• Journal of Bio-Environment Control
• /
• v.15 no.2
• /
• pp.173-176
• /
• 2006

The relationship between source leaf position and photo-assimilate translocation and distribution was characterized for tomato (Lycopersicon esculentum Mill) grown in the greenhouse. Three different positions of source leaf on the stem (first node above or below the first fruit cluster and $5^{th}$ node above the first fruit cluster) were tested for their influence on $^{14}CO_2$ assimilation and transfer to different parts of the plant. The leaves at the $5^{th}$ node above the first fruit cluster transferred the highest (57%) proportion of $C^{14}$ to other plant parts, followed by leaves home on the first node below the first fruit cluster (50%), and the first node above the first fruit cluster (39%). In all treatments, fruits served as the strongest sink for $C^{14}$, followed by stem, leaf, and root tissues. The leaf home on the $5^{th}$ node above the first fruit cluster transferred the largest amount of $C^{14}$ to the second fruit cluster.

• Journal of Bio-Environment Control
• /
• v.22 no.1
• /
• pp.35-41
• /
• 2013

This study was conducted to provide data necessary for reducing the condensation on greenhouse covering in winter season. The variation of VPD (Vapor Pressure Deficit) and condensation flux was analyzed in experimental tomato greenhouse. VPD values in experimental plastic greenhouse were greater than 0.2 kPa of disease prevention threshold, and lower than 0.5 kPa of threshold for dehumidification. The surface temperature of inside covering was slightly higher than the average temperature of outside and above curtain, and changed according to outside temperature. The humidity above curtain was nearly 100% and good condition for condensation. The humidity below curtain was 75~90% and comparatively stable condition for growing. The condensation flux value in experimental greenhouse corresponded with result of Seginer and Kantz (1986).

• Journal of Bio-Environment Control
• /
• v.31 no.1
• /
• pp.52-59
• /
• 2022

Pest control treatment was carried out using an unmanned automatic pesticide spraying system that can spray pesticides on crops while moving autonomously to control pests in vegetable greenhouse. As a result of examining the control effect on tomato and strawberry on thrips (Frankliniella occidentalis) and greenhouse whitefly (Trialeurodes vaporariorum) pests, 85.6% of yellow flower thrips were found in tomatoes and 87.5% in strawberries, and 81.7% (tomato) and 80.6% (strawberry) of greenhouse whitefly. In addition, the control effect according to the pesticide treatment method showed a control effect of 81.7% of the chemical spraying treatment by manpower and 83.9% of the automatic moving pesticide spraying treatment (F=22.1, p < 0.001). When comparing the control effect between the two treatment sections, there was no significance, but the automatic transfer spraying treatment showed a 2.2% higher effect. On the other hand, as a result of comparing the spraying time of the drug, the automatic unmanned control sprayer had a spraying time of 5 min/10a, which took about 25 min less than the conventional manpower spraying time of 25-30 min/10a. Based on these results, it was judged that the automatic transfer spraying method could be usefully used for efficient pest control in the facility greenhouse during the peak period of development.

• Korean Journal of Soil Science and Fertilizer
• /
• v.27 no.2
• /
• pp.78-84
• /
• 1994

Yield response of tomato to nitrogen and potassium fertilizer and the balance of the two elements were determined in salt-accumulated greenhouse soil to improve the efficiency of fertilizer appiication. The response of tomato yield to nitrogen and potassium fertilizer application was not significant. The current parameters such as OM and $K/{\sqrt{Ca+Mg}}$ that were used to determine the level of nitrogen and potassium fertilizer in open field were not suitable in salt-accumulated greenhouse soil condition. The temporal and spatial distribution of $NO_3{^-}-N$showed the same pattern to those of $Cl^-$ ion that is non-reactive with soil, while the content of Ex. K was extraordinarily high in soil after harvesting of tomato, which had experienced relatively dry condition during harvesting time. The loss of $NO_3{^-}-N$ and Ex. K out of 28cm below the soil surface was 2~5 and 1.5~3.5 times greater than the amount of nitrogen and potassium uptake by the plant.

• Korean Journal of Environmental Agriculture
• /
• v.21 no.4
• /
• pp.231-236
• /
• 2002

We studied the residual patterns of two fungicides, dichlofluanid and iprodione, in cherry tomato greenhouse after applying with the recommended and double dose. Also, the degradation patterns during storage periods of up to ten days were compared between at room temperature (20$^{\circ}C$) and at cold temperature (4$^{\circ}C$). Removal rates of fungicides by washing with tap-water and detergent solution (0.1%, 0.2%) were measured. Half-lives of dichlofluanid and iprodione in greenhouse cherrytomato were 2.2$\sim$3.5 and 3.3$\sim$5.4 days, respectively. During the storage period, the residues were dissipated more slow. Removal rates were 62.8$\sim$80.3% by tap-water, 60.4$\sim$83.1% by 0.1% detergent solution, and 65.3$\sim$77.6% by 0.2% detergent solution. So, we can predict of terminal residues from cultivation period to marketing, storage and consuming.

• Korean Journal of Organic Agriculture
• /
• v.20 no.1
• /
• pp.49-58
• /
• 2012

Greenhouse whitefly, $Trialeurodes$ $Vaporariorum$, is the most important insect pest in environmental friendly tomato production. Natural enemies, $Nesidiocoris$ $tenuis$ and environmental friendly agricultural materials (EFAM) are major control agents in Korea. The aim of the present work is to evaluate release time of $N.$ $tenuis$ in controlling of $T.$ $vaporariorum$ and to select environmental friendly agricultural materials (EFAM) to suppress both $T.$ $vaporariorum$ and $N.$ $tenuis$ which if the density were high causing necrotic rings. Six EFAM selected to control of $Trialeurodes$ $Vaporariorum$ in three times spray with seven days intervals. Three EFAM showed high mortality 67.7-70.5% in spray after release plot but low in release after spray plot. It should be careful to spray with $N.$ $tenuis$. When $N.$ $tenuis$ were early release at 7 days after transplanting which before occurring and establishment of greenhouse whitefly, it could suppress the density. Extracts of bead tree + matrin, matrin 1, Chrysanthemum showed high mortality on $T.$ $vaporariorum$ adults and $N.$ $tenuis$. The results suggested that this three EFAM could be control agents of the damage of necrotic rings from $N.$ $tenuis$.

• Journal of Bio-Environment Control
• /
• v.27 no.3
• /
• pp.239-244
• /
• 2018

The effect of the trap equipped with diverse light-emitting lamp on the lure efficiency of whitefly (Trialeurodes vaporariorum) was investigated in the greenhouse cultivating tomato. The light-emitting lamp type equipped to trap was blue, yellow, and white light-emitting lamp. The experiment results showed that trap equipped with blue light-emitting lamp captured the most number of $110{\pm}3.2$ adult whitefly and the number of captured adult whitefly was $71{\pm}1.4$ at yellow light-emitting lamp trap and $45{\pm}1$ at white light-emitting lamp trap respectively. The wavelength distribution band of blue light-emitting lamp was between 330 nm and 430 nm. The wavelength band of yellow and white light-emitting lamp contain repellent wavelength band at the same time. These results show that the trap equipped with blue light-emitting lamp could be used effectively for whitefly control and prevention in the greenhouse cultivating tomato.

• Korean Journal of Soil Science and Fertilizer
• /
• v.49 no.5
• /
• pp.503-509
• /
• 2016

To identify causes for drastic decrease in yield of tomato with repeated culturing number of the bag culture substrate of greenhouse tomatoes we investigated the physical and chemical properties of a coir used as the bag culture substrate to grow tomato at the Booyeo tomato experimental institute located in Booyeo, Chungnam Province for three years from 2012 to 2014. The results showed that total porosity ranged from 65.4 to 73.1% for the bulk densities of coir ranging from 0.12 to $0.14g\;cm^{-3}$. The volumetric water contents measured at 0.01 bar as air entry point were 25% (before), 33% ($1^{st}yr$), 45% ($2^{nd}yr$), and 37% ($3^{rd}yr$). Organic matter contents ranged from 82.0 to 96.2% (highest in $1^{st}yr$). pH and EC ranged from 4.47 to 6.47 (highest in $2^{nd}yr$), and from 22.2 to $53.5dS\;m^{-1}$ (highest in $1^{st}yr$) and cation exchange capacity ranged from 71.0 to $191.7cmol\;kg^{-1}$ (highest in $3^{rd}yr$). The surface structure observed with electrical microscope showed that the number of large pores decreased with increasing cultivating time while the proportion of smaller pores increased, indicating that the coir was consistently decomposed. Therefore, we could conclude that these changes of all physical and chemical properties of the coir may influence the holding capacities of water and nutrients, resulting in deterioration of quality of culture substrate of greenhouse tomatoes.

• Korean journal of applied entomology
• /
• v.58 no.3
• /
• pp.209-218
• /
• 2019

This study was conducted to develop a technology for environmentally friendly control of sweet-potato whitefly, Bemisia tabaci, by controlling their behavior using a push-pull strategy in a tomato greenhouse. B. tabaci was attracted the most by yellow color, light source of 520 nm, whereas it avoided the complex light treatment of 450 + 660 nm. The two natural enemies of B. tabaci, Cyrtopeltis tenuis and Orius laevigatus, were attracted the most by 520 nm light source. B. tabaci was repelled by the volatile organic compounds ocimene and carvacrol and was the most attracted by methyl isonicotinate. When buckwheat was added into the tomato greenhouse, the density of C. tenuis was maintained at about 16 times higher than when untreated for 15 days. As a result of the combined treatment of push-pull strategy, the density per trap of B. tabaci was three times lower than when no treatment was applied, and the control of this pest increased with time and reached up to 68.7%.

• Journal of Bio-Environment Control
• /
• v.31 no.1
• /
• pp.22-27
• /
• 2022

The attraction effects of light emitting diode (LED) trap to Spodoptera exigua and Spodoptera litura adults were evaluated in greenhouse and compared with those of no light trap, which is typical used in commercial trap. At this time, in order to attract these two species of moths, sex pheromone traps were installed at the top side according to the degree of tomato growth inside the tomato cultivation greenhouse around the LED trap. In addition, two types of light-emitting traps (420 nm, 470 nm) were installed in the greenhouse at 1/40 m², respectively. Also two sex pheromone were installed inside of the greenhouse according to the height of the tomato plants. 10 days later, Blue-light trap(BLB, 470 nm wavelength) was 3.1-3.5 times more attractive than Violet-light trap(VLB, 420 nm wavelength) in S. exigua (105.6 ± 7.3) and S. litura (42.0 ± 3.1) respectively, whereas the no-light trap was little attractive to S. exigua (33.7 ± 2.8) and S. litura (12.0 ± 1.5). On the other hand, after the installation of the sex pheromone trap and the LED trap, there was no damage to S. litura (Fabricius) and S. exigua in the pesticide-free area, indicating a high possibility of control. At this time, the operating cost of the two types of LED traps was 80 won/m² per unit area, and it was confirmed that both types of moths could be controlled. In addition, as a result of confirming the number of two types of moths caught in the sexual pheromone trap and two types of LED traps after 4 months, it was judged that eco-friendly control was possible as more than 373 moths/trap were attracted to the two types of moths.