• Korean Journal of Organic Agriculture
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• v.25 no.4
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• pp.759-772
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• 2017

This experiment was conducted to develop control method for Bemisia tabaci (Gennadius) on eggplant using sticky trap method. According to the color of the sticky traps, the attractiveness of the B. tabaci was the highest in the yellow trap, followed by the green and orange. However, white, blue, red, black and green sticky traps have reduced attractiveness of B. tabaci. In order to improve the efficiency and attractiveness of sticky trap to the B. tabaci, the different kinds of sugars such as glucose, fructose, oligosaccharide, starch syrup and pure sugar were added to sticky traps respectively. However, the effect of B. tabaci attractiveness was low in starch syrup, pure sugar, and non-treated sticky traps. The attracting effect of B. tabaci was depending on the location of sticky trap. The highest value was obtained where sticky traps were located in the top of the eggplant, followed by 30 cm above from the top level. In addition, we were installed up to 40 sticky traps to determine the optimal amount of sticky traps to control B. tabaci in eggplant. When increasing the sticky traps, the number of adult and nymphs of B. tabaci were tended to be decreased significantly. This tendency was more effective in the latter stages than in the early stages. As the number of sticky traps increased, not only the growth rate of eggplant, leaf length, and stem diameter were to be better. But also number of fruits and product marketable value were increased at the early stage of growing as well. The study had proven that the sticky traps had an effect on increasing the yield at the early stage of growth, but the efficiency of controlling decreased due to the high density of B. tabaci of the next generation.

• 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 applied entomology
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• v.58 no.3
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• pp.203-207
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• 2019

Bemisia tabaci (Hemiptera: Aleyrodidae) is one of the major insect pests causing economic damages to over 900 different crops in the world. Especially, B. tabaci JpL (L. japonica) is known as a species living only in Japan and Korea so far, and mainly in Lonicera japonica and specific plant species. This study was conducted to investigate the occurrence and spread of B. tabaci JpL on Jeju Island in 2019. Of the total 25 areas surveyed, 1,003 individuals of B. tabaci JpL adults were collected from 24 L. japonica and one Conyza sumatrensis. All populations identified belonged to the JpL species. The result of this study showed that the population of B. tabaci JpL has increased at very high speeds to date compared to the previous reports in Korea.

• Korean journal of applied entomology
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• v.49 no.2
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• pp.129-137
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• 2010

Four major agricultural insect pests, Bemisia tabaci, Myzus persicae, Plutella xylostella and Tetranychus urticae, were irradiated with 30, 50, 70, or 100 Gy electron-beam. Longevity, egg hatching, emergence, and fecundity of the test insects were measured. Hatchability of B. tabaci, P. xylostella and T. urticae declined with increasing irradiation doses, and all B. tabaci and T. urticae eggs were dead at 100 Gy. When eggs of B. tabaci, P. xylostella and T. urticae were irradiated, hatch was inhibited. B. tabaci adults grown from 70 Gy irradiated eggs did not lay eggs. Fecundity of P. xylostella from the 100 Gy irradiated eggs decreased. When B. tabaci, P. xylostella, M. persicae and T. urticae nymphs/larvae were irradiated, the results were similar as those of the hatched eggs. When P. xylostella pupae were irradiated with 100 Gy, fecundity of emerged adults decreased and no eggs hatched. When B. tabaci, P. xylostella, M. persicae and T. urticae adults were irradiated with 70 and 100 Gy, fecundity decreased and egg hatch of B. tabaci was inhibited. However, the longevity of adults did not change and electron-beam irradiation of all developmental stages had no effect on the longevity of adults.

• Korean journal of applied entomology
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• v.39 no.1
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• pp.5-12
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• 2000

The sweetpotato whiteflies, Bemisia tabaci(Gennadius), were found recently in Korea on Glycine max, Euphorbia pulcherrima, and Rosa hybrida. The biotype identity of Bemisia tabaci in Korea was determined by several DNA markers including the random amplified polymorphic DNAs, and restriction fragments length polymorphism of mitochondrial 12S and 16S rRNA genes. The electromorph profiles of DNA fragments from the rose(Jincheon) and poinsettia(Seoul) populations in Korea are both identical to those of B biotypes distributed in Australia, Israel, and Japan. The populations of B. tabaci collected on Glycine max, Ipomea batatas, and Perilla frutescens in different localities retained the same DNA markes with the population from Lonicera japonica and shikoku of Japan. These populations are non-B biotype and considered as an indigenous type in the Far Eastern Asia Region including Korea and Japan, Morphological Characteristics of B. Tabaci were also observed by the scanning electron microscope and described with the comparison to the other important whitefly pest, Trialeurodes vaporariorum (Westwood).

• Korean journal of applied entomology
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• v.53 no.4
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• pp.465-472
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• 2014

The tobacco whitefly, Bemisia tabaci, infest the Oriental melon and give significant economic damage along with its virus-vectoring activity. Various biotypes of B. tabaci have been well known and are classified depending on the severity of crop damage and insecticide susceptibility. In this study, B. tabaci adults were collected in the melon fields located in Poongchun-myeon, Andong, Korea and diagnosed on their biotypes using PCR molecular markers. From the all the 11 greenhouses, B. tabaci biotype Q was identified. In addition, biotype B adults were also found from the 4 greenhouses. These results report the first occurrence of B. tabaci at the Oriental melon farms in Gyeongbuk province with mixed infection by the two biotypes in the area.

• Korean journal of applied entomology
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• v.53 no.4
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• pp.375-380
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• 2014

The sweetpotato whitefly (SPW), Bemisia tabaci Gennadius, is a major pest in tomato greenhouses on Jeju Island because they transmit viral diseases. To develop practical sampling methods for adult SPWs, yellow-color sticky traps were used in commercial tomato greenhouses throughout the western part of Jeju Island in 2011 and 2012. On the basis of the size and growing conditions in the tomato greenhouses, 20 to 30 traps were installed in each greenhouse for developing a sampling plan. Adult SPWs were more attracted to horizontal traps placed 60 cm above the ground than to vertical trap placed 10 cm above the plant canopy. The spatial patterns of the adult SPWs were evaluated using Taylor's power law (TPL) and Iwao's patchiness regression (IPR). The results showed that adult SPWs were aggregated in each surveyed greenhouse. In this study, TPL showed better performance because of the coefficient of determination ($r^2$). On the basis of the fixed-precision level sampling plan using TPL parameters, more traps were required for higher precision in lower SPW densities per trap. A sequential sampling stop line was constructed using TPL parameters. If the treatment threshold was greater than 10 maximum adult SPWs on a trap, the required traps numbered 15 at a fixed-precision level of 0.25. In estimating the mean density per trap, the proportion of traps with two or more adult SPWs was more efficient than whole counting: ${\ln}(m)=1.19+0.90{\ln}(-{\ln}(1-p_T))$. The results of this study could be used to prevent the dissemination of SPW as a viral disease vector by using accurate control decision in SPW management programs.

• Korean journal of applied entomology
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• v.56 no.2
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• pp.107-120
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• 2017

Bemisia tabaci (Hemiptera: Aleyrodidae) is one of the most important insect pests in the world. In the present study, the taxonomic status of B. tabaci and the number of species composing the B. tabaci complex were determined based on 550 COI gene sequences of B. tabaci. Genetic divergence within B. tabaci ranged from 0% to 27.8% (average 11.1%). This result indicates that the B. tabaci complex is composed of multiple species that may belong to different genera or subfamilies. A phylogenetic tree constructed based on 217 COI gene sequences without duplications revealed that the B. tabaci complex is composed of a total of 43 putative species, including a new species, Java. In addition, genetic divergence within nine species (Australia, Asia II 1, Asia II 6, Asia II 7, Asia II 10, Mediterranean, New world, New world 2, Sub Saharan Africa 1) indicates that 4.0% is reasonable to be used as a threshold of species boundaries within the B. tabaci complex, and species with high intraspecific genetic divergences can be related with cryptic species.

• Korean journal of applied entomology
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• v.54 no.4
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• pp.311-316
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• 2015

This study was performed to ascertain the potential of egg plant for use as a trap plant to attract Bemisia tabaci adults compared to that of tomato. Choice tests were conducted to compare the preference of B. tabaci adults to horseweed, egg-plant, cucumber, and tomato. B. tabaci adults were found to be more sensitive to visual cues than to odor cues, and they preferred the egg-plant and cucumber to horseweed. The attraction rates of the egg-plant and cucumber to B. tabaci adults were 82.3% and 82.5% respectively, compared to that of tomato. Because egg-plants are easier to manage compared to cucumber, we excluded cucumber from subsequent experiment. The attraction rate of egg-plant to B. tabaci adults was >90% when the height of egg-plant was equal or more than that of the tomato plant.

• Korean Journal of Organic Agriculture
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• v.22 no.3
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• pp.435-444
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• 2014

This experiment was carried out to develop an environmental friendly agriculture material (EFAM) using neem extract i.e. azadirachtin (0.5%), especially against Bemisia tabaci (Gennadius) in eggplant. Neem product was found to be very effective against both nymph and adult of B. tabaci. Yield and economic value of eggplant treated with neem extract were higher than other EFAMs used. Effect of different concentration of Neem product was also investigated on population density of B. tabaci. The growth and yield of eggplants were highest in plants treated with 500 times concentrated solution of neem product. Economic analysis showed that the income increased by 13,545 thousand won/10a from the plots treated with 500 times concentrated solution of neem product over control. The results suggested that 500 times concentrated solution of EFAM (azadirachtin 0.5%) could be a good controlling agent of B. tabaci in eggplants.