• 대한원격탐사학회지
• /
• 제34권4호
• /
• pp.681-692
• /
• 2018

This study was performed to select the significant wavelengths for predicting the chlorophyll content of grafted cucumber seedlings using hyperspectral images. The visible and near-infrared (VNIR) images and the short-wave infrared images of cucumber cotyledon samples were measured by two hyperspectral cameras. A correlation coefficient spectrum (CCS), a stepwise multiple linear regression (SMLR), and partial least squares (PLS) regression were used to determine significant wavelengths. Some wavelengths at 501, 505, 510, 543, 548, 619, 718, 723, and 727 nm were selected by CCS, SMLR, and PLS as significant wavelengths for estimating chlorophyll content. The results from the calibration models built by SMLR and PLS showed fair relationship between measured and predicted chlorophyll concentration. It was concluded that the hyperspectral imaging technique in the VNIR region is suggested effective for estimating the chlorophyll content of grafted cucumber leaves, non-destructively.

• Journal of Biosystems Engineering
• /
• 제38권4호
• /
• pp.318-326
• /
• 2013

Purpose: We developed a viability evaluation method for cucumber (Cucumis sativus) seed using hyperspectral reflectance imaging. Methods: Reflectance spectra of cucumber seeds in the 400 to 1000 nm range were collected from hyperspectral reflectance images obtained using blue, green, and red LED illumination. A partial least squares-discriminant analysis (PLS-DA) was developed to predict viable and non-viable seeds. Various ranges of spectra induced by four types of LEDs (Blue, Green, Red, and RGB) were investigated to develop the classification models. Results: PLS-DA models for spectra in the 600 to 700 nm range showed 98.5% discrimination accuracy for both viable and non-viable seeds. Using images based on the PLS-DA model, the discrimination accuracy for viable and non-viable seeds was 100% and 99%, respectively Conclusions: Hyperspectral reflectance images made using LED light can be used to select high quality cucumber seeds.

• 수산해양기술연구
• /
• 제50권2호
• /
• pp.202-213
• /
• 2014

The sea cucumber, Apostichopus japonicus, is becoming an important aquaculture species in China, Japan and Korea. The purpose of this study is to evaluate the biological performance of a tubular type of subsurface cage for sea cucumber grow-out by in-situ tests. The cage structure was constructed of PP (polypropylene) frames and PP tubes (${\phi}130mm{\times}24pieces$). A set of tests were conducted at a depth of 15 m near Seosaeng, Ulsan, Korea for 295 days (23 July, 2012 to 13 May, 2013). A total of 155 sea cucumbers were used and fed a mixed diet containing mud, mineral, wheat, fish meal, etc (3% of their body weight). At the end of the experiments, sea cucumber showed a higher survival rate in feed shelter (77.14%) rather than no feed shelter (64.71%). The specific growth rate (SGR) of sea cucumbers in feed condition (0.04% $day^{-1}$) was higher than that of no feed culture animals (-0.49% $day^{-1}$) during total experimental periods. The result was able to find a no significance difference in survival rate but a significance difference in SGR under feed and no feed treatments.

• 한국환경농학회지
• /
• 제23권4호
• /
• pp.191-196
• /
• 2004

The contribution of plant nutrition status in arbuscular mycorrhizal (AM) plant to the nutrient acquisition by extraradical hyphae of AM fungi was investigated using cucumber colonized with Glomus intraradicies (BEG 110) focusing on the Zn. Compartmentalized pots with separated Bones for hyphal growth were used to determine the contribution of extraradical AM hyphae to Zn uptake from hyphal zones. $0.5\;{\mu}M$ Zn was supplied into the hyphal zones as nutrient solution (10 mL/day) with a form of $ZnSO_4$. Zn foliar application was made two times for one week before harvest (8 mL/plant). The colonization rate by AM were high in all of Zn treatments. The dry weight of cucumber increased by AM colonization compared to those of non-mycorrhizal counterpart. However: Zn foliar application resulted in no significant difference in dry weight between mycorrhizal- and non-mycorrhizal plant. In addition, the enhancement of Zn content in cucumber shoot by AM colonization were also reduced by Zn foliar application. These results indicate that the interaction between host plant and AM fungus for nutrient uptake might be related to plant nutritional status and nutrient contents. In consequence, higher Zn contents in host plant by foliar application of Zn could restrict the role of extraradical hyphae of AM fungus on the Zn acquisition and transfer from fungus to host plant.

• 한국응용곤충학회지
• /
• 제41권3호
• /
• pp.211-216
• /
• 2002

박과 작물에 주로 발생하는 목화바둑명나방에 대하여 여러 기주식물들이 생물학적으로 미치는 영향에 관하여 조사하였다. 식이와 산란선호도는 오이와 호박이 수박, 참외, 멜론보다 높게 나타났다. 알과 유충기간은 수박과 오이에서 참외, 멜론과 호박에서 보다 더 짧았다. 번데기 기간은 수박, 멜론, 호박, 참외에서 오이보다 짧았다. 부화율은 오이에서 87.2%로 가장 높았고 멜론에서 72.8%로 가장 낮게 조사되었다. 용화율은 수박과 참외에서 각각 90.0%, 89.1%로 62.0%인 오이에서 보다 높았으며, 우화율은 오이와 호박에서 각각 93.5, 92%로 78.7%인 참외에서 보다 높게 조사되었다. 그리고, 부화에서 우화까지의 생존율은 수박에서 76.0%로 가장 높았으며 오이에서 50.0%로 가장 낮았다. 성충기간은 오이에서 15.5일로 가장 짧았고 멜론에서 21.0일로 가장 길었다. 암컷 한마리당 평균 산란수는 오이에서 281.8개로 가장 많았으며 참외에서 96.6개로 가장 적었다. 그리고, 암컷 성충의 생존기간은 오이에서 30.0일로 가장 길었으며, 호박에서 17.0일로 가장 짧게 나타났다. 산란전기간은 수박에서 2.1일로 짧았고, 참외와 멜론에서 3.4일로 길었다. 그리고 1세대에 요하는 평균기간(T)은 오이에서 41.30일로 가장 짧았지만, 다른 기주식물들과 유의성 있는 차이는 없었다. 1 세대당 순증식율(R$_{o}$ )은 오이에서 191.3으로 가장 높았으며, 내적자연증가율(r$_{m}$ )도 오이에서 0.127로 다른 기주식물들보다 높게 나타났다. 결과적으로 각기 다른 기주식물을 섭식한 목화바둑명나방의 생명표 분석을 통하여 나타났듯이, 이 곤충의 증식에 적합한 기주식물은 오이와 호박인 것으로 나타났다.

• 한국농공학회:학술대회논문집
• /
• 한국농공학회 1998년도 학술발표회 발표논문집
• /
• pp.224-229
• /
• 1998

This study was conducted to develop the simple and convenient irrigation control model which can maintain the appropriate rates of irrigation and drainage of nutrient solution according to the environmental conditions and growth stages in soilless culture of cucumber. In order to obtain fundamental data for development of the model, investigation of the actual state of soilless culture practices was carried out. Most irrigation systems of soilless culture were controlled by the time clock. Evapotranspiration of cucumber in soilless culture was investigated and correlations with environmental conditions were analyzed, and its prediction model was developed. A irrigation control model based on the time clock control and there were considered seasons, weather conditions, and growth stages was developed. Applicability of the model was tested by simulation. Drainage rates of irrigation system controlled by conventional time clock, integrated solar radiation, and the developed model were 61%, 20%, and 32%, respectively in cucumber perlite culture.

• 한국식물병리학회:학술대회논문집
• /
• 한국식물병리학회 1997년도 Proceedings of special lectures on Recent Research Trend of Plant Pathology
• /
• pp.47-55
• /
• 1997

Plant growth promoting fungi(PGPF) obtained from zoysiagrass rhizosphere offer dual advantages - induse systemic disease resistance response in cucumber to C. orbiculare infection and cause enhancement of plant growth and increase yield. PGPF protected plants either by colonizing roots or by their metabolites. PGPF offer an advantage by protecting plants for more than 9 weeks and 6 week in the greenhouse and field. PGPF-induced plants limited pathogen spore germination and decreased the number of infection hyphae on the leaf, and increased lignification at places of attempted pathogen infection, thus reducing the pathogen spread. PGPF elicited increased activities of chitinascs, glucanases, peroxidase, polyphenol oxidase, and phenylalanine ammonia lyase to C. orbiculare infection in cucumber plants. The role of PGPF in elevating cucumber defense response to pathogen infection suggests potential application of PGPF as biological control agents.

• 식물병과 농업
• /
• 제5권1호
• /
• pp.14-19
• /
• 1999

Cucumber mosaic cucumovirus (CMV) is an isometric plant virus with functionally divided genomic RNAs and a broad host range. RNA 1 and RNA 2 each encode one protein, both of which are essential for replication. RNA 3 encodes the viral coat protein and an additional protein thought to be involved in potentiating the cell-to-cell movement of the virus. Functions of the RNAs have been confirmed using a pseudorecombinant virus constructed with infectious cDNA-derived transcripts of the RNAs. Generally, CMV produces different symptoms in various host plants depending on the virus strains. In this mini-review, we describe the potential role of the genes associated with symptom expression of CMV RNAs.

• 한국식물병리학회지
• /
• 제14권1호
• /
• pp.46-51
• /
• 1998

A method for inoculum production of Botryosphaerisa dothidea was developed using cucumber disks and cereal media. Disks of cucumber fruits, and cereal media of barley, wheat, and rice seeds were inoculated with mycelial plugs of B. dothidea and incubated at 27$^{\circ}C$. Pycnidia were produced on the surface of cucumber disks and seeds after 5 days of inoculation. When the inoculated barley seeds were immersed in sterilized distilled water for 5 minutes, abundant conidia of B. dothidea were exuded from mature pycnidia. Conidia were held together by mucilage as they were released from an ostiole. Compared with the conventional method for inoculum preparation using agar media, such as potato-dextrose agar and oatmeal agar, this method could minimize the tedious work required for inoculum preparation within a shorter period of time.

• 한국유기농업학회지
• /
• 제6권1호
• /
• pp.151-160
• /
• 1997

Azospirillum sp., photosynthetic bacteria(Rhodopseudomonas sp.) and Pseudomonas sp. were separated and screened from soil and soilless culture, and identificated. The antifungal activities against root-infected pathogens and plant growth promoting effects of the cultured solution of the starins(5.0$\times$105 cells/$m\ell$) in the peatmoss compost on the early growth of cucumber and tomato seedling were investigated. Azospirillum sp. and Pseudomonas sp. showed a antifungal activities against Fusarium sp., Pythium sp. and Rhizoctonia sp in thed ranges of 51.0% to 72.0% on potato dextrose agar medium, however photosynthetic bacteria had not antifungal activities. When cultured solution of Azospirillum sp., photosynthetic bacterial and Pseudomonas sp. were bacterialized by mixing with peatmoss compost, early growth of cucumber and tomato in terms of plant height, number of leaves, leaf area, root length, fresh anf dry weight of leaf, stem and root were promoted, especially photosynthetic bacteria had a the best plant growth promting activities.