• Korean Journal of Plant Tissue Culture
• /
• v.27 no.6
• /
• pp.469-474
• /
• 2000

Effect of the antibiotic carbenicillin on callus and shoot formation from the leaf disc culture of tobacco (Nicotiana tabacum L. cv. BY-4) was examined. The number of shoot induced from the leaf explants was decreased as the amount of carbenicillin increased from 250 mg/L to 2,000 mg/L on MS medium containing 0.5 mg/L of BAP or kinetin. In addition, calli formation from the leaf explants was increased by the treatment of 250 mg/L ∼ 500 mg/L carbenicillin with or without 0.5 mg/L of 2,4-D or NAA. However, the fresh weight of 4-week-cultured explants was decreased with increasing carbenicillin from 250 mg/L to 2,000 mg/L on MS medium containing 0.5 mg/L of 2,4-D or NAA. These results indicate that carbenicillin has an auxin-like effect, such as promoting callus formation and inhibiting shoot induction. It leads to the conclusion that the auxin-like property should be taken into account for the production of transgenic plants via Agrobacterium-mediated transformation.

• Journal of the Korean Society of Tobacco Science
• /
• v.11 no.1
• /
• pp.11-17
• /
• 1989

Inhibition of tobacco mosaic virus (TMV) infection by 4 surfactants, sodium salts of alpha olefin (AOS), linear alkylbenzene (LAS), dioctyl sulfosuccinate (OSS), and dodecyl benzene sulfonic acid (SAS), was examined on tobacco cv. Xanthi-nc and NC 82. Infection of virions or TMV RNA was inhibited over 98% by the surfactants (2500 rpm). However, symptom development and viral concentration in tobacco plants treated with the surfactants into the rhizosphere soil 3 days before inoculation with TMV on leaves were not different from those in untreated tobacco plants. This indicates no significant systemic effects of the surfactants on the inhibition of TMV infection. The surfactants, except LAS, had no effect on the inhibition of viral infection when purified virions mixed with each surfactant and ultracentrifuged were inoculated on the tobacco plants. The virus was almost inactivated by LAS, showing that the viral infection was reduced more than 96%. The virus particles treated with the surfactants were not distinguishable in size and dimension from untreated normal particles, suggesting that the inhibitory action of the surfactants to TMV infection may not involve disintergration or uncoating of the virus at the early stage of infection.

• The Journal of Natural Sciences
• /
• v.10 no.1
• /
• pp.23-26
• /
• 1998

The efficacy of various concentration of divalent copper and zinc ions was evaluated separately for the infectivity of tobacco mosaic virus. Infectivity of TMV was more enhanced by addition of zinc, while it was decreased by addition of copper. The number of local lesions were more produced on tobacco leaves inoculated with inoculum sap containing zinc than those inoculated with sap only. The effect of copper inhibited the infectivity of TMV is dependent on copper concentration. TMV particles treated with various concentration of zinc and copper, respectively, analyzed by electrophoresis, and appeared to be altered in electrophoretic behavior. When TMV was exposed to zinc concentration at more than 200mM, the viral particles were completely degraded, and at 40-20 mM they were barely detectable, but at 2 mM they were quite stable. When TMV was exposed at less than concentration of 20 mM of copper were degraded.

• Korean journal of applied entomology
• /
• v.49 no.4
• /
• pp.351-355
• /
• 2010

This study was conducted to determine the relationship of larval density of tobacco cutworm, Spodoptera litura (Fabricius) to damage in greenhouse sweet pepper. Laboratory experiments, cage experiments by artificial release and field investigation were carried out in 2008. The leaf consumption rate increased greatly with larval development. The damaged leaves had several round or oval shape holes on the surface or lost certain parts of them, and the fruit damaged had a conspicuous hole on the surface or scar marks around the calyx. In the field investigation, fruit damage was highly correlated with larval densities and reached 3.5% damage at maximum. Cage experiments showed that numbers of non-marketable fruit increased as increasing larval densities released. The larval density at two weeks before harvest had a high relationship with the percentage of damaged-fruit at harvest. Corresponding larval density caused 1, 3, 5% of damaged-fruit was 0.2, 0.5, 0.8 larvae per plant, respectively.

• Korean journal of applied entomology
• /
• v.27 no.4
• /
• pp.219-224
• /
• 1988

Rearing of Spodoptera litura fed on arfificial diet basically formulated with kindby bean powder was much promisible for production of S. litura nuclear polyhedrosis virus(SINPV) than that on kidney bean leaves. The $LC_{50}$ of SINPV against 3rd and 5th instar were $4.48{\times}10^{3}$ PIB/ml and $4.52{\times}10^{4}$ PIB/ml, respectively. The $LC_{50}${/TEX} of SINPV varied from 5.8 days to 7.7 days at higher inocula in the testes. The larval growth of 1st and 3rd instar larvae fed on virus were much delayed and the larval were killed within 4th instar in the former and within 5th instar in latter. S. litura larvae were very susceptible to multinucleocapsid nuclear polyhedsosis virus (MNPV) of Autographa californica, S. littoralis and Trichoplusia ni.

• Applied Chemistry for Engineering
• /
• v.25 no.5
• /
• pp.538-543
• /
• 2014

In order to substitute for the marketed horseradish peroxidase, a hydrogen peroxide sensor embedded with tobacco leaf in carbon pastes was constructed and its sensing ability was electrochemically evaluated. Ten and more electrode parameters obtained implied that the enzyme electrode exerts its remarkable specificity quantitatively in the experimental range of potential. Especially the small symmetry factor (${\alpha}$, 0.21) showed that the electrode kinetics is very sensitive to the change of electrode potential. The experimental facts above suggested that our enzyme electrode functions as a hydrogen peroxide sensor normally and tobacco peroxidase can be used in the place of the marketed one as an alternative to marketed ones.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.41 no.5
• /
• pp.563-568
• /
• 1996

This experiment was conducted to obtain basic information of biochemical changes in the process of senescence by measuring the total RNA, protein, protease activity and electrophoretic pattern of protein in tobacco plant. The content of soluble protein increased by 15 days after leaf emergence and its level was not changed from 15 to 35 days after leaf emergence. The content of total RNA showed a maximum value at 15 days after leaf emergence and then decreased rapidly until 30 days after leaf emergence. The activity of protease of neutral fraction was higher than that of acidic fraction and rapidly increased up to the end of senescence after 50 days after leaf emergence. According to the analysis of electrophoresis, polypeptide band of 61kd was developed after 35 days after leaf emergence and increased by the end of senescence.

• Korean journal of applied entomology
• /
• v.28 no.3
• /
• pp.113-119
• /
• 1989

Larval development and adult oviposition of the Oriental tobacco budworm, Heliothis assulta were examined with tobacco leaves sprayed with aqueous or ethanolic extracts from ten selected wild plant species. High larval mortality was observed with extracts from Rhamnus davurice. Persicaria hydroPiPer, Forsythia koreana, Trifolium repens, Styrax japonica, Ginkgo bi/oba, and vilis amurensis. Most of larval mortality occurred during first and second instar, apparently due to antifeeding effects of plant extracts. These extracts also prolonged developmental period of survived larvae and increased the number of larval molts. Oviposition was not affected as much as the larval mortality, but Rhamnus davurice and Styrax jaPonica extracts reduced the number of eggs laid by more than fifty percent.

• Korean Journal of Organic Agriculture
• /
• v.24 no.4
• /
• pp.809-819
• /
• 2016

This experiment was carried out to determine the treatment interval on neem product for control of Bemisia tabaci on eggplant using eco-friendly agriculture. We have investigated the control effect of B. tabaci, growth characteristics of eggplant, economics according to neem product treatment interval on eggplant. The longer neem processing interval tended to decrease control effect on nymphs of B. tabaci. Control effect of nymph of B. tabaci according to treatment interval of 3 days, 5 days, 7 days, 10 days, and 15 days were 96.7%, 89.7%, 76.1%, 73.4%, and 51.0%, respectively. This result was the same tendency in adult of B. tabaci control effects on eggplant. Growth characteristics of eggplant according to neem the treatment interval of 3 days, 5 days, and 7 days, was less damaged on of B. tabaci. However, the 10 days, 15 days, and untreated of neem treatment intervals were badly damaged by B. tabaci. Therefore, neem treatment interval of 3~7 days for control of B. tabaci was high control effect. However, it is considered to be the most suitable to process every seven days considering the economics and so on. The results of economic analysis from income of 7 days neem treatment interval was the most high as 19.505 thousand won per 10a and the most economical treatment for control of B. tabaci.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.41 no.2
• /
• pp.200-206
• /
• 1996

Experiment was conducted to get the information about physico-chemical properties of flue-cured tobacco on the degree of maturity cultivated in paddy-upland rotated field, and compared to upland ones. For the samples of this experiment, 3~4 leaves at each stalk position were harvested from the bottom of plants. Physico-chemical properties of cured leaves were determined from the samples collected at weekly intervals, and of obtained from 4 stalk positions. For the degree of maturity, harvested leaves were separated with visual characters into four classes such as immature, mature, ripe, and mellow. Regardless of stalk position, the order of shrinkage rate with length and width of leaves was mellow> immature> ripe> mature, and ripe leaves from paddy field showed higher shrinkage rate than those of upland. Nicotine and total nitrogen contents were decreased with the degree of maturity while reducing sugar content were showed a reverse tendency. Ripe leaves from paddy field had lower reducing sugar contents, comparing with upland tobacco. Filling capacity of cured leaves from paddy field was decreased with degree of maturity, but there was no difference between upland and paddy tobacco. Shatter index was increased in the oeder of immature > mellow > mature > ripe. Chemical components of cigarette smoke from paddy field tobacco were little higher in $CO_2$ total particulate matter and tar contents, while combustibility was little lower than that of upland tobacco. It was also evaluated that paddy field tobacco was unfavorable for the non-volatile organic and higher fatty acids contents comparing with upland tobacco.