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A Survey of the Aphids in Sulchon Area (I) (감자바이러스 매개진딧물 밀도조사(I))

  • Yoon Soon Ki;Choi Seong Sik
    • Korean journal of applied entomology
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    • v.9 no.1
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    • pp.43-48
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    • 1970
  • To investigate provincial seed Potato Production farms, a Preliminary survey on the local population of the aphids was made in Sulchon alphine area, Mooju-Goon, Chollapuk-Bo where the climatic conditions were almost same as those of Taegwanryong Kangwon-Do, where Alpine Experimental station is located. This area stands from 650 to 900 metres above the sea level and divided three location of A. B, C, by altitude. A stands at 900 metres above the sea level. B at 750 metres and C at 650 metres. A and B divided three points: Al, A2, A3, and Bl, B2, B3- and divided four points-Cl, C2, C3, C4- at the distance of 300 metres apart each other. The traps were operated from July 21 to October 31, 1969. Otherwise, the traps established at Suwon (inland) and Taegwanryong where Alpine Experimental Station. A total of some 70 species including five virus vector species were identified. The Numbers of species at 10 locations, Suwon and Taegwanryong are as follows; Al-34, A2-38, A3-29, B1-25, B2-26, B3-29, C1-27, C2-14, C3-32, C4-37, species (Table 1), Suwon-49 species (including 5 virus vectors species), Taegwanryong-22 species (including 4 virus vector species). The aphids are shown in Table 1 and the Vectors are as follows: 1. Aphis gossypii Glover 2. Aulacorthum solani (Kaltenbach) 3. Lipaphis erysimi (Kaltenbach) 4. Myzus persicae(Sulzer) 5. Phorodon humuli (Schrank) Numbers of vectors versus total aphid at each locations, including inland (Suwon) and alpine area (Taegwanryong) where Alpine Experimental Station are as Fig. 1. Of a total 8,902 aphids, 6,400 $(80\%)$ were Tetraneura sp. The number of aphids devoid of the number of Tetraneura sp. are as follows; (Numbers means mean of each locations) A; 215. B; 115, C; 176 and Suwon; 2,952, Taegwanryong; 247. Densities of aphids at the locations is lower :han those at Suwon and Taegwanryong. And density of vectors at the locations, at ranged from 11 to 37, is love. than those at inland (Suwon; 197) and alpine area (Taegwanryong; 90). Thus, this area is suitable for seed potato production as Multiplication field.

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Effect of light on conidial formation in several anthracnose fungi (몇가지 탄저병균의 분생포자형성에 미치는 광선의 영향)

  • Chung H. S.
    • Korean journal of applied entomology
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    • v.7
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    • pp.57-59
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    • 1969
  • Effect of light on conidial formation of Colletotrichum panacicola, C. gloeosporioides, C. runcatum and C. nicotianae was examined on potato dextrose agar on which each conidial suspension was seeded. The light source was Mitsubishi day light fluorescent lamps wi th an intensity of 100-120 ft-c at the colony surface. The treatments were (i)constant light, (ii) constant darkness, and (iii) alternating light (11hr.) and darkness {13hr.) at $26\{\circ}C\pm2$. With the exception of C. nicotianae, constant light gave the greatest sporulation over that obtained in the other two treatments; there were on significant differences in number of sporulation between under constant darkness and alternating light and darkness. C. nicotianae resulted in maximum. inter mediate and minimum sporulation under alternating light and darkness. constant darkness and constant light, respectively. These differences were statistically significant at $5\%$ level. C. truncatum and C. nicotianae produced abundant conidia in the entire test; C. gloeosporioides was intermediate, and C. panacicola was the least. Differences in number of sporulation due to light. organisms. and t he interaction of these two were all statistically significant.

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Studies on the Monoterpene Composition in the Oleoresin of Pinus thunbergii Parl. and the Resistance to Pine Gall Midge (해송의 Monoterpene 조성과 솔잎혹파리 내충성에 관한연구)

  • Kim, J.W.;Kim, C.S.;Ryu, J.B.;Kim, J.S.;Park, C.K.
    • Applied Biological Chemistry
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    • v.20 no.1
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    • pp.81-87
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    • 1977
  • Resistant and susceptible pine (Pinus thunbergii, Parl) trees to pine gall midge (Thecodiplosis japonensis, Uchida et Inouye) were selected and monoterpene composition in one year old branches, shoots and needles of both groups have been analysed by GLC. The results are summarized as follows; 1. Monoterpene composition in either one year old branches or shoots were not affected by their directions (North or South). 2. Major monoterpenes in one year old branches were ${\alpha}-pinene,\;{\beta}-pinene$, myrcene, limonene, ${\beta}-phellandrene$ and terpinolene. 3. In addition to ${\alpha}-pinene$, camphene, ${\beta}-pinene$, myrcene, ${\Delta}^3-carene$, limonene, ${\beta}-phellandrene$ and terpinolene, several less volatile components which appear to be monoterpenes were also present in shoots and needles. 4. Compared with the susceptible pine, the resistant tree was found richer in limonene composition. 5. ${\beta}-Pinene$ composition in the resistant pine was less than that in the susceptible pine. 6. The difference in the composition of limonene or ${\beta}-pinene$ between two groups of pine trees was discussed in relation to the resistance to pine gall midge.

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Floral morphology of the oak (1) (침나무류(類) 꽃의 형태(形態) (1))

  • Lee, Tchang Bok
    • Journal of Korean Society of Forest Science
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    • v.1 no.1
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    • pp.7-11
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    • 1962
  • 1. The inflorescence of the oak has been evolved through a serial reduction of the panicle as is presented in the figure 1. 2. Perianth lobes though they range from one to twelve in a flower six loves occur more than 50% of tested flowers as is tabulated in the table 1. They have been increased partly by a fusion of flowers and partly by a reversion of the stamen into the perianth lobe. They also have been decreased by a fusion of perianth lobes each other. 3. Stamen numbers in a flower range from one to twenty four, but eight stamens are more common than the others as is shown in the table 1. They have been increased by a fusion of flowers and decreased by a fusion of stamens in a flower as are presented in the figure 4. 4. Floral position in the inflorescence, environmental factors, hybridity, and abnormal nutrition supply seem to accelerate fusion and reduction of the stamen in a flower. 5. Flowers which consist of eight stamens and six perianth lobes occur more common than the others, however, the number of the stamen (Y) and the perianth lobes (X) appear to be correlated as follows (see also fig.5.). Y=1.09X+3.78, r=0.4 for Q. dentate Thumb. (7004 flowers investigated) Y=0.71X+4.18, r=0.48 for Q. mongolica Fischer (7409 flowers investigated) Y=1.03X+2.91, r=0.4 for Q. allena B1. (8662 flowers investigated) Y=0.69X+2.00, r=0.4 for Q. serrata Thumb. (9048 flowers investigated) 6. Morphological similarity of the bracteoles and perianth lobes as illustrated in the fig. 3, phenomena of a fusion of bracteoles and separation of perianth lobes into three groups in a flower, and increasing and decreasing phenomena of the stamen number and perianth lobes in a flower as presented in the figures 3 and 4 support the proposal on the oak flower evolution made by H. Hjelmquist in 1948.

Studies on the Collected Color Rice I. Botanical Characteristics for Color Rice Collected (유색미(有色米) 수집종(蒐集種)에 대한 특성(特性) 연구(硏究) I. 유색미(有色米) 수집종(蒐集種)에 대한 식물학적(植物學的) 특성(特性))

  • Choi, H.G.;Jung, J.Y.;Lee, H.B.;Jung, C.T.;Kim, B.K.
    • Korean Journal of Agricultural Science
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    • v.27 no.2
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    • pp.71-80
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    • 2000
  • This study was carried out to find the botanical characters for 27 color rice genetic resources collected from domestic 17 lines (including three varieties) and exotic 10 lines. We could gain the major informations from these materials for development of color rice variety. These lines showed a various variations in characters measured. Especially, Denorado introduced from Philippine was longer in culm length, panicle length and 1,000 grains weight than others. Whereas grain length and width of Sinucninul line introduced from Japan were similar to check, Heukjinjubyo. Heterosis degree for major characteristics of Suwon#432 ${\times}$ Heukmi#940018 combination among $F_1$ hybrids superior to others in tillers per plant, panicle length and 1,000 grains weight. Therefore, these lines and their combinations were expected as color rice developing line through progeny test in the future.

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Survey on the Spiders of the Rice Paddy Field ( I ) (논에 서식하는 거미의 조사(I))

  • Choi Seong Sik;Namkung Joon
    • Korean journal of applied entomology
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    • v.15 no.2 s.27
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    • pp.89-93
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    • 1976
  • The present report is dealt with the spiders which are caught within a space of $1m^2$ of rice paddy field where was harvested the rice crops in Jeonbug district, from November 4 to 11, to 1975. 1. Twenty-one species of spiders were caught at the area during the period. Of these the dominant species were Gnathonarium dentatum, Pirate subpiraticus, Gnathonarium gibberum, Oedothorax insecticeps etc. 2. Average density of spiders within a space of $1m^2$ of rice paddy field where rice crops was harvested was as follows: 125 at Iri, 102 at Jinan, 133 at Buan, and 58 at Daejang. 3. The scientific names of spiders which were caught in rice paddy field for the first time in Korea were Gnathonarium gibberum, Enoplognatha japonica, Erigone prominens, Erigonidium graminicola, Theridion octomaculatum, Lycosa pseudoannulata, Dolomedes angustivirgatus. As the result of this survey, fifty-five species of spiders were recorded in rice paddy field of Korea.

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Observations on the heating of grain caused by insects

  • Chyun Soon Pyo
    • Korean journal of applied entomology
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    • v.3
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    • pp.15-19
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    • 1964
  • 1. The heat output by the insects, Oryzaephilus surinamensis, Tribolium confusum, Sitophilus zeamais and Sitophilus granarius, was investigated by reading the temperature of the inside of the grain in which the insects were developing in 2 Ib or 7 Ib jars incubated at $25^{\circ}C\; and\; 70\%$ R.H. 2. All the insects tested increase the temperature of grain, but the amount of heat produced by insects varies with the species of and the developmental stages of the insects. 3. It was found that all the temperature peaks correspond with the peak in number of the fourth instar larvae and the period in which the insects start to cause the heating corresponds to its 1 st and 2nd instar larvae. 4. Sitophilus spp. whose larvae live in the endosperm of the wheat produced more heat than Tribolium confusum and Oryzaephilus surinamensis whose larvae live on the grain. 5. Among the four species of insects, Sitophilus zeamais Produces the highest heat, followed by Sitophilus granarius, Tribolium confusum and Oryzaephilus surinamensis. 6. It is considered from the above results that the heat produced by insects seems to depend upon the species, the number and the age structure of population, and its its surroundings. 7. It is suggested therefore that when comparing the rate of development of insects kept at different densities. the effects caused by heating at the higher densities must be considered.

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Some biological notes on Eriophyes kuko KISHIDA (1) Its biology and life history (구기자 혹응애(Eriophyes kuko KISHIDA)에 관한 생태학적 지견 (1) 그의 생태 및 생활사)

  • Kim C. H.
    • Korean journal of applied entomology
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    • v.5_6
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    • pp.59-63
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    • 1968
  • This Paper deals With the biology and the life Cycle of Eriophyes kuko KISHIDA. 1. The host of Eriophyes kuko KISHIDA is Lycium chinense MILL (Boxthorn), Solanum nigrum LINNE(Morel) and Capacium annum LINNE(Red pepper) etc. 2. Eriophyes kuko KISHIDA is migrated and propagated by physical carriers. The direction of the wind has a great influence upon migration and dispersal. 3. The number of e99s deposited by a adult female is $28.5\pm0.449$ egg period is $7.0\pm0.447$ and larval period is $4.33\pm0.667$ days respectively. 4. The size of gall diameter on the leaf of Lycium Chinense MILL after boring in each date by Eriophyes kuke KISHIDA is as follows, 1st day after boring is $290.5\pm0.3415\mu$ End 25st day after boring is $3260.5\pm0.5157\mu$ in average. 5. Adult periods are from 25 to 30 days and the egg laying period is 6 days. 6. Eriophyes kuko KISHIDA has 6 to 7 generations in a year, and hibernate they over winter in the gall as an adult. The first adult appears in late May.

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Morphological studies on the mouth parts of aphids and the penetration of stylets into their host plants (진딧물의 구기 및 기주식물에의 구침삽입 방법에 관한 형태학적 연구)

  • Kim S. P.
    • Korean journal of applied entomology
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    • v.5_6
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    • pp.9-18
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    • 1968
  • Morphological studios on the mouth parts of some aphids belonging to 5 sub-families and on the penetration of stylets into their host plants were carried out in order to find out possible relationship between mouth parts and capability of virus transmission. 1. There were no differences between the aphid species in general morphology of mouth parts. 2. Mouth parts could be observed in detail especially in Toxoptera citricidus and Chaitophorus chinensis. 3. Accessory salivary gland was larger than principal salivary gland in Toxoptera citricidus. 4. In 4 species, e. g. Chaitophorus chinensis, Myzus persicae, Aphis craccivora, Toxoptem citricidus, the stylets were usually inserted in plant tissues intercellularly and reached phloem, however, in Lachnus tropicalis only intracellularly and in Eriosoma clemalis more frequently intracellularly. 5. The stylets tracks of Eriosoma clemalis, Lachnus tropicalis and Myzus persicae were clearly visible but not in Toxoptera citricidus, Chaitophorus chinensis and Aphis craccivora. The tracks were stained with yellowish brown or red brown. 6. Saliva was seceted between the cell walls in most species and some substances in saliva seem to cause loosend cell walls. 7. The penetration of the stylets might cause physiological disturbance to host plants and could make the host plants susceptible to the plant diseases.

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Anti-Biofilm Effects of Torilis japonica Ethanol Extracts Against Staphylococcus aureus

  • Kim, Geun-Seop;Park, Chae-Rin;Kim, Ji-Eun;Kim, Hong-Kook;Kim, Byeong-Soo
    • Journal of Microbiology and Biotechnology
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    • v.32 no.2
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    • pp.220-227
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    • 2022
  • The spread of antibiotic-resistant strains of Staphylococcus aureus, a gram-positive opportunistic pathogen, has increased due to the frequent use of antibiotics. Inhibition of the quorum-sensing systems of biofilm-producing strains using plant extracts represents an efficient approach for controlling infections. Torilis japonica is a medicinal herb showing various bioactivities; however, no studies have reported the anti-biofilm effects of T. japonica extracts against drug-resistant S. aureus. In this study, we evaluated the inhibitory effects of T. japonica ethanol extract (TJE) on biofilm production in methicillin-sensitive S. aureus (MSSA) KCTC 1927, methicillin-resistant S. aureus (MRSA) KCCM 40510, and MRSA KCCM 40511. Biofilm assays showed that TJE could inhibit biofilm formation in all strains. Furthermore, the hemolysis of sheep blood was found to be reduced when the strains were treated with TJE. The mRNA expression of agrA, sarA, icaA, hla, and RNAIII was evaluated using reverse transcription-polymerase chain reaction to determine the effect of TJE on the regulation of genes encoding quorum sensing-related virulence factors in MSSA and MRSA. The expression of hla reduced in a concentration-dependent manner upon treatment with TJE. Moreover, the expression levels of other genes were significantly reduced compared to those in the control group. In conclusion, TJE can suppress biofilm formation and virulence factor-related gene expression in MSSA and MRSA strains. The extract may therefore be used to develop treatments for infections caused by antibiotic-resistant S. aureus.