• Journal of Sericultural and Entomological Science
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• v.41 no.1
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• pp.36-40
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• 1999

The optimal condition for the production of the artificial fruiting bodies of Paecilomyces japonica in bulk was determined from the observation of the conidial, hyphal, and cultural condition and the medium. The colony was grown 32 mm diameter in 14 days on potato dextrose agar(PDA). Conidia was irregularly long oval-shaped and measured 4.07${\times}$1.56 ${\mu}$m in average. The hyaline hyphae formed transparent bundles which branched out. The fruiting body on the insect surface was measured 30 to 50 mm in length and formed up to 55 branches. Potato dextrose(PD) both was the most effective for the growth of Paecilomyces japonica among the liquid type media. About 3.1 mg mrcelia in dry weight were produced in 50 ml/PD broth. The best condition for the production of conidia under which condition 4.3${\times}$10$^8$ conidia/ml were harvested was pH 5.0 in acidity and 20$^{\circ}C$ following preculture at 24$^{\circ}C$ in temperature for 7 days.

• Journal of Sericultural and Entomological Science
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• v.41 no.2
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• pp.108-115
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• 1999

An improvement of methods in fibroin hydrolysates preparat significantly enlarges their applications to practical use. Acidic hydrolysis by hydrohloric acid is one of the methods for silk fibroin depolymeriza6tion. A low yield of final product and long time of the process are the demerits of this method. Possibility of preparation of water-soluble silk hydrolysates with more yield and less expenses is investigated in this study. Such possibility is occurred with the increasing tratment temperature and simultaneously decreasing treatment time, concentration of hydrochoric acid respectively, the concentration of sodium hydroxide used for neutraliza6tion of hydolysates after hydrolysis. Colour is decreased in this case and a small amount of activated, too. Protection of hydrolysates against precipitation after neutraliza6tion, and separation and during concentrating process is the other merit of this method. Creamy-coloured insoluble silk powder is the remainder of hydrolyzed fibroin. This is the only the immobiliza6tion of enzymes and other physiological active substances. Fine particles of this powder can be used as additives for artificial diets and cultural media, as well as raw materials for polymer membranes, etc.

• Korean journal of applied entomology
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• v.47 no.4
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• pp.479-486
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• 2008

The cultural characteristics and antibacterial activities of Cordyceps militaris and Paecilomyces tenuipes were compared. The mycelial growth was the highest on MCM (Mushroom Complete Medium) for C. militaris and on YMA (Yeast Malt Agar) for P. tenuipes. But the mycelial density on MMM (Mushroom Minimal Medium) was lower than other on media. The optimum mycelial growth was observed at $25^{\circ}C$. C. militaris was low mycelial growth when it was transferred over 5 times generation. The carbon source for the optimum mycelial growth was fructose of monosaccharide, maltose of disaccharide and dextrin of polysaccharide. The calcium nitrate of organonitrogen was found the best mycelial growth on C. militaris, while the sodium nitrate observed to be well for mycelial growth on P. tenuipes. The ammonium tartrate was observed to be the best among the inorganonitrogen used for mycelial growth. Antibacterial activities were found out just C. militaris against Bacillus cereus of Gram (+).

• Korean journal of applied entomology
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• v.24 no.1 s.62
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• pp.7-10
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• 1985

Transplanting date, planting space and nitrogen level were evaluated for disease development of rice sheath blight using two rice cultivars, Jinheung and Yushin. Sheath blight disease was more severe in early transplanting plot (May 16), narrow planting space($27{\times}12cm$) and high nitrogen level (220kg/ha for Jinheung and 300kg/ha for Yushin) conditions than in May 26 transplanting plot, wide planting space ($27{\times}15cm$) and standard nitrogen level (110kg/ha and l50kg/ha). At the same time, cultural conditions favorable for disease development during growth stage resulted in greater damage at maturing stage.

• Korean journal of applied entomology
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• v.19 no.2 s.43
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• pp.109-112
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• 1980

This study was carried out to investigate the distribution of egg parasitoids from green rice leafhopper, Nephotettix cincticeps Uhler, from the middle of August through the early September in southern rice cultural areas. The results were obtained as follow. 1. Four species of egg parasitoids, Gonatocerus sp. A and B, Paracentrobia andoi and Anagrus sp. are newly recorded from the eggs of green rice leafhopper. 2. Egg parasitism rates of Gonatocerus sp. were varied from $41.0\~73.9\%$ on an egg mass basis and from $29.7\~49.0\%$ on basis of egg. Percent parasitism rates by Paracentrobia andoi were $0\~9.7\%$ on an egg mass basis and from $2.1\~12.6\%$ on basis of egg. Gonatocerus sp. was dominant egg parasitoid in the parasitism rate than Paracentrobia andoi.

• Korean journal of applied entomology
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• v.23 no.2 s.59
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• pp.96-101
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• 1984

This experiment was carried out to investigate control efficacy by cultural practice and fumigation of tacterial wilt caused by Pseudomonas solancearum in resistant tobacco line NC82 at the Korea Ginseng and Tobacco Research Institute, Eumseong Experiment Station in 1982 and 1983. The bacterial wilt of tobacco occurred severely from mid-July to last August in applicable temperature and soil humidity for increasing bacteria. Disease severity appeared low and slowly at fumigation and resistant variety treatment. Incidence of bacterial wilt in tobacco line NC82 was $44.7\~55.8\%$ being compared with susceptible variety, NC2326 and $95\~99\%$ when resistant variety, NC32 was cultivated with soil fumigation treatment. Control efficacy of cultural practices appeared low with $0.8\~20\%$ and was not different from resistant variety and fumigation treatment. Control system against bacterial wilt in flue-cured tobacco was accomplished by control efficacy over $95\%$ when resistant variety(NC82) was cultured after treatment of cultural practices (Tillering after harvest and before transplanting, stalk and root destruction, early transplanting early removal of the mulching film) and soil fumigation(Cylon).

• Korean journal of applied entomology
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• v.59 no.1
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• pp.55-64
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• 2020

Smart greenhouses are primarily used for growing fruits and vegetables, such as sweet peppers, tomatoes, strawberries. Although the number of smart greenhouses has been increasing exponentially, no studies have been performed to evaluate the state of smart greenhouses in Korea. Therefore, this study was conducted to determine current state of smart greenhouses with regard to greenhouse specifications, crop growing methods, pests, and user satisfaction in Korea. Contact information for smart greenhouses was provided by the officials of local agricultural research and extension services. This survey was conducted by visiting each greenhouse. Results showed that approximately 50% of surveyed smart greenhouses were between 3,300 ㎡ and 6,600 ㎡. The most frequently chosen method for pest control was chemical pesticides (97.1%). Powdery mildew and gray mold comprised 54.4% and 33.8% of the crop diseases, respectively. All tomato greenhouse farmers considered whiteflies the most problematic pest. In contrast, 76.5% and 70.6% of sweet pepper farmers believed thrips and aphids posed significant threats, respectively. The mean satisfaction score was 7.5 out of 10 points, with 10 being "extremely satisfied". These results will aid in decision making with respect to the management of current smart greenhouses and the design of future smart farms in Korea.

• Korean journal of applied entomology
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• v.41 no.3
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• pp.177-181
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• 2002

This study investigated seasonal occurrence of Frankliniella occidentalis and its damage on chrysanthemum from 1999 to 2000. F. occidentalis adults were attracted to yellow sticky traps from early April to harvesting time in the field. The highest densities were observed from late April to mid-June in spring culture and from mid-August (just after transplanting) to early September in autumn culture respectively. Seasonal fluctuation in a PVC green house was similar to that in the field. Number of insects per flower were higher in the green house than that in the field. Leaf damages due to the insects were observed from mid-May and increased as chrysanthemum grows (R$^2$ = 0.9200-0.9887$\^$**/, p> 0.01).

• Korean journal of applied entomology
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• v.4
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• pp.1-6
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• 1965

In Korea the most important plant industry is the rice-growing but she has not yet attained self-sufficiency with regard to rice which is the basic food of Korean. In the past, various measures of increasing rice production have been tried with some success but the increasing rate of did not show the sufficient result. Judging from experiences, disease control may be the most important factor which has influence on increasing of rice production in Korea. During the past 60 years three periods divided by the transition of rice diseases were noted, and especially the recent transition attracted much attention . That is, sheath blight and stripe which were minor diseases in the past have promptly spread all over the country and caused heavy losses to rice plant, and also local outbreak of bacterial leaf blight and dwarf were noticed. Various environmental factors are related to such transition of rice disease. Above all, cultivated varieties susceptible to these diseases, increase of application of nitrogenous fertilizer, earlier transplanting and density of transplanting are considered to be lucre closely related to the development of these diseases and successive development of blast. On the other hand. application of forage fungicides such as organic mercury compounds specific to blast contributed to reduce prevalent area if blast in spite of wide spread of susceptible varieties and increase of application of nitrogenous fertilizer. These facts were confirmed by Korean investigators At the present which various diseases to control coexist in the same region, no one variety resistant to all of these diseases is provided and cultural practices for the control of these diseases often do not produce sufficient yield of rice. it is emphasized that a role of pesticides is very great.

• Korean journal of applied entomology
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• v.36 no.2
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• pp.141-144
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• 1997

Studies were conducted to investigate the incidense of insect pests in transplanted and direct seeded paddy fields in southern region of Korea. Population dencities of the rice green leafhopper (RGLH: Nephotettix cincticeps Uhler) and rice leaffolder (RLF: Cnaphalocroch medinalh Guenee) were higher in machine transplanted than in direct seeded, but the brown planthopper (BPH: Nilaparvata lugens Stal) and smaller brown planthopper (SBPH: Laodelphax striatellus Fallen) were abundant in direct seeded. However, no significant difference was found between machine transplanted and direct seeded fields in the incidense of rice stem borer (RSB: Chilo suppressalis Walker), whiteback planthopper (WBPH: Sogatella furcifera Horvath), and rice stem magot (RSM: C'hlorops oryzae Matsumura). Occurrence of rice key pests were affected more by transplanting time than other cultural practices. Later transplanting induced higher populations of BPH, WBPH, SBPH, RGLH. However, RSB and RLF caused higher damage in earlier transplanted paddy field.