• Korean journal of applied entomology
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• v.45 no.2 s.143
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• pp.145-152
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• 2006

Predation of Neoseiulus fallacis was observed for biological control of Panonychus citri that is one of the major insect pests on citrus. The daily predation of development stages of P. citri by an adult female of N. fallacis were 20.1 eggs, 26.1 larvae, 18.2 protonymphs, and 7.4 deutonymphs at 25$^{\circ}C$, The daily predation of P. citri eggs by N, fallacis was observed under different temperatures. The predation was increased as the temperature rise. At this time, ratio of eggs production of l! fallacis after predation of P. citri eggs (number of eggs N. fallacis/number of eggs P. citri consumed by N. fallacis) was 0.09. The daily predation of P. citri eggs by N, fallacis was 21.1, 17.3, and 16.7 on the different arenas (diameter: 20, 40, and 60 mm), respectively. The predation was decreased as the arena of the leaf increase. The functional response of M fallacis to P. citri showed Holling's Type II response: the consumption of prey by N. fallacis increased as the density of prey increase but increasing rate was gradually reduced. As the result, it seemed that N. fallacis can be use for biological control of P. citri.

• Korean journal of applied entomology
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• v.42 no.3
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• pp.233-240
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• 2003

The effect of density suppression of Amblyseius fallacis (Garman) against Panonychus citri (McGregor) on citrus tree introduced with some different ratio was investigated. When it was introduced with over 16:1 (Panonychus citri: A. fallacis) ratio, Panonychus citri was suppressed very effectively. And in case of introduced once or two times with 20: 1 ratio when the density of Panonychus citri was reached 0.5 and 1.0 per leaf, the density of A. fallacis was formed highly, but the suppression effect against Panonychus citri was not effective. Also, the density changes of P. citri and A. fallacis on the citrus tree released with 10: 1 ratio (P. citri: A. fallacis) when the density of P. citri was reached about 0.1 per leaf in plastic film house were investigated. In case of released twice at the interval of 10 days, the density of A. fallacis was high and P. citri was suppressed so effectively over two month. On the inside of canopy of the citrus tree planted in plastic film house, the air temperature was much lower than on the outside of canopy, while relative humidity was much higher.

• Korean journal of applied entomology
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• v.39 no.1
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• pp.13-19
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• 2000

This studies was carried out to investigate the natural enemies of citrus red mite, pononychus citri and seasonal occurrence of its major beneficial insects in Yuzu groves (Chonnam province) from 1996 to 1998. Natural enemies against citrus red mite were 9 species including Oligota kashmirica benifica, 0. yasumatsui, Stethorus punctillum, Chrysopa pallens, Propylea japonica, Orius sauteri, Scolothrips takahashii, Amblyseius womersleyi and one unidentified species of thrips (Family: Phlaeothripidae). Among them, Oligota kashmirica benzficu and Stethorus punctillum were found to be dominant species. 0 . kushmirica henifica had 4-5 generations from middle May to middle November with peak in early September. S. punctillum had 3 generations from late May to late October with peak of late June to middle July. Population dynamics between predator ( 0 . kushmiricu benifica and S. punctillum) and prey (Panonychus citri) were quite well synchronized until September but predator density was decreased abruptly after October.

• Landscaping Tree
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• s.107
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• pp.18-20
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• 2008

일본이 원산지이며 제주도에서는 과수로 그리고 내륙의 도심지에서는 실내 정원수, 분재 등으로 인기가 매우 높다. 6월에 흰색의 꽃을 피우며 길이는 2cm로 짙은 향기가 있다. 9월에 구형의 열매가 녹색을 띠며 10월에는 황색의 열매가 우리의 마음을 안정하게 해준다. 귤은 꽃, 설익은 녹색 열매, 질 익은 황색 열매 모두가 짙은 향기를 가지고 있어 인기가 높다. 특히 늦은 겨울에도 열매를 볼 수 있어 적막한 도시민의 정서에 도움을 주는 과수이다. 이러한 귤을 가해하는 해충으로 깍지벌레류와 진딧물류의 피해가 심하며 이들에 대한 생태 및 방제법을 간략하게 소개하고자 한다.

• Korean journal of applied entomology
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• v.40 no.3
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• pp.197-202
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• 2001

The density of citrus red mite(CRM), Panonychus citri(McGregor), on the commercial satsuma mandarin Citrus unshiu L. groves were determined by counts of the number of CRM per leaf using by leaf sample in Jeju for 2 years. Binomial sampling plans were developed based on the relationship between the mean density per leaf(m) and the proportion of leaf infested with less than T mites per leaf($P_{T}$), according to the empirical model $ln(m)={\alpha}+{\beta}ln(-ln(1-P_{T}))$. T was defined as tally threshold, and set to 1, 3, 5 and 7 mites per leaf in this study. Increasing sample size, regardless of tally threshold, had little effects on the precision of the binomial sampling plan. Increasing sampling size had little effect on the precision of the estimated mean regardless of tally thresholds. T=1 was chosen as the best tally threshold for estimating densities of CRM based on the precision of the model. The binomial model with T=1 provided reliable predictions of mean densities of CRM observed on the commercial satsuma mandarin groves. Binomial sequential sampling procedure were developed for classifying the density of CRM. A binomial sampling program for decision-making CRM population level based on action threshold of 2 mites per leaf was obtained.

• Korean journal of applied entomology
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• v.51 no.3
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• pp.207-213
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• 2012

The cryptic mealybug, Pseudococcus cryptus, has been increasingly damaging citrus, particularly those plants grown in plastic greenhouses. This study was conducted to monitor the seasonal phenology of adult male cryptic mealybugs and to determine the timing for control using a sex pheromone trap. Adult males responded to a synthetic sex pheromone and trap color. An increasing number of males were attracted to the traps with increasing concentrations of sex pheromone up to 5 mg. The males occurred annually four times and had three cohorts at a time due to different overwintering developmental stages. After overwintering the adult males began to in mid-late April. A positive correlation was observed between the number of adult males caught in traps and the mean density per twig of all motile stages except first stage nymphs of the cryptic mealybugs. The peak time for the first nymph to occur was estimated from the maximum attraction time of the males, and the cumulative degree days (DD) was 350 DD, similar with the preoviposition period.

• Journal of Applied Biological Chemistry
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• v.57 no.2
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• pp.141-144
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• 2014

The effects of electron beam irradiation on control of Myzus persicae and Planocococcus citri (Risso) were evaluated with the changes of mortality, emergence rate, fecundity, and egg hatchability. As a result of this study, M. persicae and P. citri (Risso) was not directly affected by electron beam irradiation with low doses (30, 60, 90, and 120 Gy) but the irradiation had effects on inhibition of development and reproduction of the pests.

• Korean journal of applied entomology
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• v.40 no.2
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• pp.105-109
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• 2001

Dispersion pattern of the citrus red mite (CRM), Panonychus citri (McGregor) was determined to develop a monitoring method in the satsuma mandarin fields, Citrus unshiu L., in Jeju-do, during 1999 and 2000. CRM population was sampled by collecting leaves. Taylor's power law provided better description of mean-variance relationship for the dispersion indices compared to Iwao's patchiness regression. Slopes and intercepts of Taylor's power law from leaf samples did not differ among surveyed groves. Fixed-precision levels (D) of a sequential sampling plan were developed using Taylor's power law parameters generated from all motile stages of CRM in leaf sample. This sampling plan for leaf sample estimate was tested with resampling validation for sampling plan using 4 independent data sets. Resampling simulation analysis demonstrated that actual fixed-precision level values were better than desired D values of 0.20, 0.25 and 0.30. Required numbers for tree sampling at the density of more than 7 mites per tree were fewer than 18.

• The Korean Journal of Mycology
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• v.28 no.1
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• pp.49-54
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• 2000

This study was conducted to investigate the major mycotoxins occurred during storage from apple, peat, citrus and grape. Analyses of the mycotoxins were conducted by TLC and HPLC. Patulin was only detected from apple, pear, citrus and grape infected by penicillium mycotoxins, but citrinin did not detected. The detected amount except grape ranged from $5.68{\sim}46.81\;{\mu}g/g$ in apple, $3.48{\sim}84.7\;{\mu}g/g$ in pear, $0.16{\sim}0.27\;{\mu}g/g$ in citrus, respectively. When compared to the effect of control on penicillium mycotoxins during storage in apple, pear and citrus, sodium hypochloride gas and heat at $37^{\circ}C$ treatment exhibited effective control. Especially, heat at $37^{\circ}C$ treatment exhibited 100% effective control without any injuring by treatment. In pear and citrus sodium hypochloride gas treatment caused injury by treatment.

• Korean journal of applied entomology
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• v.17 no.1 s.34
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• pp.7-13
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• 1978

Experiments were conducted to study the integrated control of one of the major pests of citrus, the citrus red mite, Panonychus citri (McGregor). Studies were conducted in Seogwipo, Cheju Island, 1973-1976. Results obtained were: 1. The major peak of citrus red mite occurrence was mid-July to mid-August. 2. Standard field populations of citrus red mite were also high in September, October, and November. 3. A total of 10 species of natural enemies of citrus red mite were found. These included; Oligota yasumatusi Kistner, Anystis baccarum L., Hemerobiid sp., Semidalis albate E., Orius sp., Agistemus terminalis Q., 3 species of lady beetles (Coccinellidae), and one unidentified species of predacious mite. 4. Annual occurrence of citrus med mite tended to decrease in unsprayed fields, but increased in fields receiving standard treatments. 5. With fungicides, there was an increase in mite populations associated with use of Bordeaux mixture and copperpowder sprays. Streptomycin, however, did not effect on increase in mite numbers.