• Korean journal of applied entomology
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• v.33 no.1
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• pp.6-11
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• 1994

The Spatial distribution pattems of the oriental tobacco budworm (OTB), Helicoverpa assuita, eggs w were studied in red pepper and tobacco fields. With a plant as a sample Unit. Taylor's power law analyses indicated that om egg spatial patterns were clumped in red pepper fields (a=1.3914, b = 1.1648) and were unifom in tobacco fields (a = 1.6035, b = 0.6880). In red peppers om eggs w were found in leaves (76.2%), fruits (16.8%), stems (6.5%), and flowers (0.4%). The upper leaf surface ( (70.1 %) contained sianificantly more eggs than the lower surface (25.2%). In tobaccos most eggs were also found in leaves. However, the lower surface (66.3%) contained significantly more eggs t th

• Journal of agricultural medicine and community health
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• v.26 no.2
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• pp.7-14
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• 2001

Cases of green tobacco sickness were described. During the cutting of tobacco plants throughout harvest, four cases of green tobacco sickness occurred in August 2001, Korea. The range of age was 42-55 years. The most frequent symptoms included dizziness, weakness, nausea, vomiting, abdominal cramps, headache, and difficulty breathing. All affected individuals worked in fields of wet tobacco, where their clothes became wet from moisture on the plants or sweating. They were all healthy, except one with hypertension. They are all non-smokers. They recovered after fluid and antiemetic administrations within two days. Most of doctors misdiagnosed their symptoms as a pesticide poisoning or heat injury. Green tobacco sickness is a condition that has long been known as an occupational health risk among tobacco harvesters. Nicotine poisoning by dermal absorption is reported to be the cause of green tobacco sickness. In Korea, there are many tobacco harvesters, and most of them may be sticken with green tobacco sickness. But, no case of green tobacco sickness has been reported. We report cases of green tobacco sickness occurred to the tobacco harvesters with a review of articles.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.15
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• pp.145-153
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• 1974

Five different levels of Ethephon were treated on tobacco cultivar yellow Special A and Coker and harvested for curing. Changes in dehydration properties, yellowing, chlorophyll, nicotine, sugar and starch contents during the processes of curing were studied in order to justify feasibility of adoption an idea of 3-stage-curing method instead of the 5-stage. Ethephon-treated-tobacco leaves showed marked degradation of chlorophyll, greater dehydration and greater reduction in nicotine contents while little change in either sugar, starch and other chemical components. They showed also shorter hours of curing period allowing possible curing response at a relatively low temperature than those without treatment. Thus they undergo only 3 stages of flue-curing processes, yellowing, calor-fixing and vein-drying, and need 72 hours to finish curing, but the ordinary leaves need 100 hours for it.

• Korean journal of applied entomology
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• v.28 no.2
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• pp.88-92
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• 1989

The Oriental tobacco budworm, Heliothis assulta (Guenee), larvae usually feed on the hot-pepper fruits and young tobacco leaves or buds in Korea. This experiment was conducted t(} compare their attraction to their host plants including fruits of the sweet-pepper and solanum uk kwang, besides the other two mentioned above. First instar larvae were most attracted to the hot-pepper fruits. Flowers or leaves of the hot pepper plants were not attractive either. When the hot-pepper fruits were compared for attractancy, based on developmental stages, relatively mature fruits, just before ripening, were the most attractive. Their extract with or without 10% ethanol also gave similar result to 1st instar larvae or 2~4 instar larvae, suggesting a possibility that there is an attractant(s) in the hot-pepper fruits.

• Korean Journal of Plant Tissue Culture
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• v.26 no.4
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• pp.245-250
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• 1999

Plantlets derived from leaf blade-segment culture of a variegated tobacco (Nicotiana tabacum L. cv. BY-4) that was induced by a heavy-ion ($^{14}N$) beam irradiation to proembryos, were characterized. When explants from both white and green sections of leaves of the variegated plant were cultured on MS medium containing 0.1 mg/L NAA and 1.0 mg/L BAP, the white sections yielded only white shoots, whereas the green sections generated approximately 47.2% green, 37.4% white and 15.4% variegated shoots. In the F1 generation of a green tobacco derived from the leaf blade-segment culture, the segregation ratio of green to white was 1,651:54. Furthermore, reciprocal crosses showed that all of the progenies was green, indicating that the variegation is not maternally inherited. When the signal intensity of photosynthesis genes was determined by DNA gel blot analysis using the variegated leaves derived from green sections of variegated leaves, there were more of the rbcL, psbA, 16S rDNA and 23S rDNA chloroplast genes in the white sections than the chloroplast genes in wild type and green sections of the variegated plants.

• Journal of the Korean Society of Tobacco Science
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• v.7 no.2
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• pp.141-149
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• 1985

뿌리에서 흡수된 질소는 대부분이 질산태이온으로 잎의 엽맥까지 도달하나 엽육에서 급격히 환원되어 유기태질소로 동화한다. 잎의 주맥을 통과하여 세맥까지 질산태질소로 이동되며 전질소의 1/2이상의 양까지 다다르나 엽육에서는 전질소함량이 엽맥의 5배까지 증가되어도 질산태질소는 $10^{-2}$ 정도로 급격히 환원되었다. 칼륨은 엽맥까지 질소와 동반 이동하나 엽육에서의 질산태질소환원에 의하여 이동이 차단되는 현상을 보였다. 엽육에 축적된 칼륨은 능금산의 축전을 촉진하였고 질산환원효소의 활성이 왕성하게 일어나는 하위엽에 높은 농도로 축적되었다.

• Korean Journal of Weed Science
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• v.18 no.1
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• pp.69-75
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• 1998

Responses of tobacco(Nicotiana tabacum cv. Xanthi) leaves of different age to diphenyl ether herbicide oxyfluorfen were evaluated with respect to cellular leakage, chlorophyll loss, and membrane lipid peroxidation. When tobacco leaves of different age were incubated under light condition at $25^{\circ}C$ following 12hr dark incubation. Significant electrolyte leakage from the treated tissues into the bathing medium occurred. The change of electrolyte leakage was proportional to the oxytluorfen concentration and the duration of light exposure to the tissues. Electrolyte leakage from the tissues treated with oxyfluorfen was highly dependent on the leaf age. From the tissues of younger age, more electrolyte leakage occurred and lag period was greatly reduced. Chlorophyll loss and membrane lipid peroxidation, as measured by malondialdehyde production, caused by oxyfluorfen treatment were also dependent an the age of treated leaf tissues. In conclusion, physiological responses of tobacco leaves to oxyfluorfen greatly varied with the age of treated tissues, and thus tobacco plants could be used as appropriate materials for studying the mechanisms of tolerance to diphenyl ether herbicides.

• Korean Journal Plant Pathology
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• v.3 no.3
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• pp.203-209
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• 1987

The substances obtained from the leaf, stem and root of tobacco plants inoculated with avirulent and virulent isolates of Pseudomonas solanacearum were at R_f\;0.6$ and R_f\;0.9$ on TLC plate, respectively. Both substances showed antibacterial activities not only on P. solanacearum but also on Erwinia carotovora subsp. carotovora and Escherichia coli in vitro. However, the antibacterial substances were not detectable from the filtrate of the autoclaves tobacco sap medium, in which the avirulent or virulent bacterium was cultured for 3 days. Peroxidase and poly phenoloxidase activities and their isozyme patterns did not differ significantly between plants treated with the virulent and avirulent isolates, or between the susceptible cultivar BY 4 and the resistant cultivar NC 82. However, activities of the two enzymes were increased in leaves of the susceptible cultivar BY 4 treated with either the virulent or the avirulent isolate.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.5
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• pp.632-639
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• 1997

The experiment which imposed the water stress to tobacco(Nicotiana tabacum L.) plant was carried at the late of maximum growth period. In order to know the influence of drought stress on the growth and developmemt of tobacco leaves of different position and to elucidate the physiological response of plant to various soil water content, stomatal conductance, and leaf water potential were measured. The drought stress at the maximum growth period negatively affected to the overall growth characteristics of shoot. The response of the growth was small at the middle and the lower leaves, and great at the upper leaves. The relative water content of upper, middle, and lower leaves at the fifth day after treatment were 74, 64, and 59%, respectively, as soil water content was reduced by 4.3%. This suggested that the wilting point of tobacco leaf was about 75%. The leaf water potential was -0.58 MPa in control and dropped to -1.20 MPa at the fifth day after treatment. This indicated that wilting of leaf may occur at the condition in which the difference of water potential between treatment and control, well watered, was greater than about 20%. Stomatal conductance at the fifth day after treatment dropped from 12 mol /$\textrm{m}^2 sec^{-1}$ to 0.8 mol /$\textrm{m}^2 sec^{-1}$ in the middle and the upper leaves. Stomatal conductance of lower leaves already matured were not affected highly by drought stress at the maximum growth period, but maturing leaves, middle and upper leaves, were highly affected by limitation of soil water.

• Journal of Plant Biology
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• v.35 no.3
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• pp.229-235
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• 1992

Differential expression of the three chlorophyll afb binding (cab) protein gene (cabl, cab2, and cab3) promoters of Arabidopsis thaliana was studied in tobacco plants transformed with cab-CAT (chloramphenicol acetyltransferase) translational fusions. CAT activity was measured to monitor the activities of the cab promoters. The activity of cabi promoter was higher than the other two in transformed tobacco leaves and also in calli and shoots derived from the leaves. Their activities were organ-specific and were the lowest in roots, medium in stems, and the highest in leaves. The relative activity of cabi promoter in stems comparing to it activity in leaves was, however, much higher than the values of cab2 and cab3. When the cab promoter activity was expressed as CAT activity per unit chlorophyll instead of CAT activity per unit protein, the relative cab] promoter activity (stem/leaf) became almost unity. This result suggests that cab2 and cab3 show photosynthetic organ-specificity but cabl does not. Similar result was obtained in the differentiation process of stems and leaves from shoots derived from the transgenic tobacco leaves.leaves.