• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.146.2-147
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• 2003

Two Korean isolates of Alfalfa mosaic virus (AHV-AZ, AMV-KR) were isolated from azuki bean and potato plants, respectively, and their pathologies were confirmed on some susceptible host plants including pepper, tobacco and red bean plants. Full length cDNAs to RNA1, RNA2 and RNA3 of the two Korean strains were amplified using the long-template reverse transcription (RT)-polymerase chain reaction (PCR) method. RT-PCR products covering entire regions for the three AMV genome RNAs were cloned. RNA transcripts were synthesized in vitro from each clones using T7 RNA polymerase and infectivity test was peformed in 9 reassortment sets of transcripts. All the combinations of reassorted transcripts were found to be infectious when inoculated onto Nicotiana benthamiana plants, and were not distinguishable to those of wild types. The full-length cDNA clones that were confirmed infectious were sequenced their nucleotide sequences. We will discuss sequence analysis of the two Korean isolates of AMV genomic RNA3 and compare reported foreign isolates of AMV.

• Journal of Bio-Environment Control
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• v.31 no.3
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• pp.204-211
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• 2022

To produce a high quality crop, light is an essential environmental factor in greenhouse cultivation. In the winter season, solar radiation is weak than other season. Therefore, using supplemental light during a low radiation period can increase the crop growth and yield. This study was conducted to select the economical supplemental light source for greenhouse cultivation in pepper during the low radiation period. The green pepper (Capsicum annuum 'Super Cheongyang') was transplanted on 5 September 2019. Supplemental lighting treatment was conducted from 1 January 2020 to 31 March 2020. RB LED (red and blue LED, red:blue = 7:3), W LED (white LED, R:G:B = 5:3:2), and HPS (high-pressure sodium lamp) were used as the supplemental light source. Non-treatment was used as the control. The plant height, SPAD, and number of nodes of pepper plants have no significant differences by supplemental light sources. However, the number of ramifications plants was the greatest in RB LED light source. Moreover, supplemental lighting increased photosynthesis of the pepper plant, and especially, the RB LED had the highest photosynthesis rate during supplemental lighting period. Also, the yield of pepper increased in the supplemental lighting treatment than in the control, and the RB LED had the greatest yield than other light sources. The electricity consumption was the highest in W LED and the lowest in HPS light. Through the economic analysis, the RB LED had high economic efficiency. In conclusion, these results suggest that using RB LED for supplemental light source during low radiation in pepper greenhouse increase the yield and economic feasibility.

• Korean Journal of Microbiology
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• v.49 no.4
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• pp.398-402
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• 2013

This study was to investigate beneficial effects of microbial mixture on red pepper which was capable of promoting plant growth by solubilizing insoluble phosphate as well as protecting plants from pathogenic attack. Saccharomyces sp. L13 was isolated for phosphate solubilizing activity on aluminium phosphate, tricalcium phosphate, calcium hydrophosphate, and magnesium hydrophosphate. On the other hand, Bacillus sp. L32 was isolated for antagonistic activity against Phytophthora capsisi and Colletotrichum gloeosporioides, causing Phytophthora blight and Anthracnose disease in pepper, respectively. The strain L32 exhibited antagonistic activities both under dual culture assays and detached leaves assays. The each strain under the condition of mixed cultivation exhibited the same growth rates as one under pure cultivation. In greenhouse study, the mixed culture showed the both effect of plant growth promotion and reduction of disease symptom development against P. capsisi and C. gloeosporioides providing a potential as effective microbial agent for plant husbandry.

• Microbiology and Biotechnology Letters
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• v.46 no.1
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• pp.77-84
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• 2018

An increase in $CO_2$ will affect plant pathogenic microorganisms, the resistance of host plants, and host-pathogen interactions. This study used Capsicum annuum and Xanthomonas euvesicatoria, a pathogenic bacterium of pepper, to investigate the interactions between hosts and pathogens in conditions of increased $CO_2$ concentrations. Our analysis of disease resistance genes under 800 ppm $CO_2$ using quantitative RT-PCR showed that the expression of CaLRR1, CaPIK1, and PR10 decreased, but that of negative regulator WRKY1 increased. Additionally, the disease progress and severity was higher at 800 ppm than 400 ppm $CO_2$. These results will aid in understanding the interaction between red pepper and X. euvesicatoria under increased $CO_2$ concentrations in the future.

• Korean Journal of Environmental Agriculture
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• v.21 no.2
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• pp.83-89
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• 2002

The effect of low dose $\gamma$ radiation on photosynthesis and the reduction of photoinhibition in red pepper plant was investigated. The seedling height leaf width and leaf length of pepper were stimulated in plants grown from seeds irradiated with the low dose of 4 Gy. The $O_2$ evolution in the 4 Gy irradiation group was 1.5 times greater than in the control. To investigate the effect of low dose $\gamma$ radiation on response to high light stress, photoinhibition was induced in leaves of pepper by illumination of high light (900 $\mu mol/m^2/s$). Pmax was decreased with increasing illumination time by 20% in the control, while hardly decreased in the 4 Gy irradiation group. The photochemical yield of PSII, estimated as Fv/Fm, was decreased with increasing illumination time by 50% after 4 hours while Fo did not change. However, Fv/Fm in the 4 Gy irradiation group was decreased by 37% of inhibition, indicating that the photoinhibition was decreased by the low dose $\gamma$ radiation. Changes in the effective quantum yield of PSII, $\Phi_{PSII}$, and 1/Fo-1/Fm, a measure of the rate constant of excitation trapping by the PSII reaction center, showed similar pattern to Fv/Fm. And NPQ was decreased after photoinhibitory treatment showing no difference between the control and the 4 Gy irradiation group. These results showed the positive effect of low dose $\gamma$ radiation on the seedling growth and the reduction of photoinhibition.

• The Korean Journal of Pesticide Science
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• v.13 no.4
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• pp.283-289
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• 2009

Isolation frequency of resistant isolates of Phytophthora capsici to metalaxyl was reported to be 38.9% through the resistance monitoring for metalaxyl in P. capsici causing pepper Phytophthora blight. Metalaxyl was very effective to mycelium growth, while not to zoosporangium germination and zoospore release. $EC_{50}$ values of metalaxyl in the inhibition of mycelium growth were 0.204, 0.151, 0.379, and $0.215\;{\mu}g\;mL^{-1}$ against each isolate sensitive to the fungicide as P. capsici 06-119, 06-143, P08-7, and P08-31, respectively, whilst those were 5.242, 5.724, 6.621, and $5.377\;{\mu}g\;mL^{-1}$ in P. capsici 06-125, 06-155, P08-50, and P08-60. For the field fitness, several factors, which were mycelium growth, zoosporangium germination, zoospore release, virulence to pepper plants, and the zoosporangium and the oospore production, were investigated with 4 sensitive isolates and 4 resistant isolates. Between 2 groups differentiated by the sensitivity of metalaxyl, there was no significance in mycelium growth, zoosporangium germination, zoospore release, and virulence to pepper plants. However, the zoosporangium and the oospore production in each resistant isolate, which were related to survival of P. capsici in fields, were superior to those of sensitive isolates. Based on results of this study, it was suggested that the increase of the percentage of resistant isolates to metalaxyl resulted from the high capacities of the zoosporangium and the oospore production.

• Korean Journal of Environmental Agriculture
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• v.29 no.2
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• pp.159-164
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• 2010

Imidacloprid is a systemic insecticide which has been used widely in various crops to control insects. In the present study, we demonstrated that pre-treatment of imidacloprid significantly induced tolerance to drought in plant. Relative water content, chlorophyll levels, and recovery rate upon rehydration after drought stress in tobacco plants pre-treated with imidacloprid were higher levels than the control plants. Induced drought tolerance by imidacloprid treatments in red pepper was also demonstrated by measurement of recovery rate and fresh weight upon drought stress. Taken together, our results suggest that imidacloprid, in addition to exerting direct insecticidal activity, may also protect plants by induced tolerance to drought in plant.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.2
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• pp.12-19
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• 2010

This study was carried out to explore the availability of seedling pots made from paper mill sludge using red pepper species called Nokkwang. The seedling pots were made by several conditions such as different mixing ratios between sludge and old newspaper (ONP), sterilizing treatment and latex coating. After 30 day cultivation in a green house, the growth condition of the red peppers was evaluated by comparison with those raised in the plastics seedling pots. The red peppers in the plastics pot showed a better growth than those in the sludge pots. Sterilizing treatment, latex coating and different mixing ratios between paper sludges and ONP did rarely affect a growth rate of the plant and the contents of inorganic elements. However, latex coating contributed to protection of physical structure of the sludge pots in spite of constant water feeding. Even though some inorganic elements from the sludge pots migrated into the bed soils, electronic conductivity of the bed soils was within the proper range for the plant growth. Finally it was confirmed that the seedling pots made from paper mill sludges could be used to cultivate horticultural plants as the alternative to the plastics pots.

• Korean Journal of Environmental Agriculture
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• v.34 no.4
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• pp.260-267
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• 2015

BACKGROUND: The current study was conducted to examine the species specific accumulation of Cd and Pb in 11 crop species (Soybean, Sesame, Corn, Polished rice, Carrot, Potato, Garlic, Spring onion, Chinese leek, Red pepper, Eggplant), through cultivating them under the same condition with metal contaminated soils.METHODS AND RESULTS: Eleven crop species were cultivated in three different soils contaminated with Cd and Pb and harvested. Edible parts of each crop was pretreated and analyzed to determine Cd and Pb concentrations, and subsequently bioconcentration factors (BCFs) were calculated. In general, the crops of which seeds are used as food showed high concentrations of both Cd and Pb. For instance, Cd concentrations in crops cultivated in Soil A was in the order of soybean (0.432 mg kg^-1) > sesame (0.385) > polished rice (0.176) > carrot (0.116) > corn (0.060) > red pepper > (0.047) > potato (0.044) > egg plant (0.025) > garlic (0.023) > spring onion (0.016) > Chinese leek (0.011). BCFs showed the same order.CONCLUSION: From this study, it can be conclude that seeds plants should not be cultivated in Cd and Pb contaminated soils to secure food safety from metal contaminated soils.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.659-664
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• 2013

The aim of this study is to determine the drought stress index through photochemical analysis in red pepper (Capsiumannuum L.). The photochemical interpretation was performed in the basis of the relation between Kautsky effect and Photosystem II (PSII) following the measurement of chlorophyll, pheophytin contents, and $CO_2$ assimilation in drought stressed 5-week-old red pepper plants. The $CO_2$ assimilation rate was severely lowered with almost 77% reduction of chlorophyll and pheophytin contents at four days after non-irrigation. It was clearly observed that the chlorophyll fluorescence intensity rose from a minimum level (the O level), in less than one second, to a maximum level (the P-level) via two intermediate steps labeled J and I (OJIP process). Drought factor index (DFI) was also calculated using measured OJIP parameters. The DFI was -0.22, meaning not only the initial inhibition of PSII but also sequential inhibition of PSI. In real, most of all photochemical parameters such as quantum yield of the electron transport flux from Quinone A ($Q_A$) to Quinone B ($Q_B$), quantum yield of the electron transport flux until the PSI electron acceptors, quantum yield of the electron transport flux until the PSI electron acceptors, average absorbed photon flux per PSII reaction center, and electron transport flux until PSI acceptors per cross section were profoundly reduced except number of QA reducing reaction centers (RCs) per PSII antenna chlorophyll (RC/ABS). It was illuminated that at least 6 parameters related with quantum yield/efficiency and specific energy fluxes (per active PSII RC) could be applied to be used as the drought stress index. Furthermore, in the combination of parameters, driving forces (DF) for photochemical activity could be deduced from the performance index (PI) for energy conservation from photons absorbed by PSII antenna until the reduction of PSI acceptors. In conclusion, photochemical responses and their related parameters can be used as physiological DFI.