• Korean journal of applied entomology
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• v.43 no.3 s.136
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• pp.257-262
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• 2004

Toxicities of 51 pesticides (25 insecticides, 11, acaricides, 11 fungicides and 4 adjuvants) commonly used to control greenhouse insect, mite, and disease pests were evaluated to minute pirate bug, Orius strigicollis nymphs and adults at the recommended concentration. Among 25 insecticides tested, fipronil, lufenuron, acetamiprid+fipronil, $\alpha$-cypermethrin+flufenoxuron and buprofezin + amitraz showed low toxicity to O. strigicollis. Among acaricides, acequinocyl, bifenazate, chlorfenapyr, etoxazole, fenpyroximate, flufenoxuron, milbemectin, spirodiclofen and tebufenpyrad showed low toxicity to O. strigicollis. All fungicides and adjuvants tested were very low toxicity. It may be suggested from these results that five insecticides, nine acaricides, eleven fungicides and four adjuvants could be incorporated into the integrated thrips management system with O. strigicollis in greenhouses.

• Korean journal of applied entomology
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• v.34 no.4
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• pp.295-299
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• 1995

This study was conducted to find the control methods, status of overwintering and seasonal occurrence of Erioccoccus largerstroemiae on persimmon trees in Ch'ondo area, Kyongbuk province in Korea. Usually, overwintering eggs were sheltered in bark, among them the rate of alive eggs was 28.7%. The activiation of garpe-myrtle scale showed from late April, and they have three generations per year. The first occurrence of larval stage of Erioccoccus largerstroemiae starts from late June to early July, the second occurrence begins from middle August to late August, and from late June to early July, the second occurrence begins from middle August to late August, and from middle September to late September is the third, thus, three peaks of occurrence revealed in early July middle August, and late September respectively. Average number of eggs conceived in female adult was 229.3. Spray effect of chemical control showed as follows; lime sulfur with tow applications of pesticides (late June, late August) at 97.8%, machine oil with tow applications of pesticides (late June, late August) at 96.8%. And during the growing period, the spray results using three applications of pesticide only (late June, late August, amid September) showed 77.2% in field condition.

• Korean journal of applied entomology
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• v.53 no.2
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• pp.185-191
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• 2014

Corythucha marmorata (Uhler) belonging to the family Tingidae (Hemiptera) has been reported in Korea. In 2013, surveys were conducted to study its morphological characteristics, geographical distribution, and host plants. The adult is brown white and 2.77-3.28 mm in length, and the mature nymph is yellowish brown. Heavily infested trees appear yellowish white because they are fed on by the nymphs on the under surface of host plants. C. marmorata were found between early June and late October, and their numbers peaked in early July to late August. In 2013, the occurrence of C. marmorata was confirmed in 27 cities and counties nationwide, and 8 families and 24 species of host plants were identified. C. marmorata feeds on the following major host plants: Conyza canadensis, Aster pilosus, Helianthus annuus, Artemisia princeps, Rudbeckia bicolor, and Solanum melongena.

• Korean journal of applied entomology
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• v.20 no.1 s.46
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• pp.15-20
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• 1981

To analyze the inheritance of emergence rate of brown plant hopper (Nilaparvata lugens) biotypes, six crosses among biotype 1, biotype 2 induced by rearing on Mudgo and biotype 3 these on ASD 7, were made. Each generation $(P_1,\;P_2,\;F_l\; F_2,\;BC_1,\;BC_2)$ of each cross was fed on the rice seedlings of Mudgo and ASD 7 varieties. The emergence rate of biotpe 2 on Mudgo was controlled by the one incomplete dominant gene in $biotype\;l{\times}biotype$ 2 coross, however, that of biotype 3 on ASD 7 was controlled by one incomplete recessive gene in $biotype\;l{\times}biotype$ 3 cross. The genes involved in biotype 2 and biotype 3 were not identical, however, their allelic relations are not clear.

• Korean journal of applied entomology
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• v.22 no.1 s.54
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• pp.41-44
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• 1983

In order to evaluate the technique of P-32 labelling method for screening lines of rice to whitebacked planthopper, the relationship between the amount of ingestion and feeding preference of insects were observed with the resistant and susceptible lines where characteristics were predetermined by comparing their feeding preference and antibiosis method. The feeding preference of the insects was significantly correlated with the amount of P-32 ingestion. It was more manifest in adults than nymphs of the whitebacked planthopper. The density of nymph and radioactivity of P-32 were high in the susceptible line. This suggested that deforming the ingestion amount of P-32 in the insects seemed to be useful technique for accurate screening. For this technique, the uniform labelling of P-32 on the rice seedings was prerequisite and the uniformity was increased by triming roots and leaves in the length and number.

• The Korean Journal of Mycology
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• v.39 no.3
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• pp.256-258
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• 2011

This study was conducted to investigate agents inducing conidial germination of an entomopathogenic fungus, Beauveria bassiana KK5. Different chemicals including carbohydrates were mixed with conidia of B. bassiana and incubated on water agar for 12 hours. Fructose, mannose and skim milk were useful for spore germination compared to other chemicals. Bioassays against green peach aphids were conducted with the fungal conidia suspended in 1% fructose, mannose and skim milk. Of them, a mixture of skim milk plus conidia of B. bassiana KK5 showed the highest mortalities against $3^{rd}$ instar of green peach aphid.

• Korean journal of applied entomology
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• v.55 no.4
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• pp.523-528
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• 2016

The migratory locust Locusta migratoria, one of the world's most notorious insect pests, has polyphenic (gregarious or solitarious) characteristics. Although this species is known to have several morphological variants, it is genetically divided into two different lineages using mitochondrial genome analysis: Southern (Africa, Southern Europe, Southern Asia, and Australia) and Northern (East Asia and the Eurasian continent). In 2014, a large number of orange black-colored gregarious L. migratoria nymphs suddenly appeared at Haenamgun, Jeollanamdo in the south of Korea. This is the first report of gregarious phase locusts occurring in Korea. In this study, mitochondrial COI sequences of one nymph and 11 adults of L. migratoria were analyzed to examine the genetic lineage of the gregarious nymphs of L. migratoria. Our results showed that all 12 individuals belong to the Northern linage and have low intraspecific genetic divergences (0.0% - 0.9%).

• The Korean Journal of Ecology
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• v.22 no.1
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• pp.31-37
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• 1999

The developmental process of Paracolopha morrisoni's galls on Zelkova serrata until the emergence of alatae from the galls was studied at Chonju, Korea. The galls were formed from late April to early May, 1997 and the galls began to open in early June. The length and width of galls and leaves were measured during the period from gall formation to opening. The length and width of galls have been increased until mid May continuously. The galls stopped growing at 12th of May. Fundatrices (the first generation in the gall) began to larviposit from May 15th and the second generation developed in late May. The alatae of the second generation arrived at the final stadium, that was escaped from the gall, in early June. Thus, there were only 2 generations in the gall. The close correlationship between gall growth and leaf growth suggests that leaf growth force may have a great influence on gall development.

• Korean journal of applied entomology
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• v.40 no.3
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• pp.253-258
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• 2001

Biological control of thrips with Orius strigicollis Poppius was evaluated in a hot pepper greenhouse. To study the biological control strategy of thrips on hot pepper grown in greenhouse, three plots were established: natural enemy removed plot(CNT), pesticide treated plot(PAT) and O. strigicollis released plot with no pesticide application (NRT). The nymphs of O. strigicollis were found on the leaves of lower stratum in CNT and NRT at 13 days after the first release. The density of thrips was suddenly dropped and maintained at low level since 15 day after transplanting in NRT. The densities of thrips on hot pepper flowers was also maintained at much less level in NRT than in CNT. The thrips and O. strigicollis, which were aggregated in flowers, may have resulted in improved predator searching. Average damage indices of CNT, PAT and NRT were 0.31, 0.05 and 0.08 and the percentage of damaged fruit were 80.0, 17.1 and 24.8% respectively. The damage index and percentage of damaged fruit of NRT was slightly higher than PAT, but very lower than CNT. The introduction of the adults of O. strigicollis, which was the biological control agent for the control of thrips, was effective on hot pepper.

• Korean journal of applied entomology
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• v.36 no.2
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• pp.166-171
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• 1997

To find out an alternative prey of Orius strigicollis Poppius in the laboratory continuous rearing system, cotton aphid (Aphis gossypii), two spotted spider mite (Tetmnychus urticae) and mold mite (Tyrophagus putrescenriae) were tested as alternative prey. Development and oviposition of 0. strigicollis were observed at 25f l0C, RH 60-80% and 16L:8D. Survival rate and developmental period of the nymphal stages of 0. strigicollis was 81. 6% and 11.6 days when fed on cotton aphid, 56.796, 14.6 days, 42.3% and 16.5 days when fed on two spotted spider mite and mold mite, respectively. Total oviposition of 0. strigicollis was 68.5 eggslfemaie fed on cotton aphid, 46.1 and 26.5 eggsifemale fed on two spotted spider mite and mold mite, respectively. Cotton aphid seems to be most suitable prey for rearing 0 . strigicollis among the three prey species tested.