• 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 Agricultural Science
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• v.41 no.2
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• pp.119-124
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• 2014

Feeding behaviors of the sweet potato whitefly, Bemisia tabaci, and changing of their feeding behaviors were recorded and analyzed with an Electrical Penetration Graph (EPG) analysis against cyantraniliprole. The characteristic patterns of feeding behaviors investigated were as follows; NP (non probing), pathway phase waveform, waveform of feeding xylem. In results, B. tabaci did not almost feeding the phloem. And It was not appeared potential drop during recording time. It was predominantly indicated pathway activity waveform and waveform of xylem feeding. After treatment of cyantraniliprole with recommended concentrations to tomato plants, EPG waveforms were recorded during 3 hours. Cyantraniliprole treatment showed longer time to first feeding xylem than untreated (P=0.043). It was showed shorter duration of first feeding xylem than untreated (P=0.017). And it was showed longer NP (non-probing) time than untreated. Consequently, It was supposed that cyantraniliprole was effect of anti-feeding or avoidance to B. tabaci.

• Korean Journal of Organic Agriculture
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• v.21 no.3
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• pp.363-372
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• 2013

This experiment was carried out for development of environment-friendly agriculture materials to control Bemisia tabaci (Gennadius) in eggplant. Plant growth investigated the spray at intervals of 7 days after transplanting on 8 environment-friendly agriculture materials, such as egg-yolk and cooking oil, Results were to be good in the control and neem products. B. tabaci population density adult and nymph was low at the dinotefuran WG chemical treatment, and also low neem products of environment-friendly agriculture material. We have investigated the effect of different concentration of neem products on B. tabaci population density. Yield was high in the dinotefuran WG, and hight in the neem products and papper seed oil, but low in the sophora extracts and Ginko net sarcocarp. In the case of neem products treatment indicated 52 percent yield more than control.

• 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.

• Korean Journal of Environmental Biology
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• v.41 no.4
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• pp.627-636
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• 2023

Bemisia tabaci Gennadius, one of the most invasive insect pests, has spread quickly nationwide since it was introduced to South Korea in 2008. The use of insecticides is the main management strategy for this pest, but the control efficiency has been decreased due to insecticide resistance. We collected 12 local B. tabaci populations to investigate the regional differences in efficiency and observed the mortality from 14 commercial insecticides applied at recommended concentrations (RC) and dilutions (0.1 RC and 0.01 RC) using the leaf dipping bioassay. Except for etofenprox (46-64%), thiamethoxam (37-60%), pyriproxyfen (21-61%), and pyridaben (61-65%), the other insecticides showed excellent insecticidal efficacy of 70% to 100% at their RC. In particular, flupyradifurone, emamectin benzoate, and cyantraniliprole showed high insecticidal efficacy of over 90% in all of the tested populations. Some insecticides that rapidly decreased in activity (less than 30%) at diluted concentrations or showed high resistance levels in nearby regions were classified for cautious use due to the possibility or potential to develop resistance. The results provide selected insecticides for B. tabaci control by region and could contribute to reducing insecticide abuse and increasing insecticidal efficiency in farming fields.

• 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.60 no.2
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• pp.167-173
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• 2021

Sweet potato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is an insect pest with sucking mouth part and globally attacks diverse crops and vegetables. Since first reported in 1998, it is now widely spread in many regions in Korea. Due to insecticide resistance, it is necessary for optimal control of the whiteflies to select effective insecticides with precise insecticide resistance monitoring. In this study, B. tabaci individuals were collected from 12 regions in 7 provinces of Korea from June to September in 2020. Using these field populations, insecticide resistance levels were monitored using a residual contact bioassay along with molecular markers. Bioassay results revealed that B. tabaci possessed high levels of resistance to five insecticides exhibiting different modes of action: dinotefuran, spinosad, emamectin benzoate, chlorfenapyr, and bifenthrin. In addition, quantitative sequencing in target sites of organophosphate and pyrethroid insecticides revealed that point mutations reached to saturated or near-saturated levels across the country. This suggests that insecticide resistance management is required for effective control of B. tabaci populations in Korea.

• Korean journal of applied entomology
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• v.52 no.1
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• pp.23-27
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• 2013

Investigations were conducted to prevent entrance of Bemisia tabaci (Gennadius) with very fine mesh nets. B. tabaci vectors tomato yellow leaf curl virus in tomatoes. B. tabaci could be completely prevented to penetrate into an 83 mesh net, though few of them passed the 60 mesh net. An independent 60 mesh net cage was built within one of the three interconnected common plastic greenhouse ($21.0{\times}18.3m$) in order to find its usefulness as a crop protection tool from insect pests. TYLCV infected tomato plants were not detected, though a few eggs of B. tabaci and mines of Liriomyza trifolii (Burgess) were detected locally at the entrance of the sliding door. There were practically no significant differences between treatments of nets and the conventional plant height, leaf length and width, number of floret clusters, sugar brix, and product yield. In viewpoints of commercialization, it could be considered highly prospectful to apply to the nets to glasshouses or other greenhouses in which the growing period of crops is long, if the nets were used in the openings of sides, ceilings, and entrances of the greenhouse. However, it might be necessary to take preventive measures for occurrences of insect pests living in soil, temporarily or permanently, as well as high humidity diseases.

• Korean Journal of Environmental Biology
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• v.38 no.4
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• pp.616-624
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• 2020

International trade is one of the primary ways that non-native species spread worldwide. Korea and China are geographically close and have a large mutual trade volume. To investigate the population movement of the invasive whitefly(Bemisia tabaci Gennadius) between the two countries, we compared the biotype distribution, insecticidal response, and the TYLCV(tomato yellow leaf curl virus) viruliferous rate of local populations collected in 2019. Based on the mitochondrial DNA COI sequences of B. tabaci, only the Q biotype was found in all populations in Korea, whereas the B biotype (14.3%) and Q biotype (85.7%) were found in China. In the haplotype composition of the B. tabaci Q biotype, only the Q1 group[Q1H1(79.8%) and Q1H2(20.2%)] was observed in China, but the Q1 group [Q1H1(1.7%) and Q1H2(97.5%)] and the Q2 group(only one individual) were found in Korea. The Korean populations showed high mortality(more than 80%) from 15 commercial insecticides, but the Chinese populations showed significantly low mortality from eight insecticides. No TYLCV infections were observed in the Korean populations while the average TYLCV viruliferous rate was 21.4% in the Chinese populations. Taken together, the results suggest that the population structures of B. tabaci in the two countries are different and may have different immigration histories.

• Korean Journal of Organic Agriculture
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• v.24 no.4
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• pp.809-819
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• 2016

This experiment was carried out to determine the treatment interval on neem product for control of Bemisia tabaci on eggplant using eco-friendly agriculture. We have investigated the control effect of B. tabaci, growth characteristics of eggplant, economics according to neem product treatment interval on eggplant. The longer neem processing interval tended to decrease control effect on nymphs of B. tabaci. Control effect of nymph of B. tabaci according to treatment interval of 3 days, 5 days, 7 days, 10 days, and 15 days were 96.7%, 89.7%, 76.1%, 73.4%, and 51.0%, respectively. This result was the same tendency in adult of B. tabaci control effects on eggplant. Growth characteristics of eggplant according to neem the treatment interval of 3 days, 5 days, and 7 days, was less damaged on of B. tabaci. However, the 10 days, 15 days, and untreated of neem treatment intervals were badly damaged by B. tabaci. Therefore, neem treatment interval of 3~7 days for control of B. tabaci was high control effect. However, it is considered to be the most suitable to process every seven days considering the economics and so on. The results of economic analysis from income of 7 days neem treatment interval was the most high as 19.505 thousand won per 10a and the most economical treatment for control of B. tabaci.