• Korean journal of applied entomology
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• v.14 no.1 s.22
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• pp.13-21
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• 1975

Experiments were conducted to select the new varieties and or/lines of rice resistant to the green rice leafhopper, Nephotettix cincticeps Uhler, and to evaluate the nature of their resistance to the insects in connection with the antibiosis and feeding and ovipositional preferences. The materials tested in this study were the varieties and or/lines of rice mostly proposed by the International Insect Resistance Nursery of IRRI and some others also orginiated from IRRI. Out of the 48 varieties and or/lines the 9 were selected as resistant and the 11 as mderately resistant. They have high antibiosis to the insects, showing significantly higher nymphal mortality and less adult emergence in the resistant and moderately resistant ones than the susceptible and moderately susceptible varieties Jinheung and Tong-il. Feeding perference was significantly different between the resistant and susceptible rice plants, resulting in much lower on resistant ones and much higher on susceptible ones. Ovipositional preference, however, was not different at all between the resistant and the susceptible ones. The nature of varietal resistance of rice to the green rice leafhopper seemed to be surely associated with the antibiosis and non-feeding preference.

• Korean Journal of Clinical Pharmacy
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• v.23 no.4
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• pp.307-315
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• 2013

Objective: Colistimethate was first became available in 1950s and used until the early 1980s to treat infections caused by gram-negative bacteria and was abandoned due to its nephrotoxicity and neurotoxicity. However, it was recently reintroduced into the clinical practices due to emergence of multidrug-resistance gram-negative bacteria, particularly Pseudomonas aeruginosa and Acinetobacter baumanii. Therefore, it is increasingly used in the intensive care unit settings as a salvage therapy. This study was designed to investigate the incidence rates and risk factors of acute kidney injury associated with colistimethate by using the standardized definition in critically ill patients. Methods: This study retrospectively reviewed the electronic medical records of 71 adult patients above 18 years old receiving intravenous colistimethate at least 48 hours at intensive care unit, university-affiliated hospital from Nov 2012 to Aug 2013 and excluded patients with end-stage renal disease (ESRD) and required renal replacement therapy before initiation of the colistimethate therapy. Acute kidney injury (AKI) was determined by using the standardized RIFLE criteria, classified with risk, injury, failure, loss and ESRD according to serum creatinine (Scr) levels. Results: Among the 71 patients included in the analysis, AKI developed in 40 patients (56.3%) and 6 patients (8.4%) had irreversible kidney injury. AKI occurred within 5 days in 20 patients (50.0%). Maximum Scr level showed a significant increase in the patients with AKI ($1.92{\pm}0.86mg/dL$ vs. $1.12{\pm}0.46mg/dL$ p=0.001), maximum BUN also increased ($64.2{\pm}28.7mg/dL$ vs. $48.4{\pm}24.9mg/dL$ p=0.017) and minimum creatinine clearance (CLcr) was significantly decreased in the patients with AKI than non-AKI ($34.5{\pm}18.6ml/min$ vs. $64.4{\pm}33.7ml/min$ p=0.185). The patients with AKI had significantly longer duration of colistimethate therapy ($21.1{\pm}17.0$ days vs. $13.0{\pm}11.5$ days, p=0.020) and larger cumulative doses of colistimethate ($6465.9{\pm}4717.0mg$ vs. $4438.1{\pm}3426.7mg$, p=0.040). Conclusion: The incidence and severity of AKI associated with colistimethate in critically ill patients was high and serious. Drug monitoring program should be performed to shorten duration of therapy and reduce cumulative dose from initiation of colistimethate therapy for minimizing AKI of colistimethate.

• The Korean Journal of Pesticide Science
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• v.13 no.1
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• pp.54-61
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• 2009

EPN-resistant diamondback moth were tested the developmental characteristics, longevity, fecundity and synergistic effect with synergists when treated with the bistrifluron, an inhibitor of chitin synthesis. Inhibition rate of egg hatch was below at the recommended concentration (50 ppm) to the EPN-resistant strain than EPN-non selected strain, however, mortality within 24hr after hatching was showed as 50-60%. They did not show the difference between two strains. Mortality of larval instars were showed effective to two strains with no difference. Inhibition rate of emergence did not show any effect when treated with pupae. Moreover, they did not affect to the longevity and fecundity. When bistrifluron was treated at 50 ppm to the adult, however, longevity and fecundity was decreased with no difference between two strains. Bistrifluron to the EPN-resistant strain showed synergistic effect as high as 137.7 and 73.1 folds with synergist such as PBO (microsomal oxidase inhibitor) and polyoxin B (chitin synthetase inhibitor), respectively.

• Korean journal of applied entomology
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• v.13 no.2 s.19
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• pp.77-82
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• 1974

The variety Tong-il from the IR667 lines have been reported as a variety resistant to the smaller brown planthopper, Laodelphax striatellus Fallen, in Korea. The resistance of Tong-il to the insect, however, have been mainly evaluated from a viewpoint of plant reaction of rice at the seedling stage. In this study, the nature of resistance of Tong-il to the insect was furthermore evaluated from the standpoints of feeding preference, antibiosis and plant tolerance in comparison with the resistant varieties Karsamba Red ASD-7 and Vellailangalayan. and the susceptible variety Jinheung which have been reported to the insect. The smaller brown planthopper much more prefered Tong-il for feeding than the resistant varieties ASD-7 and Vellailangalayan. The degree of antibiosis of Tong-il to the smaller brown planthopper was significantly lower than ASD-7 and Vellailangalayan. The results showed significantly lower nymphal mortality and higher adult emergence in Tong-il and Jinheung than other two resistant varieties. The degree o( tolerance of Tong-il to the insect was also lower than ASD-T and Vellailangalayan. Only. Tong-il seemed to be relatively more tolerable than Jinheung. The reason of showing resistant reaction of Tong-il in the mass screening test might be related with relatively lower feeding preference and more tolerance than Jinheung and other susceptible varieties.

• Korean journal of applied entomology
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• v.48 no.2
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• pp.179-188
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• 2009

Nymphal development of the B and Q biotypes of Bemisia tabaci was normal on all seven tomato varieties tested. However, their nymphal development was different on red pepper varieties. B biotype was not normally developed on nine red pepper varieties tested. On the contrary, Q biotype was normally developed, but its adult emergence rate was very low in Nokkwang variety than in other eight varieties. The EPG analysis of the feeding behavior of Bemisia tabaci showed that B and Q biotypes had different duration of phloem phases on red pepper. Q biotype showed longer phloem phases than B biotype. On Nokkwang variety, Q biotype had short phloem phases and did not prefer to feed on Nokkwang variety. Interestingly, Q biotype was found to have long duration of phloem phases on eight red pepper varieties, but B biotype did not prefer to feed on red pepper varieties. However, both biotypes did not show any difference in feeding time on tomato varieties.

• Korean journal of applied entomology
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• v.48 no.1
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• pp.101-108
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• 2009

For biological control of larva of Cnaphalocrocis medinalis and Naranga aenescens do considerable damage to crops by folding and scraping the leaf tissue of rice, a large number of Bacillus thuringiensis isolates have been obtained from soil samples in Korea and the pesticidal activity was assayed against two insect pest species described above. Among 53 Bt isolates tested in bioassay, 18 and 13 isolates showed over 90% mortality against C. medinalis and N. aenescens, respectively. Some isolates (11 isolates including CAB141) presented dual activity against C. medinalis and N. aenescens. These isolates showed over 96% control effect in pest control in laboratory against larvae of C. medinalis. Also, it was investigated that pupation, pupal length, and adult emergence of larvae exposed to Bt suspension decreased. Especially, the pupal length of C. medinalis after being fed corn seedling leaves treated Bt suspension for 10 days, were much smaller than that of control.

• Korean Journal of Ichthyology
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• v.29 no.1
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• pp.62-68
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• 2017

The Alaska pollock (Gadus chalcogrammus) belongs to the family Gadidae; it is a cold water fish, and has been developed as a novel aquaculture species in Korea. In this study, we describe ongoing surveillance for aquatic animal pathogens based on growth stages. We investigated bacterial flora in rearing water, and monitored pathogens; we also analyzed histopathological traits of abnormal fish. In rearing water, the total bacterial counts were $2.1{\times}10^3cfu/mL$ and Vibrio spp. (52%) were predominant in the larvae stage. In the juvenile and adult stages, the total bacterial counts were $3.4{\times}10^3$ and $3.2{\times}10^2cfu/mL$, respectively (with Pseudomonas sp. as the predominant species; 90% and 52%). This result revealed that the bacterial flora in rearing water changed depending on the feeding types. No virulent-bacteria or problematic viruses (VHSV, viral hemorrhagic septicemia virus; NNV, nervous necrosis virus; MBV, marine birnavirus) were detected from outwardly healthy fish using either culture or PCR assay. Some juveniles (less than 5%) had gas bubbles on the gill lamellae, degeneration of the corneal epithelium, and choroid gland degeneration, suggesting that these symptoms were caused by external injury and secondary infection by opportunistic bacteria. Disease management is important to cope with disease emergence in the novel aquaculture species Alaska pollock.

• Korean journal of applied entomology
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• v.34 no.3
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• pp.249-255
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• 1995

These experiments were conducted to investigate the life history and the seasonal fluctuation of population density of tea red spider mite, Tetranychus kanzawai Kishida and to observe its natural enemies in the southern area. Under field-cage conditions, tea red spider mite occurred 11~12 generations. The average periods from egg to adult emergence were 8.7~13.1 days in summer and 12.6~24.9 days in spring and autumn. The average longevities of adults were 15.5~21.9 days in summer and 25.1~31.6 days in spring and autumn. The average number of eggs laid per female were 45.1 in summer and 52.6 in spring and autumn. Tea red spider mite population showed two peaks during April-June, and appeared third or forth peak during October-November. The density of all the stages was the lowest in July through August. Tea red spider mites stayed at lower parts of tea plants in March but they moved to upper parts in April though June, and they again moved to lower parts after autumn. Tea red spider mite overwintered as all stages. Adults were the dominant overwintering stage during this stage. The surveyed natural enemies of the tea red spider mite were 7 species including Amblyseius longispinosus (Evans), A. eharai Amitei et Swirski, Anystis baccarun (L), Agistemus fleschneri Summers, Orius sauteri Poppius, Oligota yasumatsui Kistner and Scolothrips sp.

• Korean journal of applied entomology
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• v.17 no.3 s.36
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• pp.155-160
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• 1978

This experiment was carried out to develope a technique for labelling pine gall midge with ·radioactive phosphorus and calcium. This technique evolved would help to obtain basic information on the appropriate concentration of $^{32}P\; and\; ^{45}Ca$ in tagging and determination of adult flight ranges which considered as one of the factors in dissemination. 1. Labelling at the larval stage of pine gall midge by injection of $^{45}Ca$ into pine tree trunk appeared not to be effective for tagging the adults because radioactivity was gradually decreased to background by emergence. 2. The radioactivities of larvae in the galls gradually increased in September but from October 1 the activity was gradually decreased for 10 days then equilibrium was maintained thereafter. The results seem to indicate that larval diet termination occured early October. 3. A maximum level of radiation was detected at 3 weeks after $^{32}P$ injection and thereafter it was gradually reduced. This result implies that $^{32}P$ is not appropriate radioisotope in labelling pine gall midge through trunk injection method. 4. After washing in running water for 10 minutes, the optimum$^{32}P$ concentration for treated overwintered larvae and pupae was found to be 0.5 micro curie per ml. for 30 minutes dipping.

• Korean journal of applied entomology
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• v.52 no.3
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• pp.227-237
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• 2013

The black soldier fly (BSF), Hermetia illucens, is a generalist detritivore that is usually exploited for recycling environmental wastes, including food remnants. These insects can also be used to produce antibiotics for medical applications. For this purpose, flies need to be mass-reared using an automatic rearing system that generates various sounds. Insects use sound as a means of communication for mating or warning against predators. Thus, extrinsic sounds may interrupt the normal physiological processes of insects. In this study, we analyzed the physiological changes due to various sound treatments at $25^{\circ}C$ and 8:16 h (L:D) photoperiod. At 95 dB, larvae were exposed to different sound frequencies (0-5,000 Hz). The treated larvae were adversely affected by the high-frequency sounds and showed significant reduction in pupation and adult emergence. Different sound intensities (0-105 dB) at 5,000 Hz caused significant changes in the pupation and survival of the adults at 85 dB or above. Under a stress sound condition (5,000 Hz, 95 dB), the BSF larvae exhibited aberrations in the expression of genes related to the immune system and digestion. These results indicate that high-frequency sound treatments at or above 85 dB act as a stress sound to BSF development.