• Journal of Bio-Environment Control
• /
• v.23 no.1
• /
• pp.11-18
• /
• 2014

To investigate the influence of surrounding environment on the plant temperature and examine the effect of plant temperature control by fogging and airflow, plant temperature of tomato, inside and outside air temperature and relative humidity, solar radiation and wind speed were measured and analyzed under various experimental conditions in plastic greenhouse with two-fluid fogging systems and air circulation fans. According to the analysis of plant temperature and the change of inside and outside air temperature in each condition, inside air temperature and plant temperature were significantly higher than outside air temperature in the control and shading condition. However, in the fogging condition, inside air temperature was lower or slightly higher than outside air temperature. It showed that plant temperature could be kept with the temperature similar to or lower than inside air temperature in fogging and airflow condition. To derive the relationship between surrounding environmental factor and plant temperature, we did multiple regression analysis. The optimum regression equation for the temperature difference between plant and air included solar radiation, wind speed and vapor pressure deficit and RMS error was $0.8^{\circ}C$. To investigate whether the fogging and airflow contribute to reduce high temperature stress of plant, photosynthetic rate of tomato leaf was measured under the experimental conditions. Photosynthetic rate was the highest when using both fogging and airflow, and then fogging, airflow and lastly the control. So, we could assume that fogging and airflow can make better effect of plant temperature control to reduce high temperature stress of plant which can increase photosynthetic rate. It showed that the temperature difference between plant and air was highly affected by surrounding environment. Also, we could estimate plant temperature by measuring the surrounding environment, and use it for environment control to reduce the high temperature stress of plant. In addition, by using fogging and airflow, we can decrease temperature difference between plant and air, increase photosynthetic rate, and make proper environment for plants. We could conclude that both fogging and airflow are effective to reduce the high temperature stress of plant.

• Korean journal of applied entomology
• /
• v.59 no.4
• /
• pp.411-416
• /
• 2020

Whitefly populations found in heated tomato greenhouses were monitored across three locations in Korea (Nonsan and Buyeo, Chungnam Province; Iksan, Jeonbuk Province) from November to May during the 2015 -2018 growing seasons. From May to October, surveys were conducted in Jangsu (Jeonbuk Province), where retarding cultivation was performed. Whitefly populations were classified and quantified by location and year. The dominant species were Trialeurodes vaporariorum (Westwood) and Bemisia tabaci (Gennadius). The species populations were mixed, but the frequency of occurrece of B. tabaci was higher than that of T. vaporariorum. Although whitefly populations started to increase in late March, they sharply increased in May and the highest population density was observed at the end of the harvest season. Therefore, the management of greenhouse tomato whiteflies through monitoring should begin in early March. In the case of retarding cultivation, the management of whitefly populations should be implemented in June, before the density of whitefly populations increases.

• Journal of Practical Agriculture & Fisheries Research
• /
• v.18 no.1
• /
• pp.71-78
• /
• 2016

The present study was performed to examine the high temperature adaptability with CO₂ treatment for tomato under the condition of greenhouse cultivation during summer season. The plants with the CO₂ concentration of 1000 ppm recorded higher scores in Fm/Fo and Fv/Fm but lower score in Fo than others through the measurement of chlorophyll fluorescence, which implicated that the plants with the CO₂ concentration of 1000 ppm had more adaptability to high temperature than the others. At the condition of the same air temperature as 30℃ and 40℃, the photosynthetic rate was increased with the increase of CO₂ concentration. When in the high air temperature state of 40℃, although the photosynthic rate was low in comparison with 30℃, its value was about 18.5umolm^-2s^-1 in case of 1000ppm. The higher concentration of CO₂ made the more activated anti-oxidation enzyme (superoxide dismutase and peroxidase) for the both cultivars as 'momotaro' and 'minichal'. The cultivar of 'minichal' performed the high temperature limit as 41℃ at the CO₂ condition of 500 ppm and 43℃ at the CO₂ condition of 1000 ppm through the estimation on the variation of chlorophyll fluorescence Fo by CO₂ concentrations.

• Journal of Environmental Science International
• /
• v.32 no.12
• /
• pp.973-978
• /
• 2023

This study determined the mechanisms of selection of companion plants that will increase natural enemies and compared and analyzed the effect of suppression of pest density and changes in pest and natural enemy density and spatial distribution, aiming to select suitable companion plants to control major pests that are problematic in organic tomato facility cultivation. As a result of the companion plant selection, 13.5 days were identified in the area with daily flowers among five species of flowering plants. In the experiment to determine the timing of natural enemies, the best results were found in the treatment group introduced two weeks before the pest occurred. As a result of the actual package test, farmers could see that the density of greenhouse pollen decreased significantly (100-500% for adults and 11-67% for larvae compared to no treatment) in the treatment with companion plants. Based on the results of this study, we expect that ecological pest management using companion plants that attract natural enemies will help to increase biodiversity through vegetation management, secure the safe production of organic products and improve the sustainability of agriculture.

• Korean Journal of Plant Resources
• /
• v.28 no.2
• /
• pp.263-270
• /
• 2015

To reduce the injury by continuous cropping system of tomato cultivation, green manure crops (GMCs) such as hairy vetch and rye were applied, Nutrient contributions of N, P₂O₅, K₂O, CaO, and MgO in hairy vetch were 26.2, 5.8, 10.2, 6.6, and 1.5 ㎏/10a, respectively. Nutrient contributions of N, P₂O₅, K₂O, CaO, and MgO in rye were 9.1, 4.2, 11.8, 3.8, and 3.1 ㎏/10a, respectively. After incorporation of GMCs into soil, bulk density in soil with GMCs was lower than that in soil without GMCs (control). In soil after incorporation of GMCs, pH was not different in all treatment conditions, and ranged from 6.37~6.52. EC in soil after incorporation of GMCs was lower than that in soil without GMCs. The OM, T-N, and avail. P₂O₅ contents in soil with GMCs were higher than those in soil without GMCs. The tomato growths were increased in the rotational cropping system (RCS) as compared to continuous cropping system (control and without NPK). Also the density of Pseudomonas corrugata in soil with GMCs was lower than that in soil without GMCs (control). This study suggest that the RCS using GMCs showed lower disease outbreak density in soil for tomato cultivation as compared to RCS without GMCs. Especially, the GMCs was good effect for reduction of continuous cropping injury of tomato.

• Korean Journal of Soil Science and Fertilizer
• /
• v.43 no.4
• /
• pp.466-470
• /
• 2010

Food contamination through antibiotic uptake by plants has been one of the major concerns regarding animal manure amendment to agricultural land. Antibiotic uptake by plants was tested with three veterinary antibiotics such as chlortetracycline (CTC), tylosin (TYL), and sulfamethazine (SMT) and three plants such as lettuce, tomato, and hairy vetch. Antibiotic-treated swine slurry was applied to a greenhouse soil before transplanting or sowing the plants. The treated antibiotic concentrations to the swine slurry were 22.9 mg CTC $L^{-1}$, 27.8 mg TYL $L^{-1}$, and 32.4 mg SMT $L^{-1}$. Lettuce was harvested on 64 days after transplanting and 94 days for tomato and hairy vetch. Concentrations of CTC were 3.4 ng $g^{-1}$ for lettuce and 0.7 ng $g^{-1}$ for tomato on a fresh weight basis. For TYL, 20.1 ng $g^{-1}$ from lettuce leaves and 3.0 ng $g^{-1}$ from whole hairy vetch were detected. Sulfamethazine showed greatest concentration among the three antibiotics, 63.3 ng $g^{-1}$ in lettuce leaves, 30.2 ng $g^{-1}$ in tomato fruits, and 20.9 ng $g^{-1}$ in hairy vetch. The results imply that antibiotic uptake by plants may be dependent on antibiotic type and plant type.

• Korean journal of applied entomology
• /
• v.53 no.4
• /
• pp.435-440
• /
• 2014

The number of Bemisia tabaci adults attracted to horseweed, thistle, red bean, cucumber, and tomato plants, as measured by the number stuck to yellow sticky traps, was investigated in a polyvinyl greenhouse for growing tomatoes using organic methods. The number was highest on cucumber plants in the early days of B. tabaci infestation, but was highest on horseweed overall. Of the eight species of beans tested, B. tabaci adults were most attracted to Ultari-Gangnang; however, beans were not effective trap plants for B. tabaci. Measurement of olfactory behavioral response using a four-choice olfactometer showed that B. tabaci adults preferred horseweed to cucumber, eggplant, or tomato. The developmental period of B. tabaci eggs and larvae was shorter at high temperature. At $30^{\circ}C$, the developmental period of eggs and larvae on horseweed were reduced approximately 0.5 and 1 day, respectively, compared to those on cucumber or tomato.

• Research in Plant Disease
• /
• v.10 no.1
• /
• pp.58-62
• /
• 2004

Contamination level and characteristics of Ralstonia solanacearum in soil of greenhouses cultivating tomato plants in Chungbuk province was determined. R. solanacearum was isolated with the semiselective media in 27 greenhouse soil samples out of 133 greenhouses soil investigated, which indicates 20.3 ％ of tomato cultivating greenhouses in Chungbuk contaminated with the bacterial wilt pathogen. Density of R. solanacearum was estimated to 10$^{2.4}$ cfu/g in the contaminated soil. All 71 isolates of R. solanacearum which containing 12 isolates from the diseased tomato plants were race 1, ann 35 isolates of them were biovar 3 and 36 isolates were biovar 4. More than 88％ of 71 isolates were inhibited growth on nutrient agar containing oxolinic acid 0.5 $\mu\textrm{g}$/ml, streptomycin 25 $\mu\textrm{g}$/ml, tetracycline 5 $\mu\textrm{g}$/ml and cupric sulfate 375 $\mu\textrm{g}$/ml (1.5 mM). The 11.3％, 4.2％ and 5.6 ％ of the isolates can grow on nutrient agar containing 10 times more oxolinic acid, streptomycin, tetracycline than minimal inhibitory concentration of the sensitive strains. Five isolates were resistant to 2 bactericides and one isolates was resistant to all 3 bactericides.

• Research in Plant Disease
• /
• v.15 no.1
• /
• pp.23-29
• /
• 2009

Cooking oil and yolk mixture (COY), a environmentally acceptable plant protection agent, and COY+$CaCO_3$+neem oil mixture were studied to control the powdery mildew occurring on eggplant, paprika, cherry tomato and maturity tomato in glass houses and vinyl houses during 2005 to 2007. The morphological changes of the pathogenic fungi on the leaf surface before and after treatment of COY were observed. COY made of rape seed oil and COY+$CaCO_3$+neem oil mixture were sprayed three times with 5 days interval to foliar parts of eggplant, paprika and tomato and the disease development were examined 5 days after final spray. In eggplant, the control efficacy of COY to powdery mildew was 94.6%. In paprika, the control efficacy of COY to powdery mildew was 91.6% and that of COY+$CaCO_3$+neem oil mixture was 96.2% that revealed little higher than COY itself. In tomatoes(cherry or maturity tomato), the control efficacy of COY were about 91 %, however, when COY mixture were sprayed to tomato leaves and stems the powdery mildew was controlled completely. Typical and healthy mycelia, conidiophores and condia were observed through scanning electron microscope in COY unsprayed leaf surface, on the other hand destroyed and winkled mycelia and conidiophores were observed in COY treated leaves regardless host plants nor taxonomic differences of fungi.

• Horticultural Science & Technology
• /
• v.34 no.3
• /
• pp.414-423
• /
• 2016

Growers in plug seedling production think that root media in which rockwool is a component has given rise to several environmental problems. Therefore, the demand for new materials as a substitute for rockwool has been increased. This study examined the possibility of cultivation of tomato plug seedlings using a newly developed growing medium with phenolic foam. Plug seeds of tomato cultivar 'Madison' were sown in four pellet-type growing media: Grodan rockwool (GRW), UR rockwool (URW), phenolic foam LC (LC) or phenolic foam LC-lite (LC-lite). Then, the seedlings were transplanted to the four cube-type growing media 19 days after sowing. Seeds were germinated in a growth chamber ($25{\pm}2^{\circ}C$, 80% relative humidity, and dark) for 4 days and then the seedlings were grown with a nutrient solution supplied by an overhead irrigation system in a greenhouse. Plant height, number of leaves, leaf area, and fresh or dry weight of tomato seedlings were the greatest for the seedlings transplanted to URW cube media after being grown on LC-lite pellets. Root grade was the greatest for the seedlings transplanted on LC or LC-lite cube media after being grown on LC pellets. Chemical properties of all media tested for tomato growth were maintained within a stable range, while physical properties of URW showed high values in container capacity, air space, and total porosity. These results demonstrated that the phenolic foam media were effective for seedling growth and can substitute for rockwool as a root medium.