• Horticultural Science & Technology
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• v.28 no.6
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• pp.990-995
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• 2010

This study was conducted to compare differences in fruit quality by harvest time of 'Fuji' apple fruit that was frozen on tree by unusual low temperature in that air temperature was under $-3.5^{\circ}C$ for 7 hours. Fruits were harvested at 1 day before, and 2 days and 6 days after freezing damage, respectively. Harvest's soluble solid contents in all treatments was over $14^{\circ}Bx$. Firmness and titratable acidity of fruit harvested after freezing damage was lower than those of fruit harvested before freezing damage. During cold storage, ethylene production of fruit harvested after freezing damage was higher than that of fruit harvested before freezing damage. The reduction in the level of fruit quality during cold storage of fruit harvested after freezing damage was more serious than that of fruit harvested before freezing damage. The reduction of fruit quality during subsequent ambient temperature for 1 week after cold storage of fruit harvested after freezing damage was higher than that of fruit harvested before freezing damage. In comparison of treatments that were harvested at different times after freezing damage, ethylene production and reduction in the level of fruit quality until 8 weeks of cold storage of fruit harvested at 6 days after freezing damage was lower than that of fruit harvested at 2 days after freezing damage. However, this difference by harvest time after freezing damage disappeared after 8 weeks of cold storage. Incidence of flesh browning was not affected by freezing at air temperature under $-3.5^{\circ}C$ for 7 hours.

• Korean journal of applied entomology
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• v.49 no.4
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• pp.299-304
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• 2010

The striped fruit fly, Baetrocera scutellata (Diptera: Tephritidae), is one of the most important pests in Cucurbitaceae plants. Among 6 attractants for B. scutellata used, Cue-lure was shown better effect than the others. Newly emerged adult of B. scutellata had been occurred early June of the year tested. There were two peaks of occurrences of B. scutellata, one was from mid-July to early August and the other was early September suggesting that B. scutellata has two generation a year. The larva of B. seutellata damaging the female flower and stem of the pumpkin was found for the frist time on Korea. The blossoms were damaged and fallen by B. scutellata which were 53.8% of male flower and 30.7% of female flower in the 6 pumpkins. The pumpkin flowers were damaged 51.9% by B. scutellata. Especially thc pumpkin flowers damaged were shown 72.7% (1015/1397 individuals) from August to September. The larva of B. scutellata was found from the Trichosanthes kirilowii on 24 June 2009 in Jinan-gun Jeollabuk-do.

• Korean journal of applied entomology
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• v.52 no.4
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• pp.365-370
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• 2013

The plume fruit moth, Grapholita dimorpha Komai, a fruit tree pest occurring in the northeast Asia, was firstly reported to infest apple in Korea in 2009, but its direct damage to other fruit trees has been poorly studied. In this study, we investigated shoots and fruits of both peach and plum trees and compared their damage rates by G. dimorpha to those by G. molesta, a congeneric species. In order to discriminate the two moth species, we developed a molecular diagnosis method using species-specific primer sets on different PCR conditions and distinguished the two species collected from the damaged shoots or fruits. The shoots and fruits of peach were infested mostly by G. molesta. However, in plums, the shoots were damaged by G. molesta and the fruits mostly by G. dimorpha. In addition, these two species showed a clear difference in host preference in fruit damage, where 92.5% of the Grapholita moths collected in peach fruits were identified as G. molesta, but 97.0% of the moths in plum fruits were G. dimorpha. The difference of the damage between the two fruit trees may give important information for monitoring of the two moth species in these orchards.

• Korean journal of applied entomology
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• v.40 no.2
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• pp.117-123
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• 2001

The occurrence and damage by the oriental fruit moth, Grapholita molesta (Busck) were investigated on pear trees from 1996 to 2000 in the Naju, Korea. The number of overwintering larvae in pear trees considerably varied depending on the maturation time of varieties. The density of overwintering larvae on late cultivars such as Gamcheonbae and Okusankichi was high, but relatively low on early cultivars. Trunk and main branch of pear trees were main overwintering sites. In 1997, overwintering larvae began to pupate from middle February, and to emerge from late March. Male moths were caught in the sex pheromone traps from late March until early October with four peaks of flight in 1996~2000. In every generation larvae damaged both the shoots and fruits of pear tree, but the first and second generation larvae tended to damage mainly shoots, while most of the injured fruits were due to the third and fourth generation larvae. In pear fruits damaged by fruit moths, most of these were caused by oriental fruit moth larvae and none of pear fruits were damaged by peach fruit moth or pear fruit moth larvae in 1998~2000.

• Korean journal of applied entomology
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• v.53 no.4
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• pp.491-495
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• 2014

Mites were collected from organic cultivations of greenhouse cucumbers and identified as Tyrophagus neiswanderi (Acari: caridae). T. neiswanderi (length, $490.1{\mu}m;$ width, $288.1{\mu}m$) is a very small, milky-white, and egg-shaped mite, and it mainly causes damage to the leaves, flowers, and fruits of cucumber plants. In the early growing season of cucumbers, the shoots of seedlings became pale and yellow because of T. neiswanderi, and eventually shrinkage or bud-failing was observed in the plants. In the middle of the growing season, T. neiswanderi caused white spots on the leaves and flowers of the plants, and the spots gradually became holes. T. neiswanderi also caused severe damage to young fruits by feeding on the rinds of the fruits, inducing malformations and lowering the economic value.

• Korean journal of applied entomology
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• v.50 no.3
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• pp.203-208
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• 2011

This study was conducted to evaluate Geometridae (Lepidoptera) species as pests and the damage they cause in citrus orchards in Jeju, Korea. Seven geometridae species occurred in citrus orchards: Ascotis selenaria, Ectropis excellens, Menophra senilis, Biston panterinaria, Ourapteryx nivea, Odontopera arida and Hypomecis punctinalis. Among them, A. selenaria was most abundant, followed by E. excellens and M. senilis. Most Geometridae larvae fed on citrus leaves, but A. selenaria larvae ate fruits and leaves. Fruit damage of Citrus unshiu appeared as gnawed scars caused by young larvae feeding on fruit surface. Fruit damage on Shiranui fruits appeared as a wide hole or deep scars caused by feeding by mature larvae (6th instar). Citrus leaves damage due to Geometridae larvae was high during May to June. Fruit damage started in late June as the spring-shoots of citrus hardened and increased sharply in late July. In the field experiment, fruit damage in the late season reached 4.2% in both 2008 and 2009 and reached 5.2% in 2010. In citrus orchards, A. selenaria larvae started to appear in mid-May and their populations peaked in mid June, late July, and early to mid-September. Adult males of A. selenaria had a maximum peak in mid-May, and two other peaks in early to late July and late August to early September. A. selenaria male adults were collected in a pheromone traps constantly throughout Jeju Island.

• Agrochemical news magazine
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• v.19 no.4 s.145
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• pp.26-29
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• 1998

• Korean journal of applied entomology
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• v.55 no.4
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• pp.359-376
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• 2016

Increase in world trade commodities along with climate change entails frequent pest insect invasions from subtropical to temperate zones. Tephritidae is one of two families in fruit flies along with Drosophilidae and consists of more than 5,000 species. Some tephritid flies in genera Anastrepha, Rhagoletis, Ceratitis, and Bactrocera are highly invasive and give serious economic damages on fruits and vegetables in temperate zones. This review focuses mainly on Bactrocera fruit flies, which have been well studied in control techniques to defend their invasion and colonization. Though various control techniques against Bactrocera fruit flies have been developed, less efforts have been paid to establish efficient integrated pest management (IPM) programs. This review introduces current control techniques of fruit flies and some successful IPM programs implemented in subtropical islands. In addition, major fruit flies infesting crops in Korea have been also reviewed in their occurrence and control programs.

• 농업기술회보
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• v.49 no.3
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• pp.37-38
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• 2012

우박에 의한 배 과수원의 피해가 매년 발생하고 있으나, 피해 후 이듬해 수세회복을 위한 연구결과가 부족하여 농가에 어려움을 주고 있다. 과실생장 초기인 6월초에 우박피해를 받은 배 과수원의 피해 정도에 따라 충실한 꽃눈을 확보할 수 있는 기술을 알아본다.

• Korean journal of applied entomology
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• v.52 no.1
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• pp.45-51
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• 2013

Tropical plants of mango(Mangefera indica), dragon fruit(Hylocereus undatus), and atemoya(Annona cherimola ${\times}$ A. squamosa) are cultivated in Jeju, Korea. A pest survey on those tropical fruits was conducted from 2008 to 2011. Major pests of Mango were thrips, aphid, mealybug, and lepidoptera species. Thrips palmi and Scirtothrips dorsalis were the most important pests in mango fields. T. palmi mainly injured the leaf but S. dorsalis injured the leaf and fruit. Lepidoptera mango pests injured leaves but some larva of Adoxophyes honmai injured fruit surface around the stem. Aphid pests, Aphis gossypii and Myzus persicae, injured the shoots and Pseudococcus kraunhiae occurred on the stem and fruit. Ant species, A. gossypii, and S. litura, were important pests on dragon fruit. Ants and aphid occurred and injured the stem, flower, and fruit. Spodoptera litura larva severely injured the stem. Among the atemoya pests, S. litura and Homona magnanima caused severe damage.