• 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

• Proceedings of the Korean Society of Life Science Conference
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• 2008.10a
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• pp.70.1-70.1
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• 2008

• Proceedings of the Botanical Society of Korea Conference
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• 2002.04a
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• pp.107-107
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• 2002

• The Plant Pathology Journal
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• v.26 no.4
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• pp.340-345
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• 2010

Two similar microbial fungicides (termed as MA and MB) developed in a Korean biopesticide company were analyzed and compared each other in their biocontrol activities against the phytophthora blight of chili pepper caused by Phytophthora capsici. MA and MB contained the microbe Paenibacillus polymyxa and Bacillus subtilis, respectively, with concentrations over those posted on the microbial products. In comparison of the isolated microbes (termed as MAP from MA and MBB from MB) in the antagonistic activities against P. capsici was effective, prominently against zoospore germination, while MBB only significantly inhibited the mycelia growth of the pathogen. Some effectiveness of MAP and MBB was noted in the inhibition of zoosporangium formation and zoospore release from zoosporangia; however, no such large difference between MAP and MBB was noted. In a pot experiment, MA reduced the severity of the phytophthora blight more than MB, suggesting that the disease control efficacy would be more attributable to the inhibition of zoospore germination than mycelia growth of P. capsici. These results also suggest that the similar microbes MA and MB targeting different points in the life cycle of the pathogen differ in the disease control efficacies. Therefore, to develop microbial fungicides it is required to examine the targeting points in the pathogen's life cycle as well as the action mode of antagonistic microorganisms.

• Journal of Environmental Health Sciences
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• v.43 no.4
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• pp.280-297
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• 2017

Objectives: We assessed pesticide exposure levels according to cultivation and crop type and investigated agricultural factors related to exposure. Methods: The participants, 341 male and 127 female farmers, were divided into three groups by cultivation crop type: chili greenhouse, cucumber greenhouse, and orchard. We collected questionnaires, socioeconomic characteristics and agricultural factors, and spot urine. Pesticide exposure was examined using four organophosphate and four pyrethroids urinary metabolites: dimethylphosphate, dimethylthiophosphate, diethylphosphate, diethylthiophosphate, Cis and Trans-3-(2-2dichlorovinyl)-2, 2-dimethylcyclopropane carboxylic acid, 3-phenoxybenzoic acid (3-PBA), Cis-3-(2-2dibrmovinyl)-2, and 2-dimethylcyclopropane carboxylic acid. Each metabolite was summed ${\Sigma}DAP$ and ${\Sigma}PY$ according to the chemical class. Results: Urinary metabolite detection rates and concentrations were similar between the greenhouse groups, but the orchard group was different. Similar 3-PBA detection rates were found in the three groups, but the geometric mean was very high in the orchard group compared to the two greenhouse groups. 3-PBA concentration in the orchard group was $4.11{\mu}g/g$ creatinine; the chili and cucumber greenhouse groups were 1.27 and $1.16{\mu}g/g$ creatinine, respectively. ${\Sigma}DAP$ was significantly associated with cultivation crop type and seasonal variation, but ${\Sigma}PY$ was not relevant. Conclusions: Our results suggest that cultivation and crop type may be correlated with different pesticide types and exposure levels. Furthermore, seasonal factors were related as potential factors influencing the level of organophosphate metabolites, but not for pyrethroid metabolites.

• Current Research on Agriculture and Life Sciences
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• v.8
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• pp.35-44
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• 1990

Sixty two lines of pepper including Korean local cultivars and introductions were planted out to the experiment farm of Kyungpook National University for seed increase, and 16 plant and fruit characters including days to flower were recorded. In days to flower, KC85(Chilgok Dongmyung) and KC116(PI308791), KC154(Cherry Sweet), and KC185(Choseongochu) were the earliest with 83 days, and KC139(Serrano chili) and KC103(PI297488) were the latest with 126 days. In fruit detachment force, KC85(Chilgok dongmyung) was the tenderest with 0.45kg and KC162(PI22444) was the toughest with 3.34kg. In powdery mildew incidence, KC10(Pimiento), KC23(PI224423), KC51(PI257044), KC56(PI257053), KC126(PI358812), KC119(PI322719), KC143(Emerald Giant), KC148(VR-2), KC163(PI224445), KC163(Papari Mild) were the least diseased. Anthracnose was least on KC39(Serrano Chili). Collection and introduction of pepper germplasm was continued. Fourteen Korean local cultivars and 25 foreign cultivars including 2 wild species were additionally collected or introduced.

• Korean Journal of Agricultural Science
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• v.45 no.1
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• pp.19-27
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• 2018

To study the effect of natural anti-microbial chemicals on the growth and quality of chili peppers, chitosan ($100mg/L^{-1}$), stevia ($250mg/L^{-1}$), and the mixture of both chemicals at the same concentration were sprayed after planting at 1-week interval throughout the experimental period. Plant height was measured twice after the $3^{rd}$ and $4^{th}$ applications. Plant height was numerically reduced in all chemical treatments compared to that of untreated control; however, there was no statistical difference between treatments. The fruit quality was examined at commercial maturity, and only minor differences were found in fruit color, length, and dry matter content between the treatments. Although a statistical difference was not present for soluble sugars levels, total phenolics, and capsaicin contents, yield in all chemical treatments significantly increased compared to untreated control. The effect on yield increase was greater at the late harvest season regardless of treatments. Total yield of 4 harvests was higher for the chitosan treatment than other treatments. During the experiment, the entire experimental field was waterlogged for 1 day due to sudden heavy rainfall, which resulted in the occurrence of bacterial browning disease in all treatments. The rate of disease occurrence and the degree of severity, however, were much lower in the chitosan treatment. In conclusion, the potential of chitosan as an alternative antimicrobial agent was confirmed in chili peppers in this study. Further research is required on stevia as an alternative chemical for disease control in chili peppers.

• Horticultural Science & Technology
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• v.34 no.2
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• pp.282-293
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• 2016

Root-knot nematodes (Meloidogyne spp.) are major plant pathogens that cause reductions in yield and quality of several solanaceous crops, including pepper (Capsicum spp.). These losses can be averted through planting of resistant cultivars. Plants are defined as resistant when they suppress nematode reproduction. In this study, the resistance degrees of 102 commercial cultivars of chili pepper (Capsicum annuum) to a root-knot nematode, Meloidogyne incognita, were evaluated by comparing the number of egg masses on their roots to those of 'PR huimangchan', a highly susceptible cultivar that exhibited the most egg masses of the chili pepper cultivars evaluated. Among these cultivars, forty-four (43.1%) showed resistance to M. incognita and eighteen (17.6%) were moderately resistant. The other cultivars (39.3%) were determined to be susceptible. For further study, six chili pepper cultivars (i.e., Gangryeokjosenggeon, Shinsegae, Muhanjilju, PR Bulrocho, PR Huimangchan, and Jjang) with different levels of resistance to the nematode were selected. Changes in resistance of the six cultivars under several conditions, such as inoculum concentration, plant growth stage, and cultivation period after transplanting were investigated. We found that an efficient screening method for resistance of chili pepper to M. incognita is to transplant the chili pepper seedlings 7 days before inoculation, to inoculate 28-day-old plants with M. incognita by loading 5,000 eggs per plant into the pot of soil, to cultivate the plants in a greenhouse ($25{\pm}5^{\circ}C$) for 45-60 days, to measure the number of egg masses on roots of the seedlings, and then to determine the resistance response of the plants by comparing the number of egg masses on the roots with a reference-susceptible cultivar 'PR huimangchan'.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2005.10a
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• pp.70-72
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• 2005

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2018.06a
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• pp.107-108
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• 2018