• Korean Journal of Environmental Agriculture
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• v.33 no.1
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• pp.17-23
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• 2014

BACKGROUND: Crop rotation is often used as a solution to eradicate nematodes in soils used in plastic film houses for long-term cultivation of oriental melon. However, it is not clear if the double-cropping is effective in reducing nematode populations in soils. METHODS AND RESULTS: Nematode population in plastic film house soil was measured during oriental melon cultivation from April to July in short term crop rotation systems of oriental melon. Double-cropping of chinese cabbage in open-field for 3-4 months following oriental melon in plastic film houses could not prevent the build-up of high population density of nematodes. However, double-cropping of dropwort in flooded soil for 3-4 months following oriental melon in plastic film houses could effectively reduce the nematode population during the successive year of oriental melon cultivation. The reduced nematode population in soils of oriental melon-dropwort double-cropping system was continued until the mid season of progressive year oriental melon cultivation. Application of nematicide to soil before growing oriental melon in the oriental melon-dropwort double-cropping was very effective in preventing the build-up of high population density of nematode in plastic film house soils. CONCLUSION: Short-term introduction of crop rotation was not effective in suppression of high population density of nematodes in plastic film house soils of long-term year-to-year production of oriental melon. For securing the soil productivity and sustainability of plastic film house, various physical, chemical, and agronomic practices should be properly combined together.

• Korean Journal of Environmental Agriculture
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• v.34 no.4
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• pp.253-259
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• 2015

BACKGROUND: During the off-season, the cultivation of Chinese cabbage and water dropwort is often used to desalinize plastic film house soils. The objective of this study was to verify the effect of double-cropping systems on the salt removal in oriental melon cultivated plastic film house soils.METHODS AND RESULTS: Electrical conductivity (EC) and soluble salt contents were measured in soils collected from plastic film houses of oriental melon cultivation before and after the off-season crop cultivation. Also the same measurements were performed in the next oriental melon season to estimate the desalinization effect of double-cropping systems. During the cultivation of Chinese cabbage under open-field condition, EC_eof surface soil was reduced from 6.0 to 0.8 dS/m. Double-cropping of water dropwort in flooded soil was also efficient in removing the salts accumulated during oriental melon cultivation. In the house soils where salts were removed during the off-season crop cultivation, soil EC_ewas maintained below 3 dS/m during the next oriental melon cultivation season.CONCLUSION: The off-season cropping under open-field or flooded condition was effective in desalinization of plastic film house soils. Since the salt removal effect is not expected to last for several years, the double-cropping system should be introduced every season to maintain soil EC below the critical level.

• Journal of Biosystems Engineering
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• v.33 no.3
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• pp.186-195
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• 2008

In this paper, a prototype tele-operative system with a mobile base was developed in order to automate cultivation of house melon. A man-machine interactive hybrid decision-making system via tele-operative task interface was proposed to overcome limitations of computer image recognition. Identifying house melon including position data from the field image was critical to automate cultivation. And it was not simple especially when melon is covered partly by leaves and stems. The developed system was composed of 5 major modules: (a) main remote monitoring and task control module, (b) wireless remote image acquisition and data transmission module, (c) three-wheel mobile base mounted with a 4 dof articulated type robot manipulator (d) exchangeable modular type end tools, and (e) melon storage module. The system was operated through the graphic user interface using touch screen monitor and wireless data communication among operator, computer, and machine. Once task was selected from the task control and monitoring module, the analog signal of the color image of the field was captured and transmitted to the host computer using R.F. module by wireless. A sequence of algorithms to identify location and size of a melon was performed based on the local image processing. Laboratory experiment showed the developed prototype system showed the practical feasibility of automating various cultivating tasks of house melon.

• Journal of Korean Society of Rural Planning
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• v.20 no.4
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• pp.45-54
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• 2014

The main purpose of this study is to provide the back-from-city farmers with the information about the melon cultivation technology by surveying 268 farm houses in the major melon producing districts such as Seongju and Chilgok. For the purpose, this study classifies the essential technologies that the melon experts think as most important into 6 categories: size of plastic film house, covering film, varieties of oriental melon, lagging cover, ventilation method and ways to reduce repeated-cultivation damage. The result of the study shows that the back-from-city farmers should consider the following items when they choose to cultivate oriental melons. For the size of plastic film house, the ventilation method and the covering film of plastic film house, it is better to choose the latest technology. Even though it may require larger initial investment, the latest technology can increase the production and lower the cost. In case of variety, it is better to choose popular or the most widely grown ones rather than the new ones. The lagging cover should be selected in consideration of climate conditions such as average temperature and humidity, transplant time and harvest time of the farming region.

• Korean Journal of Environmental Agriculture
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• v.28 no.3
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• pp.281-288
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• 2009

The strobilurin fungicides, azoxystrobin and kresoxim-methyl, were investigated to know the biological half-lives and dissipation patterns in Korean melon under plastic film house condition. Used pesticides for field application were 20% azoxystrobin of suspension concentrate and 47% kresoxim-methyl of water dispersible granule. Two pesticides were sprayed at recommended and double dose rate. Pesticide residues in Korean melon were analyzed until 14 days after application. The azoxystrobin was analyzed by HPLC equipped with UV detector after cleanup with florisil glass column. Initial residue concentrations of azoxystrobin in Korean melon at recommended and double dose rate were 0.09 mg/kg and 0.14 mg/kg, respectively. Those were less than 0.2 mg/kg maximum residue limit of Korean melon established by KFDA. The biological half-lives of azoxystrobin in Korean melon were 4.7 days at recommended dose rate and 7.8 days at double dose rate. Initial concentrations of kresoxim-methyl which was analyzed by GLC-ECD in Korean melon at recommended and double dose rate were 0.10 mg/kg and 0.23 mg/kg, respectively. Those were less than 1.0 mg/kg, MRL. The biological half-lives of kresoxim-methyl in Korean melon were 4.1 days at recommended dose rate and 4.8 days at double dose rate. The residue amounts of both pesticide was lower than MRL and biological half-lives were not so long. Because the weight of Korean melon under plastic film house condition was fast increased during cultivation.

• Korean Journal Plant Pathology
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• v.12 no.1
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• pp.116-120
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• 1996

Water-soaked spots or lesions were observed on fruits or stems of melon plants at house-melon farms in Andong, Korea. The symptoms developed to soft rot of the fruits of wilting of the whole plants. The causal organism isolated from the water-soaked le-sions was identified as Erwinia carotovora subsp. carotovora based on the morphological and physiological characteristics. The causal bacterium was susceptible to not only two kinds of medical antibiotics but also two kinds of agrochemicals tested. Since the bacterial soft rot is a first described bacterial disease in melon in Korea, we propose to name the disease as "bacterial soft rot of melon".

• Korean Journal of Soil Science and Fertilizer
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• v.36 no.6
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• pp.407-416
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• 2003

Although the requirement and optimum soil level of Si for oriental melon are still not well understood, silicate fertilizer is commonly applied to the oriental melon in plastic film houses where soil silicate level is relatively high. In this research the effects of silicate fertilizer on growth, fruit yield and fruit quality of oriental melon, and soil properties were investigated in plastic film house where the soil available silicate was $212mg\;SiO_2\;kg^{-1}$. Silicate fertilizer was applied in the rates of 100, 200, and $300kg\;10a^{-1}$. The application of silicate fertilizer could not increase the early growth of oriental melon, and also the fruit yield and quality were not different among the treatments. Available Si and P contents in soils and also Si and P contents in leaf of oriental melon of the different treatments were not significantly different. In the relationship between total Si in oriental melon leaf and soil silicate extracted by 1 N sodium acetate, optimum soil available silicate level for oriental melon was found to be around $100mg\;SiO_2\;kg^{-1}$. These results indicate that the additional silicate fertilization in soils of available silicate higher than $100mg\;SiO_2\;kg^{-1}$ is unnecessary, and such application of silicate can not have any beneficial effect on the growth and fruit yield of oriental melon.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.6
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• pp.334-339
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• 2005

Although phosphogypsum can have profound effects on both the physical and chemical properties of certain soils with supplying the essential elements, no widespread use of by-product phosphogypsum will be made unless such uses pose no threat to the public health and soil contaminations. This study was conducted to evaluate the effects of phosphogypsum on the growth of oriental melon and soil properties in plastic film house. Phosphogypsum was treated at the rate of $70kg\;CaO\;10a^{-1}$ and the effects were compared with the treatment of Ca-Mg carbonate. In the treatment of phosphogypsum, early growth of oriental melon was significantly increased comparing to the growth in the Ca-Mg carbonate treatment. Total fruit yield was not different between the treatments of phosphogypsum and Ca-Mg carbonate, but marketable fruit yield was higher in the phosphogypsum treatment. Although Ca and S contents in oriental melon were increased in the phosphogypsum treatment, contents of toxic heavy metals including As, Cd, Cr, Cu, and Pb were not different between the two treatments. Also, soil pH and contents of extractable toxic metals in the soil were not significantly different between the two treatments after the experiment. These results suggest that phosphogypsum can be a valuable substitute for lime materials in high pH soils of plastic film house.

• Mycobiology
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• v.37 no.2
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• pp.158-159
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• 2009

In 2007 to 2008, a fruit rot of Melon (Cucumis melo L.) caused by Sclerotium rolfsii occurred sporadically in a farmer's vinyl house in Jinju City. The symptoms started with watersoaking lesion and progressed into the rotting of the surface of fruit. White mycelial mats appeared on the lesion at the surface of the fruit and a number of sclerotia formed on the fruit near the soil line. The sclerotia were globoid in shape, 1${\sim}$3 mm in size, and white to brown in color. The hyphal width was measured 3 to 8 ${\mn}$. The optimum temperature for mycelial growth and sclerotia formation was 30 on PDA. Typical clamp connections were observed in hyphae of grown for 4 days on PDA. On the basis of symptoms, mycological characteristics and pathogenicity to the host plant, this fungus was identified as Sclerotium rolfsii Saccardo. This is the first report of the fruit rot of Melon caused by S. rolfsii in Korea.

• Journal of Biosystems Engineering
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• v.33 no.3
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• pp.196-203
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• 2008

Hybrid robust image processing algorithm to extract visual features of melon during the cultivation was developed based on a wireless tele-operative interface. Features of a melon such as size and shape including position were crucial to successful task automation and future development of cultivation data base. An algorithm was developed based on the concept of hybrid decision-making which shares a task between the computer and the operator utilizing man-computer interactive interface. A hybrid decision-making system was composed of three modules such as wireless image transmission, task specification and identification, and man-computer interface modules. Computing burden and the instability of the image processing results caused by the variation of illumination and the complexity of the environment caused by the irregular stem and shapes of leaves and shades were overcome using the proposed algorithm. With utilizing operator's teaching via LCD touch screen of the display monitor, the complexity and instability of the melon identification process has been avoided. Hough transform was modified for the image obtained from the locally specified window to extract the geometric shape and position of the melon. It took less than 200 milliseconds processing time.