• Journal of Forest and Environmental Science
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• 제36권4호
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• pp.290-297
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• 2020

This study analyzed and compared the damage rate, natural parasitic rate, and the morphological characteristics of Thecodiplosis japonensis larvae, which inhabit forest areas as control areas to large urban areas in 2018 and 2019. This research was conducted to provide basic data for the management of Thecodiplosis japonensis, which harm pine needles, and the results were as follows. First, the gall formation rate of Thecodiplosis japonensis collected from urban areas was upper-crown 35.59% and 34.25%, mid-crown 25.57% and 27.95%, and lower-crown 25.34% and 26.61%; the gall formation rate of Thecodiplosis japonensis was in the order of upper-crown>mid-crown>lower-crown in 2018 and 2019, respectively. In the control areas, the gall formation rates of Thecodiplosis japonensis in mountain villages in 2018 and 2019 were upper-crown 17.72% and 21.78%, mid-crown 13.85% and 16.97%, and lower-crown 15.12% and 15.79%; thus, in the order of upper-crown>lower-crown>mid-crown. The number of larvae in the galls of needles damaged by Thecodiplosis japonensis was as follows: the average number of larvae in the pine trees of urban areas was 9 and 8 in the upper-crown, 7 and 8 in the mid-crown, and 6 and 7 in the lower-crown respectively. This shows that the number of larvae was fewer in the lower-crown than the upper-crown, and that the number of larvae was higher in 2018 than in 2019. For natural parasitic rate of Thecodiplosis japonensis, the gall formation rate and natural parasitic rate of Thecodiplosis japonensis were surveyed; the natural parasitic rate was 12.5% and 11.8% in urban areas while the rate was 21.7% and 20.9% in mountain villages in respectively in 2018 and 2019.

• 한국연초학회지
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• 제13권1호
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• pp.36-42
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• 1991

The present study was conducted to obtain some basic information on the shoot formation from crown gall callus and the characteristics of teratoma shoot derived from crown gall induced by inoculation of Agrobacterium tumefaciens C58. Crown gall callus could be continuously cultured on the phyohormone free basic medium. The growth of crown gall callus was inhibited when BA were added to the cultural media. Shoot formation from crown gall callus fail to be initiated except teratoma shoot which induced on the phytohormone free medium after several subculture on rare occasions. Teratoma shoot could not form root and grow as normal shoot. Addition of BA to cultural media was not effective for shoot elongation, reduction in multiple shoot formation, but IBA was somewhat effective for shoot elongation of teratoma shoot, never for root formation.

• The Plant Pathology Journal
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• 제39권2호
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• pp.220-227
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• 2023

Rose crown gall caused by Agrobacterium tumefaciens is a major disease that damages the production of cutroses in Korea. The effective prevention methods for this disease include the use of resistant varieties. This study was conducted to evaluate the resistance of 58 Korean cultivars and six foreign cultivars to crown gall disease with nodal explants in vitro. Among 180 A. tumefaciens strains, pathogenic strain RC12 was selected as an inoculant strain. The strain RC12 was identified based on characteristics of some selective media, pathogenicity test, and polymerase chain reaction analysis. Forty rose cultivars formed tumors on explants inoculated with A. tumefaciens RC12. However, 24 cultivars, including 22 Korean cultivars and 2 foreign cultivars, showed resistance to A. tumefaciens RC12 without forming any tumors. Six cultivars with tumor formation rates of over 30% formed initial tumors within 23 days after inoculation. Six cultivars with low tumor formation rates of around 5% formed initial tumors after 28 days of inoculation. It was found that gall formation rate was highly correlated with the initial gall formation period. Thus, the relationship between the period of gall formation and the rate of gall formation could be useful for assessing resistance to crown gall disease. In vitro inoculation methods could be used to evaluate resistance of cut-rose cultivars to crown gall diseases.

• Journal of Ecology and Environment
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• 제35권3호
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• pp.177-188
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• 2012

We analyzed crown development in Aucuba japonica Thunb. var. japonica resulting from the responses of phytoelements to habitat light conditions over a long period of time. Over the years, the degree of extension unit (EU) dimorphism and the degree of anisophylly were higher under shaded conditions than in brighter conditions. An overall temporally increasing pattern in the degree of EU dimorphism was found while no clear-cut trend was found in the case of anisophylly. EU length and number of leaves per EU co-varied in a spatio-temporal context. The number of terminal buds and their sizes acted as the key initiators of morphological differences of phytoelements which were further amplified following bud break. Leaf area density was displayed mostly in the apex peripheral layer of the crown and the apex layer received most of the incident light. There was a tradeoff between annual leaf production and mean leaf size. Depending on the heterogeneity of irradiance level within a crown, correlative growth inhibition caused higher EU mortality at brighter sites. Due to high mortality, shorter EUs had a mere role in the construction of structural framework of the crown except for the formation of some gaps. There was a strong convergence of EU dimorphism, anisophylly, EU extension growth and variations in leaf size towards formation of functional crown to reduce potential self-shading. Depending on the irradiance level, Aucuba japonica Thunb. var. japonica showed two different modes of crown expansion. At the brighter sites, individual crown expansion was progressive while at the darker sites, individual crown expanded in a diminishing manner and maintained a stable size. A plant's "growth diminishing phase" appeared earlier at shaded sites than brighter sites.

• Bulletin of the Korean Chemical Society
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• 제12권4호
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• pp.368-370
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• 1991

The electrochemical behavior and the complex formation between N$i^{2+}$ and 1,7-diazs-15-crown-5 and 1,10-diaza-18-crown-6 in acetonitrile solution have been studied by DC polarography, differential puke polarography and cyclic voltammetry. Nickel(Ⅱ) complexes gave a single well-defined wave. The formation constants of their complexes were 1$0^{4.89} and 10^{3.86}$, respectively. Nickel(Ⅱ) ion was found to form complexes of 1-to-1 composition with 1,7-diaza-15-crown-5 and 1,10-diaza-18-crown-6. In addition, reduction steps were irreversible and the reduction current were diffusion controlled. The electrochemical reduction mechanism of Ni(Ⅱ)-macrocyclic diaza-crown complexes in acetonitrile solution is estimated.

• 대한화학회지
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• 제32권1호
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• pp.53-59
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• 1988

파라치환된 포타슘 페녹사이드류와 18-crown-6가 이루는 1 : 1 착물 형성상수를 전기 전도도법으로 35${\circ}C$에서 측정하여 용매와 치환기의 변화에 따른 효과를 측정하였다. 18-crown-6와 $K^+$의 착물 형성상수는 $CH_3$OH(DN=19.0) > DMF(26.6) > DMSO(29.8)의 순으로 감소되었다. 이는 전자주게 수가 클수록 $K^+$과 용매와의 상호작용이 커지므로 크라운 에테르와의 착물형성과의 서로 경쟁관계가 되어 $K_f$값이 작아진다고 추정된다. 포타슘 페녹사이드의 치환기가 p-N$O_2$ > H > p-$CH_3$ > p-O$CH_3$의 순으로 $K_f$값이 감소하는 경향을 나타내었다. 이는 전자를 당기는 기는 페녹사이드 음이온이 비편재화되어 안정해지므로 전자를 미는 기에 비해서 $K^+$를 쉽게 내어 놓을 수 있어 18-crown-6와의 착물 형성이 용이하기 때문이라고 생각된다.

• Journal of Ginseng Research
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• 제10권1호
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• pp.45-54
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• 1986

인삼에 이용할 수 있는 vector system의 개발연구의 일환으로 우선 Agrobacterium spp.를 인삼의 잎, 줄기 및 뿌리에 접종하여 crown gall tumor의 형성 및 탈분화 그리고 Agrobacterium spp.의 opine화합물의 이용정도등을 조사하였던 바 그 결과를 요약하면 다음과 같다. 1. Agrobacterium tumefaciens C58은 인삼의 모든 부위에서 crown gall tumor를 형성하였으나 secondary tumor나 teratoma는 형성하지 못했다. 2. Wild type Agrobacterium tumefaciens Y101, Y104, Y109는 crown gall tumor를 형성하였으며, tumor의 형태, 크기 그리고 생장 정도는 strain별로 차이가 있었다. 3. Agrobacterium tumefaciens Y194는 특히 amorphic tumor를 형성하였다. 4. 줄기에서 형성된 tumor조직에서 callus를 유기하고자 phytohormone free배지 및 2,4-D 첨가 배지에 접종한 결과 전혀 callus가 형성되지 않았다. 5. 뿌리에서 형성된 callus가 형성되긴 하였으나 출현빈도가 극히 낮았으며, 정상 조직과는 달리 2,4-D의 효과가 미미하였다. 6. Agrobacterium spp.에 의한 opone화합물의 이용능력을 조사한 결과, Agrobacterium tumefacciens Y104, Y110 과 C58은 nopaline type이었고 Y109는 octopine type이었으며, Y101은 nopaline과 octopine 어느것도 이용하지 못하였다.

• The Korean Journal of Ecology
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• 제8권4호
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• pp.197-200
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• 1985

The relations of crown width and DBH for Pinus densiflora, Pinus rigida, Pinus koraiensis, and Ginkgo biloba were accomplished to estimate the level of crown competition. Measurements of the relations revealed that crown width and DBH were highly correlated for the same species. Also it seems that these relations are independent of age and site quality. The results of regression analysis were as follow: P. densiflora, Y=0.3477X+0.3828 r=0.95 p. rigida, Y=0.3537X+0.1645 r=0.95 P. koraiensis, Y=0.2895X+0.6310 r=0.92 G. biloba, Y=0.4360X+0.0995 r=0.90 The significant differences between G. biloba and pine species seems due to their structural differences of crown formation according to tree species. As results of computing Maximum Crown Area and Crown Competition Factor as indices of crown competition, they indicated that P. densiflora would grow better under the natural conditions.

• Bulletin of the Korean Chemical Society
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• 제27권6호
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• pp.886-892
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• 2006

The interaction between tetraethylammonium chloride (TEACl) with ICl and tetraethylammonium iodide (TEAI) and aza-15-crown-5 (A15C5) with $I_2$ and ICl have been examined spectrophotometrically in acetonitrile solution. The results of TEACl-ICl indicate the formation of $ICl_2$ - through equilibrium reaction. In the case of TEAI-$I_2$ and A15C5-$I_2$, the equilibrium formation of $I_3$ - is confirmed. The interaction of TEAI-ICl begins with the simultaneous production of $I_2$ and IC$I_2$ - (at TEAI/ICl < 0.5) as well as continues with the simultaneous consumption of $I_2$ and formation of I$I_3$ - (at TEAI/ICl > 0.5). Similar behavior is also observed for A15C5-ICl system. However, the changes are seen at A15C5/ICl mole ratios less and more than 0.66. Several equations have been suggested for the formation of detected species. The formation constants of various reactions were evaluated from the computer fitting of the absorbance-mole ratio data. IR spectra of A15C5 and 1:1 A15C5:ICl or A15C5:$I_2$ complexes are compared and the effect of complexation on absorption bands is discussed.

• Bulletin of the Korean Chemical Society
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• 제11권6호
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• pp.521-527
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• 1990

The binding characteristics and analytical applications of anilinium ion complexes with 18-crown-6 were studied by polarography and NMR. First, the electrochemical reduction of the 10 species of mono and dimethylsubstituted anilinium ion complexes with 18-crown-6 as host in methanol are examined. The addition of 18-crown-6 to anilinium guest solution the polarographic waves remain well defined but shifted toward more negative potentials, indicating the complex formation. The values of formation constants, log Κ for 10 species of methylsubstituted anilinium ion complexes with 18-crown-6 varies from 2.7 to 4.8 in methanol at $25^{\circ}C$. The stability order of complexes for 18-crown-6 is anilinilum > 4-methyl > 3,4-dimethyl > 3-methyl > 3,5-dimethyl > 2,4-dimethyl > 2,5-dimethyl > 2,3-dimethyl > 2-methyl > 2,6-dimethylanilinium ion. The steric hindrance shows significant effect. Second, Proton NMR was used to elucidate their interaction characteristics. From the results of so called NMR titration techniques, the behaviors of binding sites on complexation, and the stoichiometry and stability order of complex were obtained. And the later results show the satisfactory agreement with the quantitative values obtained by polarography. Finally, the individual determinations of anilinium ion mixtures were also accomplished by addition of 18-crown-6. In some mixtures of methyl or dimethylanilinium ions the reduction peaks of differential pulse method appeared into one unresolved wave attributed to the small difference of half-wave potential, ${\Delta}E_{1/2}$. In the presence of 18-crown-6, the polarographic waves were resolved into individual maxima because of the shift toward more negative direction by the difference of selectivity of anilinium ions with 18-crown-6. It may be concluded that quantitative analysis of methylanilinium ion mixture make possible because the half-wave potential shift by the selectivity difference due to the steric hindrance between methyl group and 18-crown-6 on complexation.