• Korean journal of applied entomology
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• v.29 no.1
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• pp.6-13
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• 1990

The banana insect pest species and their damages were surveyed from 9 vinyl hoses of Cheju Island on August in 18. A total of 5 pest species wre found ; banana root weevil (BRW) Cosmopolites sordidus Germar (Curculionidae) a wireworm Melonotus sp. (Elateridae), a spider mite teranychid sp. (Tetranychidae), mulberry mealybud Pseudococcus comstocki (Kuwana)(Pseudococcidae), and common cutworm Spodoptera litura (Fabricius)(Noctuidae). Among them, the BRW which attacked the rhizome of banana plant was newly recorded from Korea. It is assumed that the weevil would be introduced from Japan, Philippine or SriLan-Ka wiht the banana seedlings imported during early 1980's.

• The Korean Journal of Pesticide Science
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• v.15 no.4
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• pp.479-484
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• 2011

The number of comstock mealybug, Pseudococcus comstocki (Kuwana) suddenly increased at ginseng fields in Yangpyeong, Gyeonggi-do from mid July to early August. By the late of September just before digging up the roots of ginseng, more than 8 individuals of the comstock mealybug per plant were occurred and evenly dispersed around the roots. Through the bioassay in the laboratory, six environmental friendly agricultural materials (for example, Nobug, Kkagsami, GB-1, GB-2, GB-3, GB-5) containing sophora extract or paraffin oil as main components were selected by the effective control agents for controlling the comstock mealybug. These selected agents showed a quite similar insecticidal activities to 2 insecticides such as clothianidin and thiamethoxam registered in control of ginseng insect pests. Also. in the ginseng field test, the agent containing sophora extract and paraffin oil, like 2 insecticides showed high control effects against the comstock mealybug.

• Korean journal of applied entomology
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• v.53 no.3
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• pp.209-215
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• 2014

This study was performed to monitor the seasonal occurrence of Pseudococcus comstocki (Kuwana) by using pheromone traps and to test a mating disruption technique to control this pest in pear orchards. We compared the attractiveness of rubber septa loaded with 1.5 and 3.0 mg of the pheromone, 2,6-dimethyl-1,5-heptadien-3-yl acetate. A total of 1,021 and 1,431 males were caught in traps baited with 1.5 mg and 3 mg of the pheromone, respectively. The numbers of males caught were not affected by trap color, although yellow traps were more attractive than white traps. In 2012, P. comstocki males were captured between June and October, with peaks in late June, early August, and late September. In 2013, the males were trapped between June and October, with peaks in middle June, late July, and late September. In pheromone mating disruption tests, catches were reduced by 17.7, 65.3, and 62.9% in orchards treated with 450, 900, and 1,350 mg per 10 a of the pheromone, respectively. At harvest, 3.4, 2.9, and 4.8% of fruits in orchards treated with 450, 900, and 1,350 mg per 10 a were damaged by P. comstocki, while 9.5% were damaged in the control orchard.

• Korean journal of applied entomology
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• v.35 no.2
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• pp.119-125
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• 1996

Temperature-dependent development study for overwintered eggs of Pseudococcus comstocki (Kuwana) wasconducted to develop a forecasting model for egg hatch date. Hatch times of overwintered eggs were comparedat five constant temperatures (10, 15, 20, 25, 27$^{\circ}$C) and different collection dates. A nonlinear, four-parameterdevelopmental model with high temperature inhibition accurately described (R2=0.9948) mean developmentalrates of all temperatures. Variation in developmental times was modeled(~~=0.972w9)it h a cumulative Weibullfunction. Least-squares linear regression (rate=O.O06358[Temp.]-0.07566)d escribed development in the linearregion (15-25$^{\circ}$C) of the development curve. The low development threshold temperature was estimated 11.9"Cand 154.14 degree-days were required for complete development. The linear degree-day model (thermal summation)and rate summation model (Wagner et al. 1985) were validated using field phenology data. In degreedaymodels, mean-minus-base method, sine wave method, and rectangle method were used in estimation of dailythermal units. Mean-minus-base method was 18 to 28d late, sine wave method was 11 to 14d late, rectanglemethod was 3 to 5d late, and rate summation model was 2 to 3d late in predicting 50% hatch of overwinteredeggs. hatch of overwintered eggs.

• Korean journal of applied entomology
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• v.42 no.1
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• pp.43-51
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• 2003

This study was carried out to develop the forecasting model of Pseudococcus comtocki Kuwana for timing spray. Field phonology and temperature-dependent development of p. comstocki were studied, and its stage transition models were developed. p comstocki occurred three generations a year in Suwon. The 1 st adults occurred during mid to late June, and the 2nd adults were abundant during mid to late August. The 3rd adults were observed after late October. The development times of each instar of p. comstocki decreased with increasing temperature up to 25$^{\circ}C$, and thereafter the development times increased. The estimated low-threshold temperatures were 14.5, 8.4, 10.2, 11.8, and 10.1$^{\circ}C$ for eggs, 1st+2nd nymphs, 3rd nymphs, preoviposition, and 1st nymphs to preoviposition, respectively. The degree-days (thermal constants) for completion of each instar development were 105 DD for egg,315 DD for 1st+2nd nymph, 143 DD for 3rd nymph, 143 DD for preoviposition, and 599 DD for 1 st nymph to preoviposition. The stage transition models of p. comstocki, which simulate the proportion of individuals shifted from a stage to the next stage, were constructed using the modified Sharpe and DeMichele model and the Weibull function. In field validation, degree-day models using mean-minus-base, sine wave, and rectangle method showed 2-3d, 1-7d, and 0-6 d deviation with actual data in predicting the peak oviposition time of the 1st and 2nd generation adults, respectively. The rate summation model, in which daily development rates estimated by biophysical model of Sharpe and DeMichele were accumulated, showed 1-2 d deviation with actual data at the same phonology predictions.

• The Korean Journal of Pesticide Science
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• v.20 no.2
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• pp.133-137
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• 2016

In Korea, six mealybug species have been reported on pears. This study investigated the occurrence of mealybugs in 19 pear orchards from 2013 to 2014. Two species, Crisicoccus matsumotoi Siraiwa (Hemiptera: Pseudococcidae) and Pseudococcus comstocki Kuwana were mainly found. The dominant species was C. matsumotoi identified on 73% of infested fruit. Toxicities of 14 registered insecticides (Buprofezin+Acetamiprid EC, Buprofezin+Amitraz EC, Buprofezin+Clothianidin SC, Buprofezin+Dinotefuran WP, Buprofezin+Etofenprox WG, Buprofezin+Thiacloprid SC, Buprofezin+Thiamethoxam SC, Benfuracarb WG, Acetamiprid WP, Clothianidin SC, Dinotefuran WG, Thiacloprid SC, Thiamethoxam WG, Sulfoxaflor SC) commonly used to control P. comstocki were evaluated to C. matsumotoi nymphs and adults at the recommended concentration. As a results, all insecticides exhibited strong insecticidal activity with 100% mortality of both nymphs and adults. These results indicate that the 14 insecticides can be used in control for C. matsumotoi in field.