 측각기를 제작하여 타프(tarp)와 잔디 식생에서 시험 운영하였다. 램버시안 표면과 유사한 성질의 타프에서는 Blue, Green, Red, 근적외선 파장에 대해 대체적으로 타프의 속성 반사도와 유사하게 측정되었다. 하지만, 흐린 날은 센서 천정각이 커질수록 반사도가 과대 측정되는 경향을 보였다. 잔디에서 주요 식생지수의 상대 차잇값을 보았을 때, 태양과 센서 천정각에 대해 visible atmospherically resistant index (VARI)와 vegetation index green (VIgreen),simple ratio (SR), normalized difference vegetation index (NDVI), enhanced vegetation index (EVI) 순으로 민감하였다. 측각기를 통해서 직접 관측된 자료들은 원격탐사 기반의 반사도 기반 식생지수를 보다 정확하게 산출하는데 기여할 수 있을 것이다.

• International Journal of Internet, Broadcasting and Communication
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• 제12권1호
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• pp.130-136
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• 2020

There are many problems that occur currently in agriculture industries. The problems such as unexpected of changing weather condition, lack of labor, dry soil were some of the reasons that may cause the growth of the plants. Condition of the weather in local area is inconsistent due to the global warming effect thus affecting the production of the crops. Furthermore, the loss of farm labor to urban manufacturing jobs is also the problem in this industry. Besides, the condition for the plant like air humidity, air temperature, air quality index, and soil moisture are not being recorded automatically which is more reason for the need of implementation system to monitor the data for future research and development of agriculture industry. As of this, we aim to provide a solution by developing IoT-based platform along with the irrigation for increasing crop quality and productivity in agriculture field. We aim to develop a smart garden system environment which the system is able to auto-monitoring the humidity and temperature of surroundings, air quality and soil moisture. The system also has the capability of automating the irrigation process by analyzing the moisture of soil and the climate condition (like raining). Besides, we aim to develop user-friendly system interface to monitor the data collected from the respective sensor. We adopt an open source hardware to implementation and evaluate this research.

• 한국농림기상학회지
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• 제2권1호
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• pp.9-15
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• 2000

날씨ㆍ밤낮에 관계없이 자료를 취득할 수 있는 RADARSAT(C-밴드; 5.3GHz, HH 편광)의 후방산란계수와 태양광에 대한 반사값으로 데이터가 얻어지는 Landsat TM의 자료값(DN; Digital Numbers)을 이용하여 벼 생육과의 관계를 조사하였다. 벼 생육기간 동안 RADARSAT 3시기의 자료를 취득하여 보정 과정을 통하여 지표면의 특성이 잘 나타나는 후방산란계수 (backscatter coefcient)를 산출하였다. 연구지역에서 초장, 엽면적지수, 생체중, 건물중 등 벼의 생육변수를 조사하여 산출된 후방산란계수를 비교하였으며, Landsat TM은 논지역의 6시기 자료값을 산출하여 벼 생육과의 관계를 살펴보았다. 벼의 생육초기 담수상태일 때 논의 후방산란계수 범위는 -22dB--20dB이었고, 벼의 영양생장이 최대에 달했을 때 논의 후방산란계수는 -9dB--8dB 범위로 생육단계별로 뚜렷한 차이를 보였고 생육변수, 초장, 엽면적지수, 생체중, 건물 중 변화와 유사한 경향을 나타내었다 TM 밴드 1, 2, 3의 자료값은 생육후기로 갈수록 낮아졌다가 등숙기에 다시 높아졌고, TM 밴드 4의 자료값은 생육후기로 갈수록 높아졌다가 등숙기에 낮아지는 경향이었다. TM밴드 5와 7의 자료값은 생육기간 동안 계속 증가하여 건물중의 변화추세와 유사하였다. 시계열 RADARSAT과 Landsat TM자료를 이용한 벼 생육모리터링은 전망이 있는 것으로 보인다.

• 한국농공학회논문집
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• 제57권4호
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• pp.113-120
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• 2015

The objectives of this study were to monitor and assess the effects of saline irrigation water on lettuce and carrot growth in protected cultivation. One control and 4 treatments with three replications, which were differentiated according to the level of salinity in irrigated water, were employed for each vegetable to assess the effects of the irrigation with saline water. Monitoring results showed that the use of irrigation water containing above a certain level of salinity was found to cause excessive accumulation of salts in the soil as saline irrigation water increased electrical conductivity (EC) and sodium ($Na^+$) content in both lettuce and carrot soil samples, while tap water irrigation used as control decreased the salinity in the samples. The salinity higher than the threshold level of irrigation water was found to reduce the yields of lettuce and carrot, while in less than the threshold level the higher the salinity of the irrigation water increased the yields. The salinity of the irrigation water also appeared to increase the internal salinity of the plant as the $Na^+$ content in plant increased as the salinity of irrigation water increase. Increased $Na^+$ content was analyzed to be able to increase the sugar content in carrot. This study could contribute to suggest water quality criteria for safe use of saline water in protected cultivation, although long-term monitoring is needed to get more representative results.

• 한국환경농학회지
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• 제34권2호
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• pp.111-119
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• 2015

BACKGROUND: Ethychlozate (ECZ) is a plant growth regulator of synthetic auxin for agricultural commodities (ACs). Accurate and sensitive method to determine ECZ in diverse ACs on global official purpose is required to legal residue regulation. As the current official method is confined to the limited type of crops with poor validation, this study was conducted to improve and extend the ECZ method using high-performance liquid chromatography (HPLC) in all the registered crops with method verification. METHODS AND RESULTS: ECZ and its acidic metabolite (ECZA) were both extracted from acidified samples with acetone and briefly purified by dichloromethane partition. ECZ was hydrolyzed to form ECZA and the combined ECZA was finally purified by ion-associated partition including hexane-washing. The instrumental quantitation was performed using HPLC/ FLD under ion-suppression of ECZA with no interference by sample co-extractives. The average recoveries of intra- and inter-day experiment ranged from 82.0 to 105.2% and 81.7 to 102.8%, respectively. The repeatability and reproducibility for intra- and inter-day measurements expressed as a relative standard deviation was less than 8.7% and 7.4%, respectively. CONCLUSION: Established analytical method for ECZ residue in ACs was applicable to the nation-wide pesticide residues monitoring program with the acceptable level of sensitivity, repeatability and reproducibility.