• 한국연초학회지
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• 제11권1호
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• pp.3-9
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• 1989

Field experiment was conducted to find out the cause of calcium deficiency of burley tobacco (Nicotiana tabacum L.), Liming materials and application rate were CaSO4 : Ca 35kg/10a, CaCO3 : 35kg/10a and agricultural lime : Ca 142kg/10a. The breakdown in tissues at tips and margins of upper leaves was developed at maximum growth stage. If complete breakdown and death does not occur and growth takes place later, giving the leaf a scalloped appearance. Upper leaves contained lower calcium content than other leaves. The stem and midvein of calcium deficient plants contained lower calcium and calcium minus oxalic acid, but higher oxalic acid contents than those of normal plant. Fresh leaves of limed plot contained higher calcium and oxalic acid, but not significant increment of calcium minus oxalic acid than those of unlimed plot. Since calcium oxalate is insoluble, it could precipitate within the culls if the calcium and oxalic acid are accessible to each other. It suggest that high level of oxalic acid in stem and midvein could be interfering with translocation of calcium to upper leaves.

• 한국연초학회지
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• 제6권1호
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• pp.39-49
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• 1984

In the tobacco industry, it is important to study the change of mechanical property occurring the expansion process. The purpose of this study is to attain basic data for development of a tobacco expansion method. 1 . Freon gas was adsorbed to tobacco under various conditions of temperature, relative humidity and pressure, and then the amount of freon gas adsorbed was analyzed by GC. Freon adsorption rate of Burley 21 was more than that of By104 at the same condition and about 17 $\pm$ 1% moisture content produced better adsorption rate. 2. Freon adsorbed sample were heated to about $150^{circ}C\;to\;230^{\circ}C$ in a drying oven and recycle duct form about 2 to 30 seconds, and then the change of mechanical property were measured. Heated leaf was damaged when the tissue was pressed by the force of above $0.5x10^8dyn/cm^2$. The optimum condition of no damage of the sample was below the temperature of 15$0^{\circ}C$ and heating time of 10 seconds. It was more economically advantages to treated sample in a recycle duct than to be in a drying oven. By this process, the specific volume of the heated sample was increased from 80 to 110 percent in comparison to that of untreated sample.

• 한국연초학회지
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• 제4권2호
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• pp.3-10
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• 1982

This experiment was conducted to study the effect of soil water potenial on the growth and internal changes of stressed plants. The experimental imposition of soil water potential ( $\Psi$soil) were -0.1 to -0.2, -0.2 to -0.5, -0.5 to -3.0, -3.0 to -10.0 bar respectively. During water stress all growth rates were depressed, and the most sensitive period to water stress was found to be 10 to 25 days after transplanting. The water potential of leaf was declined rapidly within 12 hours after with holding of water. Nitrate reductase activity was decreased progressively as water deficit was built up in tobacco leaves, but the activity of alpha- amylase and super contents were increased. There were differences in peroxidase isozyme patterns between tile control and water stressed plant. New isozymes started to appear as tobacco leaf water potential decreased.

• 한국연초학회지
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• 제5권2호
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• pp.25-32
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• 1983

To obtain basic information on the breeding of burley tobacco, classification of 41 varieties was carried out by using the cluster analysis of correlation coefficients and taxonomic distance based on twenty-one agromonic characters. Eight characters, such as days to flowering, length of flower axis, internode length, leaf length, yield, leaf angle to stem, vein angle to midrib and plant height, were useful in monothetic classification. Forty-one varieties were classified into four groups (I, II, III and IV) with weighted variable group method (WVGM ) and weighted jai. group method(WPGM), whereas the results classification of 33 varieties among them by WVGM were coincident with the results by WPGM. As for the characteristics of each group, group I related to late maturity, tall height and high yield, group II related to intermediate maturity, tall height and low yield, group 19 related to early maturity, intermediate height and low yield, and group W related to early maturity, short height and intermediate yield.

• 한국연초학회지
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• 제7권1호
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• pp.33-38
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• 1985

In spite of their inferior quality, pale yellow flue-cured tobacco varieties (N. tabacum L.) are being cultivated as pre-crop of rice in paddy field because of its early leaf maturity. Fertile and male sterile Hicks as green variety , three pale yellow varieties and six single cross $F_1$ hybrids between green and pale yellow varieties, were evaluated. Fertile $F_1$ hybrids were similar to pale yellow varieties in early leaf maturity, curing characters and nicotine contents, where-as they were lower in total nitrogen, higher in reducing sugar comparing to those of the pale yellow varieties.

• 한국약용작물학회지
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• 제18권6호
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• pp.416-420
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• 2010

Root yield and quality of ginseng cultured in paddy soil was low relatively compared with that of upland soil because of moisture injury in root during rainy season. Drainage class in soils generally divided into 6 classes, and it is possible to cultivate ginseng practically in imperfectly drainage class (IDC). This study carried out to select the varieties that is suitable for paddy soil, which is easy to be generated rusty-colored root and physiological-discolored leaf. Experiment plot arranged with the condition of soil humidity contents such as poorly drainage class (PDC) and imperfectly drainage class (IDC), and upland soil. Growth characteristics and root yield were investigated in four-year-old ginseng of varieties, Cheonpoong (CP), Yeonpoong (YP), Hwangsookjong (HS), and Jakyeongjong (JK). CP among four varieties showed the highest yield in IDC and CP was the lowest ratio in leaf discoloration and rusty-colored root. HS was followed by CP in the order of root yield, but it had the weakness that the ratio of rusty-colored root was high respectively.

• Journal of Ginseng Research
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• 제4권1호
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• pp.16-30
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• 1980

In order to increase the production of ginseng, a cultural experiment was carried out under different types of natural forest condition. Seedlings were transplanted with three spacing (70,90 and plants per 1.62m2) under the broad leaved, needle and mixed forest. The obtained results are as follows. 1 Growth of aerial part of ginseng plant. 1) Vegetative growth under forest condition of very poor as compared with ordinary cultivation, but there was no significant in number of leaf and teasel. 2) Stem diameter and stem length under the different forest types were a little difference. However petiole length and number of leafet showed an increasing trend in broad leaved forest as compared with other forest types. 3) The withering date of aerial part of ginseng plant in the needle forest was later than of others. 2. Fresh weight of ginseng root per plant was decreasing in the order of broad leaved forest, needle and mixed forest, needle and sized forest respectively. However the root weight was much smaller than that of ordinary cultivated one. 3. No big difference was observed in the growth of both aerial and root among the planting density 4. Nitrogen content in ginseng root under forest was lower, but calcium content In root was higher than that of ordinary one. 5. Fat and fiber content of ginseng root under forest showed higher than that of ordinary one. 6. The saponin content of ginseng root grown under forest condition was higher than that of ordinary ginseng root. According to high performance liquid chromatogram of saponin, only difference from ordinary cultivated ginseng root was that ginsenoside Re showed higher peak than ginsenoside Rg1.

• 한국작물학회지
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• 제30권4호
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• pp.398-404
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• 1985

본 연구는 4년생 고려인삼의 재식위치에 따르는 잎의 형태적 특성과 광합성능력 및 암호흡의 계절적 변이를 구명하기 위하여 수행하였던 바 그 결과를 요약하면 다음과 같다. 1. 엽장, 엽폭, 엽중 및 엽면적지수는 후열에 비해 전열에서 현저한 증가를 보였고 또한 6월에 비해 9월에 증가된 경향이었으며 특히 후열엽의 충실도는 6월에 비해 9월에 뚜렷한 증가를 나타내었다. 2. 기공의 수 및 크기는 6월에 비해 9월에 현저한 증가를 보였다. 엽록소a는 6월에 비해 9월에 현저히 감소되었으나 엽록소b는 계절간의 차이가 없었으며 또한 엽록소a, b 모두 6월에는 전열에 비해 후열에서 현저히 많았으나 9월에는 전후열간 차이가 인정되지 않았다. 3. 광합성 최적광도의 추정치는 9월에 비해 6월에 높았고 또한 후열에 비해 전열 재식인삼이 높았으며 15~2$0^{\circ}C$에 비해 $25^{\circ}C$이상의 온도에서 현저히 낮았다. 광보상점은 온도가 높을수록 현저히 높아졌고 6월에 비해 9월에 현저히 높았다. 4. 최대광합성량은 6월에는 후열에 비해 전열에서 현저히 많았으나 9월에는 후열 재식인삼에서 오히려 현저한 증가를 보였고 6월에는 20~$25^{\circ}C$에서 그리고 9月에는 15~2$0^{\circ}C$에서 최대광합함량을 나타내었으며 그 이상의 온도에서는 현저한 광합성량의 감소를 나타내었다. 5. 광합성 최적온도는 6월은 21~$25^{\circ}C$였고 9월은 14~21$^{\circ}C$였으며 모두 전열에 비해 후열에서 현저히 높았다. 계절 및 재식위치에 관계없이 인삼엽의 암호흡은 온도상승에 따라 현저한 직선적인 증가를 보였고 Q$_{10}$은 6월의 전열에서는 1.7~2.1이었고 6월 후열 및 9월 전후열 잎은 1.3~l.8의 범위였다.

• 농약과학회지
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• 제19권1호
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• pp.14-21
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• 2015

인삼의 재배환경에 따른 잔류특성을 조사하고 살포 농약의 행적을 알아보기 위하여 5년근 인삼포에 덮개 유무와 인삼 줄기의 움직임으로 생긴 구멍을 흙으로 메우는 방법 여부의 서로 다른 조건에서 azoxystrobin (20% SC)을 안전사용기준의 기준량과 배량농도로 수확 7일전까지 10일 간격으로 4회 살포하였으며, 행적 구명 시험을 위해서는 기준량을 1회 살포한 후 분석시료를 채취하였다. 재배기간 중 덮개를 설치하고 구멍을 막은 경우가 잔류량이 낮아 덮개 설치와 구멍 메우기가 잔류량 감소에 기여하는 것으로 판단되었다. 인삼에 살포한 azoxystrobin은 비표면적이 큰 잎에 가장 많이 분포하였으며, 살포시기가 인삼의 수확기에 근접할수록 잎 중 잔류량은 감소하였으나 토양표면의 검출량은 증가하였다. 뇌두를 포함한 인삼 뿌리 중 시험농약의 분포율은 약 0.1%이었으며, 인삼 섭취 시 뇌두를 제거할 경우 12.7-20.4%(평균 16.6%)의 잔류농약 섭취를 감소시키는 효과가 있었다.

• 한국균학회지
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• 제49권4호
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• pp.555-560
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• 2021

During disease surveys conducted from 2019 to 2021 in Korea, leaf spot symptoms in rhubarb (Rheum rhabarbarum) plants were frequently observed in plants growing in fields located in Cheolwon, Taebaek, and Inje in Gangwon Province. The incidence of diseased leaves of the plants in the fields ranged from 2% to 80%. Nine single-spore isolates of Phoma sp. were obtained from lesions of the diseased leaves; all of them were identified as Didymella rhei based on their cultural, morphological, and molecular characteristics. Three isolates of D. rhei were tested for pathogenicity on rhubarb leaves using artificial inoculation. All the tested isolates caused leaf spot symptoms in the inoculated plants; the symptoms were similar to those observed in plants from the fields investigated. This is the first report of D. rhei causing leaf spot in rhubarb in Korea.