• Korean journal of applied entomology
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• v.58 no.4
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• pp.313-317
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• 2019

Stink bugs (Hemiptera: Pentatomidae) are economically important pests of fruit trees in Korea. The aim of the present study was to survey the relative abundance of stink bugs on four stone fruits, maesil (Prunus mume Sieb. et Zucc), cherry (Prunus avium L.), plum (Prunus salicina Lindl), and peach (Prunus persica (L.) Batsch), from 2017 to 2019 in the field. Four stink bug species were observed, including Carbula putoni (Jakovlev), Dolycoris baccarum (L.), Halyomorpha halys (Stål), Plautia stali Scott. H. halys was the most abundant (65%), followed by P. stali (26%), C. putoni (7%), and D. baccarum (2%). H. halys was the dominant species in maesil, cherry, and peach fruits, whereas P. stali was the dominant species in plum fruits. Most (81%) of the stink bugs observed were adults, with nymphs accounting for only 19% of the observed specimens. More stink bugs were observed during the late season than during the early season. These finding suggest that control strategies should be developed for the management of H. halys and P. stali at harvest in stone fruit tree orchards in Korea.

• Korean journal of applied entomology
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• v.12 no.4 s.17
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• pp.139-142
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• 1973

Experiment was conducted to study resistance of rice varieties and lines originated from Korea and IRRI-sources to the white-backed planthopper, Sogatella furcifera Horvath. The nature of varietal resistance to the insects was evaluated from the viewpoints of nymphal period and adult emergence. The varieties Colombia, Muthumanikam and Pankhari-203 were resistant, the varieties CO-22, Mudgo and Vellailangalayan moderately susceptible, the other varieties all susceptible. Nymphal period and rate of adult emergence were significantly different according to the degree of resistance of the rice varieties. Nymphal period was short (about 10 days) in the susceptible varieties and long (about 14-16 days) in the resistant varieties. The .ate of adult emergence was significantly lower in the resistant varieties than in the susceptible varieties. The lower rate of adult emergence in the resistant varieties may be due to the fact that the insects were suffered higher nymphal mortality in the resistant than in the susceptible varieties.

• Korean journal of applied entomology
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• v.18 no.1 s.38
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• pp.15-21
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• 1979

To determine the population regulation mechanism of the Green rice leafhopper (Nephotettix cincticeps Uhler), the responses of the population increase to initial densities and the effect of host conditions and temperatures during developmental period were investigated. In the out door experiment, the increasing ratio of population density of this pest was reduced as initial density increased and this density-dependent effect was differ in accordance with host condition. Host conditioning through feeding resulted in reduction in numbers of eggs produced and it seemed to be affected by some inhibiting materials secreted by the pest during feeding. though the direct effect of feeding can't be excluded. The population growth was related with population density and host stage. Thus in late planted units, the host stage was favourable to the growth of population at low initial insect density but unfavourable at relatively high initial insect density and in early planted units, vice versa. The temperature during developmental stages definitely affected the determination of sex ratio of adult population and reduced numbers of eggs produced. The most favourable temperature to the population increase was $290^{\circ}C$, and at high temperature, $33^{\circ}C$, severe reduction of fecundity was shown ana it seemed to be caused by the simple reduction in numbers of eggs produced.

• Korean journal of applied entomology
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• v.11 no.2
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• pp.61-68
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• 1972

This study has been carried out to investigate the varietal resistance of Tong-il rice variety (IR-667) at the seedling stage to the brown planthopper. Nilaparvata lugens STAL, and further to know the biological effects of the varieties to the insects. The results obtained were as followings; 1. Tong-il variety tested in this experiment was susceptible to the brown planthopper but it seemed to be a little more tolerable than the Japonica varieties which had been recommended in Korea. 2. Tong-il variety (Suwon 213, Suwon 213-1, Suwon 214, and Suwon 215) was highly prefered by brown planthopper for feeding to the Korean recommended varieties Paltal, Jinheung, Akibare, and Shin #2. 3, The resistant varieties Mudgo, Kayama MGL-2, and Karsamba ASD-7 which showed low feeding preference exhibited higher ovipositional preference than the susceptible varieties. Relatively greater number of eggs was recorded on the Tong-il variety (Suwon 213, Suwon 213-1, and Suwon 215) in comparison with the Korean recommended varieties, 4, When the female brown planthopper adults were caged on Tong-il variety (Suwon 214) and the resistant variety Karsamba ASD-7 separately, greater number of eggs were observed on Suwon 214 and less on Karsamba ASD-7, while when two varieties Suwon 214 and Karsamba ASD-7 were given together in the same cage, Karsamba ASD-7 was much more prefered for oviposition to Suwon 214. 5. There was no difference in e99 Periods and their hatchal\bility between the resistant and susceptible varieties, but nymphal periods, rate of adult emergence, longevity of the adult, and its fecundity were significantly different according to the varieties.

• Korean journal of applied entomology
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• v.47 no.1
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• pp.31-36
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• 2008

The embryonic and postembryonic developments of Nezara antennata Scott were observed in 5 different rearing cages such as A (Cylindrical, ${\phi}\;10cm{\times}4cm$), B (Cylindrical, ${\phi}\;14.5cm{\times}2.8cm$), C (Rectangle, $6.5L{\times}6.5cmW{\times}10cmH$), D (Cylindrical, ${\phi}$ 9cm in bottom & ${\phi}$ 11.5 cm in $upper{\times}10.8cm$) and E (Cylindrical, ${\phi}\;15cm{\times}7.5cm$) containing soybean and peanut seeds as food, and sponge soaked with water under laboratory condition of $24^{\circ}C$ and 15L : 9D. Hatchability ranged from 93 to 97%. Nymphal duration was shortest of 6 days in the 1st instar and longest of 10 days in the 5th instar. The nymphal duration was 38 to 39 days observed in the rearing cages. Emergence rate was in the range from 53 to 62% with highest in A and B cages. Adult longevity was 65 to 75 days for male, and 67 to 74 days for female, and was longest in the B cage. Total number of eggs laid by female adult was in the range from 51 to 56 without significant difference in the rearing cages, and was the most in the B cage. Accordingly, the reproductive rate of N. antennata for 1 generation was within 25 to 33 times, and was highest in the B rearing cage. Therefore, it could be concluded that B cage is most suitable for stable rearing of N. antennata under laboratory condition.

• Korean journal of applied entomology
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• v.39 no.2
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• pp.73-82
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• 2000

Two Psyllidae species of Cacopsylla pyricola (Foerster) and C. pyrisuga (Foerster)damaging pear trees have been reported in Korea. However, their ecological characteristics and damagepatterns have not been evaluated yet. To establish basic control measures of C. pyricola, field phenology,overwintering ecology, seasonal fluctuation and temperature-dependent development of C. pyricola wereexamined. C. pyricola overwintered under the bark scale of pear trees as winter form adults and theymoved to fruiting twigs from mid-February. Honeydew produced by C. pyricola nymphs and adults asthey feed caused serious black sooty mold on leaves and fruits. The seasonal occurrence of C. pyricolawas different every year. In 1993, characterized by cold temperature and heavy precipitation, C. pyricolapopulation was maintained highly during growing season. However, the population was decreased rapidlyfrom early July in 1994, year of hot and dry weather condition. In 1995, year of average temperature, thedensity of C. pyricola population was decreased during hot months of July and August, and rebuilt up inSeptember and October. The development periods of C. pyricola eggs were 13.33 days at 15"C, 9.32 daysat 20$^{\circ}$C, 7.82 days at 25"C, 6.60 days at 30$^{\circ}$C, and 7.75 days at 35$^{\circ}$C. The development periods ofnymphs were 33.75 days at 15OC, 23.77 days at 20$^{\circ}$C, 15.21 days at 25"C, and 17.40 days at 30$^{\circ}$C. Theirdevelopment periods and mortalities were increased in higher temperatures. The parameters of nonlineardevelopment model, Weibull and linear development models of Cacopsylla pyricola were estimated.models of Cacopsylla pyricola were estimated.

• Korean journal of applied entomology
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• v.51 no.2
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• pp.131-140
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• 2012

The hawthorn spider mite, Tetranychus viennensis, is a pest of apples and a quarantine pest from some countries that import apples from Korea. A controlled atmosphere and temperature treatment system (CATTS) was developed as an alternative disinfestation method to methyl bromide fumigation treatment, and has been applied to control various insects and other arthropod pests on fruits. We applied CATTS to disinfect T. viennensis under conditions that were previously developed to control the peach fruit moth, Carposina sasakii. First, T. viennensis was sampled from Japanese apricot, Prunus mume, and identified by its morphological characters. In addition, both cytochrome oxidase I (COI) and internal transcribed spacer (ITS) sequences supported the morphological identification. Second, the heat-tolerant developmental stage was determined in T. viennensis. When a $46^{\circ}C$ heat treatment was applied to egg, nymph, and adult stages of T. viennensis, adults were the most tolerant stage. Third, when heat temperature was used along with 1% $O_2$ and 15% $CO_2$, the mites showed a significant increase in susceptibility to the heat treatment. Finally, CATTS at $46^{\circ}C$ with 15% $CO_2$ and 1% $O_2$ for 30 min resulted in 100% mortality of all T. viennensis development stages. These results indicated that CATTS isapplicable to disinfest T. viennensis in post-harvest apples.

• Korean journal of applied entomology
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• v.48 no.4
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• pp.503-508
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• 2009

Biological-control-based-integrated-pest-management of major pests occurring on sweet pepper in greenhouse during summer season was tried. As many as 2.1 Orius laevigatus per $m^2$ were released in two times on June 6 and 19, and the population of thrips was kept under control and accordingly the damage was negligible throughout the season. To control aphids, a total of 0.8 Aphidius colemani per $m^2$ were released in four times, 0.2 of them at a time, flonicamid on May 14 and July 18 and pymetrozine on June 14 and September 4 were sprayed on the spots of high aphid occurrence to reduce the release of the wasp, and the density of aphids was kept under control. Whitefly was controlled successfully by releasing a total of 343.4 Amblyseius swirski per $m^2$ in nine times, 38.1 of them at a time, from May 9 until November 12 and dinotefuran was sprayed on November 12 when the density of whitefly increased up to 200 per trap. Tetranichus kanzawai was controlled by both Phytoseiulus persimilis which was released a total of 44.4 per $m^2$ in five times 8.9 of them at a time from May 23 to September 10, and the A. swirski which was released for the control of whitefly.

• Korean journal of applied entomology
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• v.48 no.4
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• pp.423-429
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• 2009

Characteristics of habitat alteration and post-embryonic development of Paratlanticus ussuriensis were investigated in the mountain region of Bitanri, Yeongdong county, Chungcheongbuk-do from 2007 to 2009. Overwintered eggs under the ground in the hillside were hatched from late March to early April. The soil temperature during this season was $7{\sim}14^{\circ}C$. Young nymphs lived mainly at the hillside by eating oak tree leaves but the 3rd or 4th instars switched their habitat to orchards near the hillside in early May, which is the time for sprouting of peach leaves. Old nymphs developed into the adult stage at the orchards in late May and moved back to the hillside in late June. Duration of post-embryonic development from the first instar nymph to adult was 49.2 days after 7 moltings at $25^{\circ}C$. Female adults collected from the field had long ovipositor (26.2 mm) and were slightly longer in the body length, hind femur, tegmen and pronotum than those of males.

• Korean journal of applied entomology
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• v.53 no.4
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• pp.391-398
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• 2014

This study investigated inhibitory doses of electron beam and X-ray irradiation by comparing their effects on the development and reproduction of four insect pests (Myzus persicae, Tetranychus urticae, Liriomyza trifolii, and Frankliniella intonsa). When M. persicae nymphs were irradiated with 100 Gy of electron beam and 30 Gy of X-ray beam, offspring production by adults that developed from the treated nymphs was completely inhibited. When M. persicae adults were irradiated with 200 Gy of electron beam and 50 Gy of X-ray beam, emergence of the $F_1$ generation was inhibited. However, these two ionizing radiations did not affect adult longevity. When T. urticae eggs were irradiated with 150 Gy of electron beam and 50 Gy of X-ray beam, egg hatching was completely inhibited. When L. trifolii pupae were irradiated, the emergence rate decreased with increasing doses of X-ray irradiation. After F. intonsa adults were irradiated with 250 Gy of electron beam and 200 Gy of X-ray beam, egg hatching of the $F_1$ generation was completely suppressed.