• Journal of Bio-Environment Control
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• v.23 no.3
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• pp.167-173
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• 2014

This research was conducted to establish appropriate methods to prune tomato side stems during summer. Cherry tomatoes "Unicorn" (Monsanto Korea, Korea) were grown in the coir based growing medium, and irrigation was controlled time based system. There were three pruning treatments: 1) removing all side stems (ACUT), 2) remaining two leaves on the side stems right below any cluster (PCUT), and 3) remaining two leaves on all side stems (LEFT). Experimental results showed that the occurrence of swollen stems, a symptom of nutrient excess, was influenced by side stem pruning due to blocking of consumption of photosynthetic products. The photosynthetic rate was not different between leaves on main stem and those on side shoots. Therefore the differences in the total amounts of photosynthetic products seemed to come out from the differences in leaf areas on each treatments, influencing on fruit yield difference. The yields and harvesting rates were better in ACUT treatment when tomato plants were harvested until $5^{th}$ cluster, however tomato yield was higher in LEFT treatment when more then $5^{th}$ clusters were harvested.

• Horticultural Science & Technology
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• v.28 no.5
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• pp.783-789
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• 2010

The effective method for heating root-zone during winter season was studied in the aspects of growth, yield and economics for tomato ($Solanum$ $lycopersicum$) in perlite bag culture. There were four root-zone heating treatments: two hours heating from one hour before to one hour after sunrise, four hours from two hours before to two hours after sunrise, 15 hours after sunset, and no heating. The growth characteristics of the upper parts of plants were not significantly different among the treatments, but root volume increased with longer heating of the root zone. The Plant Development Index, using stem diameter and the length between growing tip and the upper flowering truss, showed relation between yield per cluster and growth pattern. The treatment heating for four hours was the most economic in terms of growth and yield of tomato.

• Journal of Bio-Environment Control
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• v.24 no.4
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• pp.301-307
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• 2015

High quality transplants are critical for success in crop production. Increasing numbers of growers purchase their transplants from specialized transplant producers instead of growing their own transplants. A drawback of purchasing transplants is the risk of deterioration to transplants during transportation from transplant producers to the growers. This study evaluates the influence of temperature on the quality of grafted tomatoes transplants (Solanum lycopersicum cv. Super Doterang), in order to propose optimum temperature condition for the transportation of grafted tomato transplants. Grafted tomato transplants with visible flower trusses were exposed to different air temperature ($10^{\circ}C$, $25^{\circ}C$, or $40^{\circ}C$) for 2, 4, or 6 hours. After treatment, the NDVI (Normalized Difference Vegetation Index) values of tomato transplants treated at 25 and $40^{\circ}C$ were lower than that at $10^{\circ}C$. The root fresh weight was lowest at $40^{\circ}C$. After transplanting, the transplants that were exposed to the air temperature of $40^{\circ}C$ exhibited chlorosis and blight on lower leaves. The degree of damage on leaves was severer as the high temperature exposure time was longer. The temperature conditions during the transportation also influenced the growth, flowering and fruit set of tomatoes after transplanting. The fruit number and weight of first truss was lowest at $40^{\circ}C$ for 6 hours. Accordingly, it is recommended that the temperature during the transportation should be controlled and kept at the range from 10 to $25^{\circ}C$ even though the period is short (within as six hours) in order to maintain the quality of transplants.

• Journal of Bio-Environment Control
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• v.10 no.1
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• pp.30-35
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• 2001

This experiment was undertaken to investigate the effect of root zone temperature during the night on absorption of mineral nutrients, growth, and fruit yield of the truss-limited hydroponic tomatoes in winter. The root zone temperature was either controlled to 10, 15, 20, $25^{\circ}C$, or left uncontrolled at ambient temperatures. Temperature of the covered beds rose as root zone temperature was raised, but it in all treatments was less than 3$^{\circ}C$ higher than that in the control. Raising root zone temperature, except $25^{\circ}C$, showed positive effect on plant height, leaf length, stem diameter, and plant fresh and dry weight, but not on T/R ratio which was the greatest in the control. Root activity in all treatments except $25^{\circ}C$ increased as compared to the control. Mean fruit weight, fruit count per plant, and fruit yield were the greatest in 2$0^{\circ}C$ treatment. Root zone temperature did not significantly affect the contents of total nitrate and magnesium in leaves, stems and roots. Concentrations of phosphate and calcium increased in leaves and stems, but decreased in roots as root zone temperature increased. Overall, 2$0^{\circ}C$ treatment gave the greatest growth and energy efficiency.