• Korean journal of applied entomology
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• v.35 no.2
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• pp.137-139
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• 1996

The sycamore lace bug, Corythucha ciliata (Say), attacking a sycamore tree, Platatanus orientalis L., was first found in Korea, and was widely distributed in the central part of the country. The adult was milky white in color and 3.0-3.2 mm long, and the matured nymph was black. Heavily infested trees appear yellowish white as a result of feeding by the nymphs on the under surface of leaves.

• The Korean Journal of Pesticide Science
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• v.3 no.2
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• pp.74-80
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• 1999

These studies were carried out to investigate the effects of nonsteroidal ecdysone agonist, tebufenozide on embryonic and postembryonic development of sycamore lace bug, Corythucha ciliata. Tebufenozide exhibited ovicidal activity($LC_{50}=4.0$ ppm). Susceptibility of each instar nymphs to tebufenozide was nearly same($LC_{50}=2.3{\sim}6.0$ ppm). The tebufenozide treatment in the final instar affected the emergence, longevity and fecundity of surving adults significantly. Tebufenozide applied at high concentration (10 ppm) to younger adults delayed prioviposition period, and decreased adult longevity, the number of eggs laid per female and hatchability. The treatment also inhibited the ovarian development of the female adults.

• Journal of Korean Society of Forest Science
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• v.96 no.1
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• pp.58-64
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• 2007

Overwintering adults of sycamore lace bug (Corythucha ciliata) infected by an unidentified pathogenic fungus were found on the stems of street trees of sycamore in Cheongju city. The objective of this study was to describe this entomopathogenic fungus infecting overwintering sycamore lace bug adults. This unidentified fungus colonized the insect adult body and formed white colony with subglobose clusters of conidiocarps. The size of conidiocarps was 300 to $400{\mu}m$ and each conidium was 15 to $20{\mu}m$. The conidiospore was globus and 2.5 to $3.0{\mu}m$ in diameter, and the hyphae were 1 to $5{\mu}m$ thick. This fungus was successfully isolated and cultivated on potato dextrose agar medium (PDA). The fungal colony was white and then became light yellow. When conidia from this pure culture were inoculated into the overwintering adults, the fungus formed conidiocarps with the same morphology on the insect body and the lethal rate by the fungus was $88{\pm}16%$. This fungus has over 99% homology with Cordyceps bassiana (imperfect fungal name is Beauveria bassiana) in ITS-5.8s rDNA base sequence. The fungal ecology and the infection process of the fungus into its host need to be clarified before using this fungus as a biological control agent.

• Journal of Korean Society of Forest Science
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• v.88 no.4
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• pp.555-561
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• 1999

The development of sycamore lace bug, Corythucha ciliata, had been studied at four constant temperature levels of 15, 20, 25, and $30^{\circ}C$. And characteristics of its oviposition were studied at field. Developmental periods of eggs were 39.1, 17.1, 9.8, and 8.0 days, those of nymphs were 58.5, 23.8, 14.5, and 10.8 days, hatchabilities of eggs were 42.0, 78.5, 83.3, and 78.7%, and survival rates of nymphs were 14.7. 60.5, 75.7, and 48.9% at different temperatures of 15, 20, 25, and $30^{\circ}C$. Lower development threshold temperature and the effective accumulative temperature above the threshold required to complete development from egg to nymph were $11.5^{\circ}C$ and 344.8 degree days, respectively. The optimum temperature was estimated to be $25^{\circ}C$ for developments of egg and nymph. The longevities of adults were 41.0 days and 37.0 days for female and male, respectively.

• Korean journal of applied entomology
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• v.38 no.2
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• pp.117-121
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• 1999

Development and reproduction of the sycamore lace bug, Corythucha ciliata, were investigated under different temperature regimes. Duration of development from egg to pre-adult of the sycamore lace bug measured seven temperatures ranged from 54.0 days at 18$^{\circ}$C to 17.9 days at 33$^{\circ}$C. Development was not successful at 15$^{\circ}$C and 35$^{\circ}$C. Developmental zero point and total effective temperature for development of egg, nymphal, and complete development were 1 1 .O, 10.9, ll.l$^{\circ}$C and 150.3, 230.6, 376.1 degree-days, respectively. Longevities of adult females varied to temperature from 51.8 days at 18$^{\circ}$C to 17.2 days at 33$^{\circ}$C. The average fecundity per female was greater at 25$^{\circ}$C and 28$^{\circ}$C compared with at other temperatures. The intrinsic rate of natural increase (r,) and net reproduction rate (R,) were highest at 28$^{\circ}$C as 0.170 and 73.25, respectively. As a result, optimum ranges of temperature for C. ciliata growth were between 25$^{\circ}$C and 28$^{\circ}$C.

• Journal of Life Science
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• v.10 no.2
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• pp.164-168
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• 2000

To understand the biological characteristics of Corythucha ciliata occurring in Korea, developmental periods and its susceptibility to several insecticides were examined under growth chamber condition at $25^{\circ}C$. It took 11.1 day from egg to hatch. And duration of each stage up to the 5th nymph after hatching was 4.0, 2.1, 2.0, 2.9, and 4.0 days, respectively. Total duration from egg to adult was 26.1 days, preoviposition period was 12.2 days, and average number of eggs laid by a female was 83.0. Sex ratio of female was 51.6% and lifespan of female adult was 43.2% days. LC50 value of deltamethrin and esfenvalerate were 0.8 and 0.9 ppm, respectively. Insecticidal effects were better in pyrethroids than organophosphates and carbamates.

• Journal of Life Science
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• v.17 no.6 s.86
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• pp.828-830
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• 2007

To determine the effects of newly developed insecticide (Ultra) on Sycamore lace bug (Corythucha ciliata), ten leaf discs were sprayed with the Ultra solution including the other selected commercialized insecticide solutions such as Carbaryl and Pirimicarb, and also with a water-sprayed control. According to the results, the control effect of Ultra on the adults and immatures was respectively 98.9% and 97.5% after 48hr, and the corresponding values were higher than that of the other tested insecticides (i.e Carbaryl showed 84.6% for adults and 85.6% for immatures; Pirimicarb showed 83.0% for adults and 90.7% for immatures). For the Susceptibility test, LC$_{50}$ value of Ultra showed the lowest as 1.5ppm, the value of Carbaryl and Pirmicarb were 3.7 ppm and 30.4 ppm, respectively. Therefore, the insecticidal effects were better for the newly developed insecticide than the commercialized insecticides.

• Journal of Korean Society of Forest Science
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• v.89 no.3
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• pp.384-388
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• 2000

For the control of Corythucha ciliata, the insecticidal activity of five commercial pesticides (Monocrotophos 25%SL, Phosphamidon 50%SL, Imidacloprid 20%DC, Thiamethoxam 15%DC and Acetamiprid 20%SL) were examined with trunk injection method in Seoul, Sanbon and Chungju. The insecticidal activity of five commercial pesticides was >88%. The insecticidal activity of Monocrotophos maintained 31 days later after trunk injection when treated leaves were supplied to this pest. This result indicates that one application of trunk injection is enough to control this pest, and this method can save the control cost compared with ground application which should be applied two or three times per year to control this pest. To make the model of treatment dosage at each D.B.H class (cm), $1.0m{\ell}/DBH$, $1.5m{\ell}/DBH$ and $2.0m{\ell}/DBH$ pesticide dosage was used. At <20cm, the insecticidal activity of $1.0m{\ell}$ dosage was >95%, and $1.5-2.5m{\ell}$ dosage was needed for the effective control at 30~50cm. More than $2.5m{\ell}$ dosage was effective at >50cm. Spray method was used in laboratory to select pesticides for ground application. Three commercial pesticides (Ethofenprox 20%EC, Ethofenprox 10%WP and Cyfluthrin 1%EC) were used, and all pesticides showed >95% insecticidal activity.