• Korean Journal of Agricultural Science
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• v.42 no.2
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• pp.81-86
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• 2015

Three genes selected from cDNA library of tobacco whitefly, Bemisia tabaci, were checked whether these genes expressed in plant or not, and confirmed the change of gene expression using qRT-PCR in the tobacco whitefly. First of all, three genes were inserted in Tobacco rattle virus (TRV) RNA2 vector using Sac I and Xho I restriction enzymes, and conducted agro-infiltration in tobacco plants (Nicotiana benthamianana). And then, it was confirmed that TRV RNA2 vector and genes inserted in TRV RNA2 vector were expressed in plant. So, after feeding the tobacco whitefly the plants inoculated the genes and induced RNAi of the genes, we plan to confirm the RNAi in the whitefly and investigate the changes of gene expression through the qRT-PCR.

• International Journal of Industrial Entomology and Biomaterials
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• v.3 no.1
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• pp.51-56
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• 2001

Field experiments were conducted to find out the effec- tive control measures with some bases alone and in combination with Dichlorvos and Dimethoate for the whitefly Aleuroclava sp. Singh in the mulberry garden. Four common bases marketed in India Soda, Sunlight, Nirma and Surf at 1% concentration and their synergists with 0.02% Dichlorvos and 0.03% Dimethoate applied to mulberry plants reduced the whitefly by 46-95% (adults) 50-90% (nymphs) upto 15 days of application. Amongst the bases 1% Soda is more effective but, the mixing of 0.02% Dichlorvos with 1% Surf found more effective than 0.02% Dichlorvos With 1% Soda solution. As Surf and Dichlorvos mixture is costly for the control of whitely, Soda was found better (in combination with Dichlorvos) as it is cheaper and easily available to the farmers.

• 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 Organic Agriculture
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• v.25 no.3
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• pp.631-642
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• 2017

For effective control of insect pest which can outbreak in a field during crop cultivation, various control agents such as eco-friendly agricultural materials (EFAM) including microbial control agents and chemical pesticides have been applied at fields and these control agents may be treated simultaneous or sequential in the same field to suppress diverse pests and diseases. The agents may influence each other and control efficacy may also differ from interactions. Therefore we need to test compatibility of microbial control agents with other agricultural agents. In this study, we investigated influence of pre-treated EFAMs, which are registered for whitefly control in greenhouse, on germination, mycelial growth and control efficacy of Isaria javanica isolate against sweet potato whitefly. The results showed that a mixture of paraffin oil+cinnamon oil among 4 EFAMs highly reduced germination ($8.9{\pm}1.3%{\sim}24.5{\pm}0.9%$) and mycelial growth ($0.81{\pm}0.01cm{\sim}0cm$) of I. javanica. To investigate the effects of the treatment interval between EFAMs and I. javanica on sweet potato whitefly control, four different EFAMs were pre-treated 0, 1, 4, and 7 days before applying I. javanica. Pre-treatment of four EFAMs inhibited insecticidal activity of I. javanica against sweet potato whitefly. Therefore when EFAMs and a mycopesticide using I. javanica spray simultaneous or sequential, application of EFAMs need more than 7 days interval after treatment of mycopesticide at field.

• Korean journal of applied entomology
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• v.59 no.4
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• pp.411-416
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• 2020

Whitefly populations found in heated tomato greenhouses were monitored across three locations in Korea (Nonsan and Buyeo, Chungnam Province; Iksan, Jeonbuk Province) from November to May during the 2015 -2018 growing seasons. From May to October, surveys were conducted in Jangsu (Jeonbuk Province), where retarding cultivation was performed. Whitefly populations were classified and quantified by location and year. The dominant species were Trialeurodes vaporariorum (Westwood) and Bemisia tabaci (Gennadius). The species populations were mixed, but the frequency of occurrece of B. tabaci was higher than that of T. vaporariorum. Although whitefly populations started to increase in late March, they sharply increased in May and the highest population density was observed at the end of the harvest season. Therefore, the management of greenhouse tomato whiteflies through monitoring should begin in early March. In the case of retarding cultivation, the management of whitefly populations should be implemented in June, before the density of whitefly populations increases.

• Horticultural Science & Technology
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• v.29 no.5
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• pp.420-432
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• 2011

Population dynamics of greenhouse whitefly, Trialeurodes vaporariorum (Westwood), were modeled and simulated to compare the temperature effects of air and tomato leaf inside greenhouse using DYMEX model simulator (pre-programed module based simulation program developed by CSIRO, Australia). The DYMEX model simulator consisted of temperature dependent development and oviposition modules. The normalized cumulative frequency distributions of the developmental period for immature and oviposition frequency rate and survival rate for adult of greenhouse whitefly were fitted to two-parameter Weibull function. Leaf temperature on reversed side of cherry tomato leafs (Lycopersicon esculentum cv. Koko) was monitored according to three tomato plant positions (top, > 1.6 m above the ground level; middle, 0.9 - 1.2 m; bottom, 0.3 - 0.5 m) using an infrared temperature gun. Air temperature was monitored at same three positions using a Hobo self-contained temperature logger. The leaf temperatures from three plant positions were described as a function of the air temperatures with 3-parameter exponential and sigmoidal models. Data sets of observed air temperature and predicted leaf temperatures were prepared, and incorporated into the DYMEX simulator to compare the effects of air and leaf temperature on population dynamics of greenhouse whitefly. The number of greenhouse whitefly immatures was counted by visual inspection in three tomato plant positions to verify the performance of DYMEX simulation in cherry tomato greenhouse where air and leaf temperatures were monitored. The egg stage of greenhouse whitefly was not counted due to its small size. A significant positive correlation between the observed and the predicted numbers of immature and adults were found when the leaf temperatures were incorporated into DYMEX simulation, but no significant correlation was observed with the air temperatures. This study demonstrated that the population dynamics of greenhouse whitefly was affected greatly by the leaf temperatures, rather than air temperatures, and thus the leaf surface temperature should be considered for management of greenhouse whitefly in cherry tomato grown in greenhouses.

• 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.40 no.4
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• pp.327-335
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• 2001

In order to establish a whitefly control system using conventional groups of insecticide(carbamate, organophosphorus and pyrethroid insecticides), three alternative application methods were designed on the medium growth stage of cucumber. To discriminate the effectiveness of these sequences observed were the residual activity of insecticides, frequency of insecticide applications, residue of insecticides in cucumber leaves, development of insecticide resistance in whitefly, and yield of fruits. Spraying furathiocarb, a carbamate insecticide, was very effective in reducing the frequency of application for the control of white flies. The effectiveness of furathiocarb was enhanced by the potentiation process to carbofuran, the long residual activity, and the lower development rate of insecticide resistance. Methion, an organophosphorus insecticide, did not show resistance development after successive use but resulted in short residual activity. However, other organophosphates, profenofos and phenthoate, lost their activity by the resistance development. Decreasing activity was common to pyrethroids, deltamethrin and zetacypermethrin due to resistance. From these results it could be drawn a conclusion that furathiocarb, a carbamate insecticide, was the most desirable among conventional insecticide groups for the management of greenhouse whitefly population on the cucumber. To prevent an outbreak of the insect pest by various cause, it was recommended to choose acetamiprid, a nicotinoid, which showed very good control efficacy to the resistance insects to conventional insecticides.

• 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.

• The Korean Journal of Applied Statistics
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• v.17 no.3
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• pp.403-418
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• 2004

Recently space-time model in spatial data analysis is widly used. In this paper we applied this model to analysis of greenhouse whitefly. For handling time component, we used ARMA model and autoregressive error model and for outliers, we adapted Mugglestone's method. We compared space-time models and geostatistic model with MSE and MAPE.