• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2006.06a
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• pp.17.1-17.1
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• 2006

• Food Science and Preservation
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• v.7 no.2
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• pp.139-144
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• 2000

In order to extend the shelf-life of red chili pepper, MA and CA technology were used. In MA storage, red chili peppers(Jinmi and Jangkun) were packaged in 0.03 mm PE film bags(3 kg/bag) having two holes(${\sigma}$2~3 cm) at 2~3$^{\circ}$C or 7~8$^{\circ}$C. In CA storage, red chili peppers(Jinmi) were stored on following gas composition; 5 or 10% CO$_2$ in combination with 2 or 5% O$_2$ at 2~3$^{\circ}$C, respectively. The changes of weight loss and decay rates during MA storage were less in Jinmi than in Jangkun and less at 2~3$^{\circ}$C storage(except O$_2$ 5%, CO$_2$ 10% condition) while in CA it decreased after 40 days of storage. Red chili peppers would be stored for 30 days when stored in MA conditions(0.03 mm PE film bag) and for 60 days when srored in CA condition on O$_2$ 2%, CO$_2$ 10% based on overall quality of sensory evaluation.

• Korean Journal of Food Science and Technology
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• v.48 no.4
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• pp.317-322
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• 2016

A pesticide mix solution containing difenoconazole, lambda-cyhalothrin, and lufenuron was applied 3 times on field grown chili pepper at a fivefold overdose dilution concentration of the spray solution at a pre-harvest interval of 7 day. Difenoconazole, lambda-cyhalothrin, and lufenuron were detected at 4.43, 0.334, and 1.56 mg/kg, respectively, in raw chili pepper. Washing with water reduced the residue levels to 91.4, 94.3, and 85.3%, respectively. In dried chili pepper, the residues of difenoconazole, lambda-cyhalothrin, and lufenuron were 22.2 mg/kg (processing factor, Pf =5.01), 1.65 mg/kg (Pf =4.94), and 6.54 mg/kg (Pf =4.19). In the seeds, difenoconazole and lambda-cyhalothrin were not detected, and lufenuron was detected at 0.0075 mg/kg (n=1) and <0.005 mg/kg (n=2). Thus the pesticide residues in the seeds was negligible. In the seed oil, difenoconazole and lufenuron residues were 0.0263 and 0.0295 mg/kg, respectively (concentration factors=5.26 and 4.72). These concentration factors supported the theoretical concentration factor of 6.8, assuming that all of compound present in the seed are transferred into the oil.

• Research in Plant Disease
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• v.25 no.3
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• pp.136-142
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• 2019

Drought stress is considered as one of major abiotic stresses; it leads to reduce plant growth and crop productivity. In this study, we selected bacterial strains for alleviating drought stress in chili pepper plants. As drought-tolerant bacteria, 28 among 447 strains were pre-selected by in vitro assays including growth in drought condition with polyethylene glycol and plant growth-promoting traits including production of 1-aminocyclopropane-1-carboxylate deaminase, indole-3-acetic acid and exopolysaccharide. Sequentially, 7 among pre-selected 28 strains were screened based on relative water content (RWC); GLC02 and KJ40, among seven strains were finally selected by RWC and malondialdehyde (MDA) in planta trials under an artificial drought condition by polyethylene glycol solution. Two strains GLC02 and KJ40 reduced drought stress in a natural drought condition as well as an artificial condition. Strains GLC02 or KJ40 increased shoot fresh weight, chlorophyll and stomatal conductance while they decreased MDA in chili pepper plants under a natural drought condition. However, two strains did not show biocontrol activity against diseases caused by Phytophthora capsici and Xanthomonas campestris pv. vesicatoria in chili pepper plants. Taken together, strains GLC02 or KJ40 can be used as bio-fertilizer for alleviation of drought stress in chili pepper plants.

• The Plant Pathology Journal
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• v.26 no.2
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• pp.178-184
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• 2010

Four major diseases of chili pepper including two fungal diseases, anthracnose (Colletotrichum acutatum) and Phytophthora blight (Phytophthora capsici), and two bacterial diseases, bacterial wilt (Ralstonia solanacearum) and bacterial spot (Xanthomonas campestris pv. vesicatoria), were investigated under future climate-change condition treatments in growth chambers. Treatments with elevated $CO_2$ and temperature were maintained at $720ppm{\pm}20ppm$ $CO_2$ and $30^{\circ}C{\pm}0.5^{\circ}C$, whereas ambient conditions were maintained at $420ppm{\pm}20ppm$ $CO_2$ and $25^{\circ}C{\pm}0.5^{\circ}C$. Pepper seedlings or fruits were infected with each pathogen, and then the disease progress was evaluated in the growth chambers. According to paired t-test analyses, bacterial wilt and spot diseases significantly increased by 24% (p=0.008) and 25% (p=0.016), respectively, with elevated $CO_2$ and temperature conditions. On the other hand, neither Phytophthora blight (p=0.906) nor anthracnose (p=0.125) was statistically significant. The elevated $CO_2$ and temperature accelerated the progress of bacterial wilt by two days and bacterial spot by one day compared to the ambient treatment. Temperature regime studies of the diseases without changes in $CO_2$ confirmed that the accelerated bacterial disease progress was mainly due to the increased temperature rather than the elevated $CO_2$ conditions.

• The Plant Pathology Journal
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• v.28 no.2
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• pp.172-184
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• 2012

An infection risk model for Phytophthora blight on chili pepper was developed to estimate the first date of disease occurrence in the field. The model consisted of three parts including estimation of zoosporangium formation, soil water content, and amount of active inoculum in soil. Daily weather data on air temperature, relative humidity and rainfall, and the soil texture data of local areas were used to estimate infection risk level that was quantified as the accumulated amount of active inoculum during the prior three days. Based on the analysis on 190 sets of weather and disease data, it was found that the threshold infection risk of 224 could be an appropriate criterion for determining the primary infection date. The 95% confidence interval for the difference between the estimated date of primary infection and the observed date of first disease occurrence was $8{\pm}3$ days. In the model validation tests, the observed dates of first disease occurrence were within the 95% confidence intervals of the estimated dates in the five out of six cases. The sensitivity analyses suggested that the model was more responsive to temperature and soil texture than relative humidity, rainfall, and transplanting date. The infection risk model could be implemented in practice to control Phytophthora blight in chili pepper fields.

• Journal of Plant Biotechnology
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• v.31 no.3
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• pp.185-190
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• 2004

We established a transient gene expression system in chili pepper leaves based on Agrobacterium-mediated transformation of GUS gene. For the best GUS transient expression, two step culture system was adopted. When the Agrobacterium tumefaciens cell density of pre-culture was $A_{600nm}$ 0.3, the cells were harvested and diluted to $A_{600nm}$ 0.8 with virulence induction medium after cell harvested. The addition of acetosyringone (200 $\mu$M) in virulence induction step was a key factor for successful transient expression. Additionally, Younger leaves showed more effective transient expression than older leaves. Temporally, the strongest intensity of GUS expression was detected at 2 days after infiltration. These results demonstrate that Agrobacterium-mediated transient expression can be used for a simple in vivo assays of plant promoters, transcription factors and furthermore provide efficient protocol for chili pepper transformation.

• The Plant Pathology Journal
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• v.28 no.1
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• pp.81-86
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• 2012

We developed a reassortant RNA virus vector derived from $Cucumber$ $mosaic$ $virus$ (CMV), which has advantages of very wide host range and can efficiently induce gene silencing in a few model plants. Certain CMV isolates, however, show limited host ranges presumably because they naturally co-evolved with their own hosts. We used a reassortant comprised of two strains of CMV, Y-CMV and Gn-CMV, to broaden the host range and to develop a virus vector for virus-induced gene silencing (VIGS). Gn-CMV could infect chili pepper and tomato more efficiently than Y-CMV. Gn-CMV RNA1, 3 and Y-CMV RNA2-A1 vector were newly reconstructed, and the transcript mixture of RNA1 and 3 genomes of Gn-CMV and RNA2 genome of Y-CMV RNA2 containing portions of the endogenous phytoene desaturase (PDS) gene (CMV2A1::PDSs) was inoculated onto chili pepper (cv. Chung-yang), tomato (cvs. Bloody butcher, Tigerella, Silvery fir tree, and Czech bush) and $Nicotiana$ $benthamiana$. All the tested plants infected by the reassortant CMV vector showed typical photo-bleaching phenotypes and reduced expression levels of $PDS$ mRNA. These results suggest that the reassortant CMV vector would be a useful tool for the rapid induction of the RNA silencing of endogenous genes in chili pepper and tomato plants.

• The Plant Pathology Journal
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• v.23 no.3
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• pp.155-160
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• 2007

In order to develop chili pepper bacterial spot resistant cultivars and near-isogenic lines (NILs) to prompt the molecular mapping of the resistance gene, we have run backcross breeding program since 1994. Two resistance genes against Xanthomonas axonopodis pv. vesicatoria Bs2 from Fla. XVR 3-25 and Bs3 from our breeding line 25-11-3-2, were introduced into a land race, Chilseongcho (abbreviated to Chilseong hereafter) with good fruit guality. We report here the testing of $BC_4F_3\;to\;BC_4F_5$. We found that $BC_4F_5$ lines of the crosses were homozygous with respect to the respective genes of introduction. The lines, in which Bs2 gene was introduced, were hypersensitively resistant to both race 1 and race 3 of X. axonopodis pv. vesicatoria, whereas, those in which Bs3 was introduced were resistant to race 1.

• Mycobiology
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• v.45 no.3
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• pp.184-191
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• 2017

The anthracnose disease caused by Colletotrichum species is well-known as a major plant pathogen that primarily causes fruit rot in pepper and reduces its marketability. Thirty-five isolates representing species of Colletotrichum were obtained from chili fruits showing anthracnose disease symptoms in Chungcheongnam-do and Chungcheongbuk-do, South Korea. These 35 isolates were characterized according to morphological characteristics and nucleotide sequence data of internal transcribed spacer, glyceraldehyde-3-phosphate-dehydrogenase, and ${\beta}$-tubulin. The combined dataset shows that all of these 35 isolates were identified as C. scovillei and morphological characteristics were directly correlated with the nucleotide sequence data. Notably, these isolates were recorded for the first time as the causes of anthracnose caused by C. scovillei on pepper in Korea. Forty cultivars were used to investigate the pathogenicity and to identify the possible source of resistance. The result reveals that all of chili cultivars used in this study are susceptible to C. scovillei.