• Journal of Bio-Environment Control
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• v.21 no.2
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• pp.120-126
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• 2012

Two experiments were designed and executed to measure the effectiveness of the two-fluid fogging system in controlling whiteflies in tomato cultivation. The two-fluid fogging system that lowers temperature and raises humidity in greenhouses provides an eco-friendly method of preventing damages from whiteflies. The first experiment elucidated the effect of fogging treatment on the elimination of whiteflies and investigated the sectional distribution of whiteflies. The second experiment analyzed the vertical distribution, the motility of whiteflies and reduction of the number of whiteflies under the fogging system. The result of the experiments showed that the fogging system lowered the number of whiteflies and decreased their motility significantly. It affected the vertical distribution of whiteflies as well. Based on these experiments, we strongly recommend using the fogging system to prevent and control whiteflies in greenhouses, in addition to installing yellow sticky traps in the areas that have the highest density of whiteflies.

• Korean Journal of Organic Agriculture
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• v.21 no.1
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• pp.95-104
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• 2013

This research was performed to test the effects of oleic acid for the management of greenhouse whiteflies and tobacco whiteflies. Tobacco whiteflies, especially, are the vectors of tomato yellow leaf curl virus on tomato plants. Whiteflies are not only the vectors of various viruses but also the major insect pests that cause direct damages through sucking and induce sooty mold with their sweet dew on tomato plants. There are many eco-friendly management measures including the use of yellow sticky trap and natural enemies such as Eretmocerus eremicus and Amblyseius swirskii. However, these management measures have difficulties to implement in the greenhouse. Therefore, in this research, oleic acid was tested for its effect on the management of whiteflies at various concentrations of 1,000ppm, 2,000ppm, or 4,000ppm. As a result, treatments of 1,000ppm, 2,000ppm and 4,000ppm oleic acid showed the control value of 70%, 76% and 84%, respectively. In another test, treatments of 2,000ppm oleic acid, and control treatment of 1,5000ppm neem oil and 50ppm dinotefuran showed the control value of 82%, 75%, and 75%, respectively. Cost for one application of oleic acid and neem oil for 10a area would be 3,180 Won and 20,150 Won, respectively. As a result, it was assumed that the use of oleic acid would be a appropriate management measure.

• Journal of Microbiology and Biotechnology
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• v.12 no.1
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• pp.145-148
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• 2002

The virulence of five Verticillium lecanii strains against greenhouse whiteflies, Trialeurodes vaporariorum, was tested at various temperatures as a major environmental factor. Strain CS-626 was found to be the most durable strain at a broad temperature range, and highly virulent against greenhouse whiteflies in a detached-leaf bioassay. In a tomato plant pot experiment, the $LT_{50}\;and\;LC_{50}$ of the CS-626 strain were 6.2 days and $2.3{\times}10^6$ conidia/ml, respectively. The optimal concentration of CS-626 for successful infection was $1{\times}10^8$conidia/ml. These results indicate that the CS-626 strain of Verticillium lecanii has a strong potential for effectively controlling greenhouse whiteflies.

• Current Research on Agriculture and Life Sciences
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• v.30 no.2
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• pp.115-123
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• 2012

Whiteflies harbor several secondary endosymbionts, which are maternally inherited from mother to offspring, that have major effects on host preferences, biology, and evolution. Here, we identified Wolbachia bacteria in sweetpotato whitefly (Bemisia tabaci) as well as whitefly popluations from other countries by comparison of 16S rDNA sequences. Wolbachia were detected in all tested indigenous B. tabaci populations (Bangladesh, Myanmar, Nepal, and the Philippines) as well as Q1 biotype of Korea, whereas they were absent from B biotype of Korea and Q biotype of China. Wolbachia were also detected in all five tested Aleurodicus dispersus populations as well as Tetraleurodes acaciae, whereas they were not detected in all seven Trialeurodes vaporariorum populatuions. In addiiton, Wolbachia were detected in parasitic wasp (Encarsia formosa) of B. tabaci as well as honeybee (Apis mellifera). Among the 19 whitefly populations from different countries, our analysis identified four phylogenetic groups of Wolbachia, thereby demonstrating the high diversity of this genus. Wolbachia phylogeny suggests a correlation of geographical range with ecological variation at the species level.

• Journal of Bio-Environment Control
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• v.21 no.2
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• pp.114-119
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• 2012

We have conducted 4 experiments to develop the most environmental and effective use of the two-fluid fog system to prevent and exterminate whiteflies in tomato cultivation. In particular, these experiments used Vitamini tomatoes grown in stand-alone greenhouses at Buyeo Tomato Experiment Station as subjects. Each experiment utilized the fog system in a different way. The first experiment provided the control group, which was subject to the two-fluid fog system without additional humidity control. In the second experiment, the two-fluid fog system controlled the humidity level to be above 70%. The third and the fourth experiment utilized natural substances, which were 1.5 mg/L of Neem Oil and 2 mg/L of Oleic acid respectively, without additional humidity control. From the first experiment, we could observe that a simple use of the two-fluid fog system decreased the density of whiteflies in the greenhouses. This impact of the fog system on whiteflies was greater in the second experiment. By comparing the first and the second experiment, we concluded that whiteflies are more effectively prevented by maintaining a higher humidity level via the fog system's smaller water droplets that float in the air for longer time than the standard fog system in rather dry condition. In the third and the fourth experiments, the extermination level was 78% and 76.4% respectively, comparing only 53% in the first experiment without the humidity control. Therefore, using the natural substances in addition to the humidity control increases the extermination effectiveness. Considering the similar results from the 3rd and the 4th experiments, Oleic acid has a greater appeal for its lower price. Using the two-fluid fog system to both control the humidity on a daily basis and spray the substances for occasional extermination would reduce labor cost and increase production in an environmental way.

• Korean journal of applied entomology
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• v.49 no.1
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• pp.1-4
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• 2010

Aleuroclava aucubae (Kuwana) and Aleuroclava euryae (Kuwana) are newly recorded in the Korean fauna of whiteflies (Aleyrodidae). A key to species of Aleuroclava is also provided with illustrative photographs.

• Korean Journal of Organic Agriculture
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• v.20 no.4
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• pp.643-654
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• 2012

We conducted the experiment in order to evaluate the control effect of whitefly using the sticky trap. Both Bemisia tabaci and Trialeurodes vaporariorum were more attracted to yellow sticky trap than white or blue colored traps. When yellow sticky traps were installed in different height around tomato, catches of B. tabaci were not significantly different among the traps and catches of T. vaporariorum on the traps in the upper position were more than lower position. T. vaporariorum was more attracted to trap when host plant is smaller. The attracted number to yellow sticky traps were not significantly different between whiteflies (B. tabaci and T. vaporariorum) and their parasitoids (Encarsia formosa and Eretmocerus mundus). Yellow sticky trap reduced population density of both B. tabaci and T. vaporariorum by more than 80% on tomato nursery in a screen cage. Population density of whiteflies in greenhouse installed yellow sticky traps was less than one third of that in untreated greenhouse.

• Journal of Bio-Environment Control
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• v.20 no.4
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• pp.394-398
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• 2011

The effect of two-fluid fogging system on the control of Bemisia tabaci in tomato cultivation was evaluated in a greenhouse. The number of Bemisia tabaci was decreased by 87% from the fog treatment for 7 days. During the fog treatment, the mean daily temperature was decreased by $2^{\circ}C$ and the mean daily relative humidity was increased by 3~4% as compared to the non-treatment. The reduction of Bemisia tabaci in the treatment might not be resulted from the differences in temperature and humidity in the greenhouse. The sound coming from the two-fluid fogging system did not affect when it was operated without water inside. Therefore it was concluded that water droplets coming out the nozzle reduced the growth and the movement of whiteflies because the suspension of tiny water droplets were attached on the skin of whiteflies.

• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.2
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• pp.203-205
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• 2003

Black sooty mould fungus was observed on the upper side of the mulberry leaves caused by the Capnodium sp. This fungus develops with the utilization of the honeydew dropped by the whiteflies. Few selected insecticides like Monocrotophos, Chloropyriphos and Nuvan were tried to control the whitefly incidence and followed by the application of Maida (wheat flour paste) and Starch solution separately to control the incidence of the Capnodium on mulberry. It is found that a significant control of the whitefly incidence with the application of Nuvan (2 $m\ell$/L) and followed by Chloropyriphos (2 $m\ell$/L) and Monocrotophos (1.6 $m\ell$/L) and also a significant control of sooty mould infection were recorded with Starch and Maida application.

• Korean journal of applied entomology
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• v.51 no.2
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• pp.163-170
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• 2012

Aleurolobus marlatti (Quaintance), Massilieurodes formosensis (Takahashi), and Pealius rhododendri Takahashi were found for the first time in Korea. This study provides a brief summary and photographs of the major characters of these species and an updated identification key to the whitefly species known to occur in Korea.