• Horticultural Science & Technology
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• v.34 no.5
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• pp.677-691
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• 2016

To assess South Korean commercial tomato cultivars, regular and cherry tomato cultivars were grown in the greenhouse and evaluated for color attributes, titratable acidity, pH, total soluble solids, carotenoids (lycopene and ${\beta}$-carotene), total phenols, flavonoids, vitamin C, and antioxidant activity. Significant differences (p < 0.05 using Duncan's multiple range test (DMRT)) were observed in the levels of most phytochemicals, quality parameters, and antioxidant activity among the twenty South Korean tomato cultivars tested. Lycopene and ${\beta}$-carotene contents varied significantly (p < 0.05 using DMRT), from $0.95mg{\cdot}100g^{-1}$ to $5.12mg{\cdot}100g^{-1}$ and $0.65mg{\cdot}100g^{-1}$ to $3.56mg{\cdot}100g^{-1}$ of fresh weight, respectively. ${\beta}$-carotene contents exhibited the highest genetic variation (59.2%), followed by naringenin (52.8%) and other phytochemicals. Most of the cherry tomato cultivars had statistically higher levels (p < 0.05 using DMRT) of carotenoids, phenols, flavonoids, vitamin C, and antioxidant activity compared to the regular tomato varieties, suggesting their higher nutritional value. Lycopene content was highest in the cultivars YoYo, Jicored, Titi-Chal, TY-Endorphin, and Rubyking. Cultivars Rubyking, TY-Endorphin, and Titi-Chal also showed relatively higher antioxidant activities in three assays: 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and ferric ion reducing antioxidant power (FRAP) assays. All the antioxidants, except luteolin, were positively correlated with antioxidant activities; the highest correlation was observed between total phenol and antioxidant activities, followed by the correlation between rutin and vitamin C. Cultivars identified to have superior nutritional status would be useful in tomato breeding programs to further improve quality and health benefits of tomatoes for the fresh and processed markets.

• Research in Plant Disease
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• v.24 no.4
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• pp.292-301
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• 2018

Alternaria leaf spot disease has been a concern during a tomato production in greenhouse. In vitro antifungal activities of vapours of four plant essential oils, cinnamon oil, fennel oil, origanum oil and thyme oil, were investigated during in vitro conidial germination and mycelial growth of Alternaria alternata causing the tomato leaf spots to find eco-friendly alternatives for chemical fungicides. The four plant essential oils showed different antifungal activities against in vitro conidial germination of A. alternata in dose-dependent manners, and cinnamon oil vapour was most effective to suppress the conidial germination. The four plant essential oils showed similar antifungal activities against the in vitro mycelial growth of A. alternata in dose-dependent manners, but low doses of thyme oil vapour slightly increased in vitro mycelial growth of A. alternata. Necrotic lesions on the A. alternata-inoculated tomato leaves were reduced differently depending on kinds and concentrations of plant essential oils. Delayed conidial germination and germ-tube elongation of A. alternata were found on the tomato leaves treated with cinnamon oil and origanum oil vapours at 6 hpi. These results suggest that volatiles from cinnamon oil and origanum oil can be provided as alternatives to manage Alternaria leaf spot during the tomato production eco-friendly.

• Horticultural Science & Technology
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• v.35 no.1
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• pp.79-87
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• 2017

We examined the effect of two greenhouse covering materials (glass or solid polycarbonate sheets) on the light environment and growth of tomato and cucumber plants. Spectral analysis showed that polycarbonate sheets entirely blocked radiation in both the UV - B (300 - 320 nm) and UV - A (320 - 400 nm) ranges, whereas glass transmitted UV - A and was only opaque to UV - B. The transmittance of photosynthetically active radiation (400 - 700 nm) and near infrared radiation (700 - 1100 nm) was higher in polycarbonate than glass. Air and soil temperatures were not significantly different between greenhouses covered with either material. The growth of cucumber plants was slightly affected by covering materials, whereas no significant changes in growth parameters were observed for tomato plants. The color parameters of tomato fruits were affected by the cover material, whereas cucumber fruits showed similar coloration in both glass and polycarbonate greenhouses.

• The Plant Pathology Journal
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• v.21 no.4
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• pp.391-394
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• 2005

Tomato seedlings (20- days old) were transplanted to infested soil with Orobanche cernua and non-infested soils. All plants were maintained under 0, 25, 50 and 75 mM NaCl soil salinity levels throughout their growing period under greenhouse conditions. Plants grown in O. cernua infested soil infIltrated with 0, 25, and 50 mM NaCl solution for salinity showed significant reduction in their growth as well as their total soluble carbohydrate and protein contents in compared with those grown in non-infested soil. However, under 75 mM NaCI salinity level all plants showed similar growth values whether they were grown in O. cernua infested or non-infested soil. Starting at the fifth and through out the eighth week after transplantation there was a significant increase in plant height in the 0, 25 and 50 mM NaCl irrigated plants over other treatments. Irrigation with 50 mM NaCl significantly reduced the emergence of O. cernua (2/plant) and the number of attachments (4.4 attachments) on roots of tomato. Furthermore, irrigation with 75 mM NaCl resulted in complete elimination of O. cernua emergence.

• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.251-254
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• 2011

Botrytis cinerea infects stems and leaves of greenhouse tomatoes and can cause serious economic losses. This study was conducted to develop environment-friendly control method against tomato gray mold. Antagonistic microorganisms (bacteria) were screened for control activity against Botrytis cinerea, both in vitro and in vivo, using stem sections. One hundred bacterial strains were isolated from the rhizospheric soil of various plants including tomato. These strains were screened for growth inhibition of Botrytis cinerea on agar plate by the dual culture and thirty strains showing strongly inhibitory effect against the pathogen were selected first. Among thirty strains, JB 5-12, JB 22-2, JB 22-3, U 4-8 and U46-6 reduced significantly disease incidence, when applied simultaneously with the pathogen. These results suggested that five antagonistic bacteria strains selected have the potential to control tomato gray mold in organic farming.

• Korean journal of applied entomology
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• v.55 no.2
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• pp.109-117
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• 2016

We investigated the control of Bemisia tabaci adults in tomato greenhouses using the eggplant as a trap plant with 4 systemic chemicals. The control effect of dinotefuran SG 50% on tobacco whitefly adults was 80% mortality, the highest than that cyantraniliprole, pyridaben and clothianidin, 51.0%, 12.4% and 11.0% respectively when all chemicals with recommended doses were used. Dinotefuran was applied at various doses and was observed to be most effective above 200ppm (88.4%)t. The control effect of dinotefuran lasted for appromimately nine 9 days and the density of tobacco whitefly adults increased there after. In field tests, the densities of tobacco whitefly adults on tomato shoots were highest at points 0, 15 and 20 m from the eggplant traps and lowest at 5 and 10 m. When the density of tobacco whitefly was low and the eggplants with dinotefuran SG 50% were placed in the tomato greenhouse at 10 m intervals, the overall density of tobacco whitefly adults was lower. In addition, densities were higher at the side of the greenhouse than in the interior and further away from the eggplant. When the density of tobacco whitefly was high and the eggplants with dinotefuran were placed at 5 m intervals, the density of tobacco whitefly at each 5 m point decreased. Theses results confirm that the eggplant is an effective trap plant for attracting tobacco whitefly audlts and combined with dinotefuran SG 50% decreases the density of tobacco whitefly in tomato greenhouses.

• Korean Journal of Agricultural and Forest Meteorology
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• v.20 no.2
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• pp.183-189
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• 2018

This study was carried out to investigate the effect of plant growth and production of tomato (Lycopersicon Esculentum Mill cv. Tefunis) according to the water content of non-recycled rockwool culture in high-rise tomato greenhouse. Daily irrigation amount was 3.8 times higher in the irrigation control by Integrated Solar Radiation (ISR) than in the Frequency Domain Reflectometry (FDR) sensor. Water content of ISR and FDR was 90-95 and 60-65%, respectively. Plant height and weight of tomato fruit was 1.2-1.9 times longer and 1.2-2.0 times heavier in the ISR than in the FDR sensor, respectively. No significantly differed to sugar content of tomato by treatments. Marketable fruits were the higher 1.3 times in the ISR compared with the FDR sensor. Cracking percentage in the ISR was also the higher 2.0 times compared with FDR sensor. Therefore, Irrigation control by ISR was appropriate to improve of plant growth and production of tomato with non-recycled rockwool culture in greenhouse during long-term cultivation.

• Korean journal of applied entomology
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• v.52 no.1
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• pp.23-27
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• 2013

Investigations were conducted to prevent entrance of Bemisia tabaci (Gennadius) with very fine mesh nets. B. tabaci vectors tomato yellow leaf curl virus in tomatoes. B. tabaci could be completely prevented to penetrate into an 83 mesh net, though few of them passed the 60 mesh net. An independent 60 mesh net cage was built within one of the three interconnected common plastic greenhouse ($21.0{\times}18.3m$) in order to find its usefulness as a crop protection tool from insect pests. TYLCV infected tomato plants were not detected, though a few eggs of B. tabaci and mines of Liriomyza trifolii (Burgess) were detected locally at the entrance of the sliding door. There were practically no significant differences between treatments of nets and the conventional plant height, leaf length and width, number of floret clusters, sugar brix, and product yield. In viewpoints of commercialization, it could be considered highly prospectful to apply to the nets to glasshouses or other greenhouses in which the growing period of crops is long, if the nets were used in the openings of sides, ceilings, and entrances of the greenhouse. However, it might be necessary to take preventive measures for occurrences of insect pests living in soil, temporarily or permanently, as well as high humidity diseases.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.3
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• pp.202-206
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• 2015

'Hei' (Lycopersicon Esculentum Mill.) Black Tomato examined changes in fruit shape, fruit weight and cracking percentage with increasing temperature in high-rise tomato greenhouse during long-term cultivation in summer season. Fruit diameter is greater than fruit length from the first cluster to the ninth cluster. However, fruit length is longer than fruit diameter from the tenth cluster to the fifteenth cluster. Fruit shape index (L/D) is below 100% from the first cluster to the ninth cluster and above 100% from the tenth cluster to the fifteenth cluster. Fruit weight was decreased during temperature increasing in greenhouse. However, fruit cracking percentage was increased to temperature increasing during cultivation period. Thus, fruit shape, fruit weight and fruit cracking of 'Hei' black tomato were influenced by increasing of temperature in greenhouse during long-term cultivation.

• Journal of Bio-Environment Control
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• v.3 no.1
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• pp.36-41
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• 1994

The major objective of this study is to develop a method of zone cooling during summer day using heat pump for year- round cultivation. The efficiency of cold water cooling and fog cooling was investigated. In order to prevent the occurrence of blossom - end rot in tomato, cooling was induced together with air flow of the fruit treatment as well as promoting air circulation in the plant treatment was induced. The following results were obtained : 1) The temperature in the cold water cooling district was 1$0^{\circ}C$ lower than greenhouse temperature and the temperature in the fo8 cooling district was about 5$^{\circ}C$ lower than the greenhouse. 2) Regardless of cooling method, the treatment of air flow on fruit did not affect the fruit but prevent blossom-end rot. There was 34.5% occurrence rate of blossom -end rot in non-air flow district of cold water cooling 54.5% in non-air flow district of fog cooling and 78% in fog circulation cooling district. The cooling efficiency using cold water cooling method induced enough cooling at critical temperature for growth and development and the occurrence of blossom -end rot was lower than fog cooling. Fog cooling in culture district with air circulation did not induce and difference in temperature but caused an Increase in humidity resulting in 24% increase in the occurrence of blossom-end rot. Thus the occurrence of blossom-end rot in tomato caused by environmental factors can be attributed more to humidity than to temperature.