• Korean journal of applied entomology
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• v.33 no.2
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• pp.66-73
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• 1994

Adult emergence period, the calling behavior pattern and the mating ability of female depending on ages, 9day old male's response to sex pheromone released from each 1- to 5-day old female, and the structure and location of sex pheromone gland were obse~edin Ostrinia furnacalis. Adults usually emerged from 1 hour before to 1-2 hours after the beg~nning of scatophase under the 16L/8D photoperiod. And most active calling behavior was obserued for two hours from the 5th to 7th hours of scotophase among 2- and 3-day old females, and 3-day old male' response to 3-day old females was higher than to any other age of females during the 5th-8th hours of scotophase. Mating frequency was higher at the 4th-7th hours after the beginning of scotophase. Among 1. to Cday old females extruding sex pheromone gland, more than 65% of them successfully mated with 2- to 4-day old males. And, 2- or 3-day old females exhuding sex pheromone gland showed an abdiw. over 60%, to mate with each 1--5-day old males. Hypertrophied cell layers, presumed to be a sex pheromone gland of female adults, were located at two intersegmental membranes between the 8th & 9th, and the 9th & 10th abdominal segments.

• Korean Journal of Agricultural Science
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• v.45 no.2
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• pp.185-196
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• 2018

The fungus gnat, Bradysia difformis, damages various crops in greenhouses and is recognized as an important pest around the world. Additionally, in the future, many other greenhouse crops will be added to the list of crops damaged by the fungus gnat. In this study, to find effective control methods for the fungus gnat, the insecticidal effect of 20 chemical synthetic insecticides was tested with the potato disc and pot treatment methods; additionally, the control effect of 16 strains of B. thuringiensis was examined with the potato disk method. The fungus gnat larvae were treated for 2 days with each of the synthetic insecticides to determine insecticidal effect using the potato disc method. The results were as follows. Among the highly insecticidal active pesticides, chlorfenapyr exhibited a 100% insecticidal activity, and fenazaquin, acetamiprid, dinotefuran, fenthion and thiamethoxam exhibited more than a 90% insecticidal activity. For the pot treatment method, chlorfenapyr exhibited a 3.3% insecticidal effect, and thiamethoxam, acetamiprid, dinotefuran, fenthion, etc. exhibited an insecticidal effect of less than 10% of the emergence rate to adult fungus gnat after 14 days of treatment. To select the B. thuringiensis strains that have an insecticidal effect on the fungus gnat, 16 strains were biologically assayed using the potato disc method. Among the 16 strains, Bt-3, Bt-8 and Bt-13 had more than a 70% insecticidal effect. The $LC_{50}$ and $LC_{95}$ values of Bt-3, Bt-8 and Bt-13 were $3.7{\times}10^5$ and $4.7{\times}10^8cfu/ml$, $1.4{\times}10^5$ and $1.1{\times}10^7cfu/ml$, and $1.4{\times}10^5$ and $1.3{\times}10^7cfu/ml$, respectively.

• Korean journal of applied entomology
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• v.53 no.3
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• pp.287-293
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• 2014

Matsumuraeses phaseoli is one of the main pests that attack the flowers and pods of red bean (Vigna angularis) and mungbean (Vigna radiata) in Korea. To elucidate the developmental characteristics and over-wintering stage of M. phaseoli, several stages of the insect were observed through artificial rearing under outdoor conditions in Suwon ($37^{\circ}$16'N $126^{\circ}$59'E 35ASL), Korea. In colonies in which neonate larvae were reared at about 2-week intervals for more than a year, the developmental period from larva to adult emergence became longer from spring to summer, but shorter from summer to autumn; aestivation was not observed during the summer season. The colony in which rearing started on Oct 8, 2008 over-wintered as pupae and emerged in late April next year with a survival rate of 6%. However, the colony in which the rearing started on Oct 23, 2008 over-wintered as mature larvae, pupated in late April, and emerged in early and mid-May with a survival rate of 2%. When the fifth instar larvae were transferred outside from the laboratory ($25^{\circ}C$, 15L:9D) between November and February, no larvae could survive during the winter season. Some newly laid eggs and newly emerged adults could not hatch and could not survive, respectively, in outdoor conditions in November and December. These results suggest that neonate larvae of M. phaseoli that hatch in October can over-winter as late larvae or pupae in Suwon, Korea.

• Korean journal of applied entomology
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• v.44 no.4 s.141
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• pp.257-264
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• 2005

In order to establish the successive rearing system brush-footed butterflies (Lepidoptera : Nymphalidae) were reared in a room. Artificial diets were developed for a year-round rearing. Bu-diet was best to rear these butterflies among 3 kinds of diet used. The freeze-dried host plant leaf powder in diet was better than heat-dried one $(60^{\circ}C)$ in the growth of larvae. The rearing results were best in the diet C/N ratio was 1:1. The 24-hrs old eggs could be stored for 5 days at $15^{\circ}C$ or for 3 days at $5^{\circ}C$ and showed 75% of hatchability. On the other hand, pupae could be stored for maximum 15 days at $15^{\circ}C$ because the emergence of abnormal adults appeared much more as the cold storage period got longer. And the adult was able to be stored until 60 days at refrigerator without relation of nectar-sucking period before cold-storage and storage temperature. Also a simple artificial ovipositing kit was devised by ${\Phi}9$ cm of petri-dish and a female oviposited $278{\pm}27$ of eggs with adding the ether extract of host plant to this kit. The systematic successive rearing method of brush-footed butterflies in a room was completed.

• Korean journal of applied entomology
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• v.49 no.4
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• pp.343-349
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• 2010

The golden apple snail was introduced to the Korea from Japan as a potential food for people in 1983. It is one of the pests of direct-seeded rice in korea. This study was conducted to investigate rice(Oriza sativa) consumption and the extent of damage by the golden apple snail(Pomacea canaliculata) in direct-sown paddy fields. Food consumption of the golden apple snail was highest at $30^{\circ}C$. When the emergence of the 1st, 3rd, and 5th leave of rice supplied food, the consumption of young(shell height 15mm) and adult golden apple snail(over shell height 30mm) at $30^{\circ}C$ were 19.0/79.8, 11.0/54.5, 5.5/18.5, and 0.0/2.0 individuals, respectively. Young rice seedings(before 5th leaves of rice) are very susceptible to golden apple snail damage because the young, tender leaves and stems favor the snail's feeding habits. The field experiment with four treatments (0, 2, 5 and 10 individuals respectively per 10 $m^2$) was carried out. The most serious yield loss was 16% from the plot with 10 adults released at emergency stage of rice.

• Korean journal of applied entomology
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• v.37 no.2
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• pp.137-142
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• 1998

The regional distribution and some ecological characteristics of Chinese white-wax scale, Ericerus pela Chavannes, were investigated from 1996 to 1997. It was found that 10.8% of the stems of the privet, Ligustrum obtusifolium infested with the scale in Chtingpyijng, whereas only 1.1% of them infested in Y6ngwol and Pyongtaek. The average survival rate of the female adult marked 85.3% after it hibernated on the privet, Ligustrum obtusifolium. A female laid 7,783.5 eggs in average and 36.7% of females fell on the range of 7,000-10,000 eggs. It sized 0.40 mm in length and 0.21 mm in width. The hatchability was highest at 27$^{\circ}$C with 66.8% and it seemed the optimum temperature for incubation. The pupation rate was lower than 50.0% at the above experimental temperatures and the emergence rate marked 67.3% at 25$^{\circ}$C. When the egg was preserved at the various low temperatures, it was found that the egg could be preserved at lS$^{\circ}$C for 50 days in maximum.

• Korean journal of applied entomology
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• v.23 no.2 s.59
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• pp.109-115
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• 1984

This study was conducted to investigate the bionomics, host range and damage aspect of Japanese juniperus bark borer, Semanotus bifasciatus M., which shoves the severe damage for the Juniperace in Chonnam province, recently. Host plants were Juniperus virginiana, J. chinensis var. kaizuka, J. chinensis, Biata orientalis var. nepalensis, Chamaccyparis ostus and Thujopsis dolabrata. Out of those, J. chinensis var. kaizuka is newly investigated in this study. Damage rate in each area was $16.5\%$ in Kwangju, $4.25\%$ in Damyang ana $6.5\%$ in Hwasoon. Adults appear once a year, with a peak at late March to early April. Adults emergence during the day showed the peak at 13 to 15 hours and were influenced in the maximum temperature in a day. Attack direction of larva after invasion in the stem was $62\%$ toward base, $22\%$ toward tip and $16\%$ toward horizon, and the damage in each DBH (Diameter of breast height) was the greatest at $30\~40mm$. At period of each stage, egg was $15.8\~19.7$ days, larva was $l12\~126$ days and pupa was $15\~21$ days. Longevity of adult was 19 days for female and 16 days for male.

• Korean journal of applied entomology
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• v.50 no.1
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• pp.47-53
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• 2011

The seasonal occurrence of Riptortus pedestris Fabricius was investigated using pheromone traps baited with its aggregation pheromone in the fields with various crop composition (mixture culture of barley and hairy vetch in Asan, Chungnam; monoculture of hairy vetch in Yuseung, Daejeon) from mid-May to mid-July of seed gathering season in 2010. The invasion of R. pedestris into the experimental fields began to increase rapidly from late-June in which period hairy vetch and barley reach the beginning of seed formation stage. After seed gathering season in mid-July, the invasion rate of R. pedestris decreased, and the activity was continually observed till early-November. In addition to dominant R. pedestris species, 33 species of hemiptera including Apolyaus watajii, Dolycoris baccarum, Adelphocoris suturalis, and Yemma exlis were collected, which indicated abundant species diversity in the hairy vetch fields. In the laboratory, R. pedestris did not developed successfully to adult stage on food sources of hairy vetch, with decreasing survival rate after 4th instar and the failure of emergence to adult stage. Also, R. pedestris showed higher preference on soybeans than hairy vetch. Consequently, hairy vetch may be not true host for the development and survival of R. pedestris. It is considered that R. pedestris is a temporary visitor at the season of seed formation in hairy vetch fields.

• Tuberculosis and Respiratory Diseases
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• v.47 no.2
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• pp.184-194
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• 1999

Backgrounds : The advent of penicillin has led to the marked reduction in the mortality from pneumococcal bacteremia, however, the mortality is still relatively high in this post-antibiotic era. Actually the prevalence of infection due to penicillin-resistant penumococci is increasing worldwide, and it is especially high in Korea due to irrelevant use of antibiotics. So, the high mortality of pneumococcal sepsis might be related to the emergence of penicillin-resistant strains, however, many other antibiotics, which eradicate pneumococci effectively, are available in these days. This has led us to suspect the role of penicillin-resistance in the high mortality rate. In this study, we evaluated the effect of penicillin resistance on the mortality of patients with penumococcal bacte remia. Methods: The study population consisted of 50 adult patients with penumococcal bacteremia who were admitted between Jan, 1990 and July, 1997. Medical records were analyzed retrospectively. Results: Most of the patients (96%) had underlying diseases. The most common local disease associated with pneumococcal bacteremia was pneumonia (42%), which was followed by spontaneous bacterial peritonitis (14%), cholangitis (10%), meningitis (8%), liver abscess (4%), pharyngotonsillitis (4%), sinusitis (2%) and cellulitis (2%). While the overall case-fatality rate in this study was 24%, it was higher when peumococcal bacteremia was associated with pneumonia (42%) or meningitis (50%). The rate of penicillin resistance was 40%, which was increased rapidly from 1991. The rate of penicillin resistance was significantly higher in patients with the history of recent antibiotics use and hospitalization within 3 months respectively. The clinical manifestations, that is, age, severity of underlying diseases, nosocomial infection, associated local diseases, and the presence of shock or acute renal failure were not statistically different between the patients with penicillin-resistant and -sensitive pneumococcal bacteremia. The mortality of patients infected with penicillin-resistant pneumococci was not statistically different from those with penicillin-sensitive pneumococcal bacteremia. Conclusion: Penicillin resistance is not associated with high mortality in adult patients with pneumococcal bacteremia. As the overall mortality is high, active penumococcal vaccination is recommended in patients with high risk of infection.

• Korean journal of applied entomology
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• v.55 no.4
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• pp.421-429
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• 2016

Tenebrio molitor larvae contain large amounts of proteins, lipids and other functional materials, enabling this insect to be used as an edible food source in animal feeds and for industrialization. Although many efforts have been made to set up mass rearing systems, few studies have been conducted to establish optimal rearing conditions for the production of high quality T. molitor larvae. Herein we investigated 1) the effects of additional diets on the survival and fecundity of the insect, 2) the relationship between oviposition period and the uniformity of larval size, 3) the effects of rearing density and temperature on insect development, and 4) the storage stability of eggs and pupae at low temperatures given possible temporary production discontinuation. The addition of carrot and zucchini to the traditional wheat bran diet significantly increased the survival and fecundity rate of adult T. molitor. Of the three different oviposition sampling periods (3, 7, and 14 days) used to investigate the uniformity of the hatched larvae in each treatment, the period of 3 and 7 days provided higher uniformity than the 14 days oviposition period. Larval development was faster at $30^{\circ}C$ than at 20, 25, and $35^{\circ}C$. Interestingly, oviposition rates were highest at $20^{\circ}C$ but showed much slower larval development and lower uniformity at $30^{\circ}C$. Regarding the effect of larval rearing densities (1, 10, 20, 30, 40, and 50 larvae per 90 mm diam. dish), larval weight was significantly reduced at higher rearing densities, but larval longevity and length were not influenced by rearing density. The 30 larvae/dish is suggested to be a reasonable density to be applied to mass production systems. When kept at $4^{\circ}C$, T. molitor eggs showed a significant reduction in hatching rate; however, when stored under the same conditions, pupae emergence rates remained high until 10 weeks, suggesting that storage at low temperatures is more suitable for the pupal stage than the egg stage. Our findings suggest that an increase in T. molitor adult survival and fecundity rates and a uniformity of hatched larval development can be achieved with the following recommendations: a combination diet (including wheat bran), a 7-day oviposition period; a larvae-rearing temperature of $30^{\circ}C$, a rearing density of 30 larvae/dish, and the storage of pupal stages at low temperatures in the case of rearing discontinuation. This study serves as a strong foundation for the successful mass production of high quality T. molitor larvae.