• Journal of Bio-Environment Control
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• v.24 no.3
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• pp.243-251
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• 2015

This study aimed to determine the effects of root zone cooling using air duct on air temperature distribution and root zone and leaf temperatures of sweet pepper (Capsicum annum L. 'Veyron') grown on coir substrate hydroponic system in a greenhouse. When the air duct was laid at the passage adjacent the slab, the direction of air blowing was upstream at $45^{\circ}$. The cooling temperature was set at $20^{\circ}C$ for day and $18^{\circ}C$ for night. For cooing timing treatments, the cooling air was applied at all day (All-day), only night time (5 p.m. to 1 a.m.; Night), or no cooling (Control). The air temperature inside the greenhouse at a height of 40 and 80cm above the floor, and substrate and leaf temperatures, fruit characteristics, and fruit ratio were measured. Under the All-day treatment, the air temperature was decreased about $4.4{\sim}5.1^{\circ}C$ at the height of 40cm and $2.1{\sim}3.1^{\circ}C$ at the height of 80cm. Under the Night treatment, the air temperature was decreased about $3.4{\sim}3.8^{\circ}C$ at the height of 40cm and $2.2{\sim}2.7^{\circ}C$ at the height of 80cm. The daily average temperature in the substrate was in the order of the Control ($27.7^{\circ}C$) > Night ($24.1^{\circ}C$) > All-day ($22.8^{\circ}C$) treatment. Cooling the passage with either upstream blowing at $45^{\circ}$ or horizontal blowing at $180^{\circ}$ was effective in lowering the air temperature at a height of 50cm; however, no difference at a height of 100cm. Cooling the passage with perpendicular direction at $90^{\circ}$ was effective in lowering the air temperature at the height between 100 and 200cm above the floor; however, no effect on the temperature at the height of 50cm. A greater decrease in leaf temperature was found at 7 p.m. than that at 9. a.m. under both All-day and Night treatments. Fresh weight partitioning of fruit was in the order of the All-day (48.6%) > Night (45.6%) > Control (24.4%) treatment. A higher fruit production was observed under the All-day treatment, in which the accumulated average temperature was the lowest, and it may have been led to a higher proportion of photosynthate distributed to fruit than other treatments.

• Horticultural Science & Technology
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• v.29 no.4
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• pp.317-325
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• 2011

This study was conducted to examine the effect of supplemental lighting on the growth and yield of hydroponically grown sweet pepper (Capsicum annuum L. cv. sprit) under low levels of natural light in winter. The plants were treated with natural light only (control), 3-hour supplemental lighting before sunrise, after sunrise and after sunset with high pressure sodium (HPS, 400W). As the result of these three treatments, the supplemental lighting promoted photosynthesis in the low light intensity condition and particularly photosynthesis was more active right after sun rise in the morning, 1.5-$3.0{\mu}molCO_2{\cdot}m^{-2}{\cdot}s^{-1}$ comparing to those of supplemental lighting after sunset, 0.5-$1.5{\mu}molCO_2{\cdot}m^{-2}{\cdot}s^{-1}$. Transpiration rate and stomatal conductance sharply increased with supplemental lighting after sunrise then they decreased again after turning the lights off. Stomatal size was observed $32.2{\mu}m^2$ after supplemental lighting, whereas the size of the natural light was almost closed at $7.7{\mu}m^2$. The average plant height of sweet papper cv. spirit was 185 cm before sunrise, 188 cm after sunrise and 208 cm after sunset with supplemental lighting for 3hours while the control was 171 cm. With supplemental lighting a better number of fruit set per plant was measured 4.3 before and after sunrise, 3.7 after sunset but 2.6 in the control. Interestingly, there were no significant differences in the sugar content ($^{\circ}Brix$) degree between treatment of supplemental lighting, whereas slight differences between seasons were seen. The marketable fruit yield of sweet pepper (cv. spirit) was $116.0kg{\cdot}ha$ with supplemental lighting, whereas the control (natural light only) was $75.8kg{\cdot}ha$. Despite of spending electricity and depreciation cost, the economic analysis showed net income with supplemental lighting after sunrise was 51% higher than control treatment in cv. spirit.

• Journal of Bio-Environment Control
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• v.4 no.2
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• pp.152-158
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• 1995

This experiment was undertaken in order to clarify effect of NO$_3$-N/NH$_4$-N ratios(NO$_3$/NH$_4$ : 10:0, 8:2) in the nutrient solution on growth, yield, photosynthetic rate, relative concentration of chlorophyll and root activity of hydroponically grown pepper plants at three different root- zone temperatures of 18$^{\circ}C$, 22$^{\circ}C$ and 26$^{\circ}C$. Plant height, leaf number, stem diameter, fresh and dry weight of leaf and root were no effect in by three root- zone temperatures. However, leaf number, stem diameter, fresh and dry weight of leaf and stem, dry weight of root at 18$^{\circ}C$, 22$^{\circ}C$ and $25^{\circ}C$ increased when NH$_4$-N was added to the solution. Under root-Bone temperatures of 18$^{\circ}C$, 26$^{\circ}C$ condition, fruit length were longer by the addition of NH$_4$-N. Fruit number and yield increased by the addition of NH$_4$-N at three root-zone temperatures. Photosynthetic rate decreased as root - zone temperature increased. Under root-zone temperatures of 18$^{\circ}C$, 22$^{\circ}C$ and 26$^{\circ}C$ condition, photosynthetic rate increased significantly by the addition of NH$_4$-N. Chlorophyll content of plants increased at 22$^{\circ}C$. Under root-zone temperatures of 18$^{\circ}C$, 22$^{\circ}C$ and 26$^{\circ}C$ condition, chlorophyll content of plants increased by the addition of NH$_4$-N. Root activity of increased at 26$^{\circ}C$ Under root-Bone temperatures of 18$^{\circ}C$, 22$^{\circ}C$ and 26$^{\circ}C$ condition, root activity increased by the addition of NH$_4$- N.

• Research in Plant Disease
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• v.17 no.3
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• pp.334-341
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• 2011

The kinds of crop requested from agricultural actual places of famers, Agricultural extension services and so forth was 8 including red pepper for vegetables, 4 including apple for fruit trees and 6 including chrysanthemum for flowers in 2010. The important vegetables in clinical diagnosis of viral diseases were tomato, watermelon and red pepper having the requested rate of 31.8%, 21.4% and 19.5%, respectively. On fruit trees, grape and apple were most common with the requested rate of 63.6% and 33.0%, orderly. On floral crops, tulip and cactus were damaged by viral diseases with the requested rate of 60.0% and 20.0%, orderly. On peppers and tomatoes, six viruses including Cucumber mosaic virus (CMV) and Broad bean wilt virus 2 (BBWV2) infected. Five viruses including Melon necrotic spot virus (MNSV) and CMV were identified from watermelons. On grapes, six viruses including Grapevine fleck virus (GFkV) infected. CMV was identified from six vegetables including pepper out of 8 kinds of vegetables and tulip plant. Total agents of virus and viroid species were 32 and 4 species, respectively, in 2010. Tomato yellow leaf curl disease by Tomato yellow leaf curl virus and Tobacco yellow leaf curl virus was occurred newly at 18 Si/Gun areas including Buan, Jeonbuk province in 2010 and the total areas were increased up to 58 Si/Gun from the first incidence in 2008. Tomato spotted wilt virus (TSWV) occurred newly at two areas of Jinan, Jeonbuk and Jeju in Jeju province in 2010, and the incidence areas were expanded to 25 Si/Gun areas from severe occurrence at Anyang area in 2004. No incidence of TSWV was recorded only in Gyeongbuk and Chungbuk province. Tomato bushy stunt virus occurred newly at Jinju, Gyeongnam, and it had the total incidence areas of 5 Si/Gun after first observation at Sacheon, Gyeongnam in 2004.

• Research in Plant Disease
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• v.20 no.4
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• pp.299-302
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• 2014

The Paprika plant infected with Pepper mild mottle virus (PMMoV) do not produce commercial fruit as causing necrotic spots symptom on the fruit. Ten cultivars of paprika were analyzed to select the resistance cultivars against PMMoV pathotypes, $P_{1.2}$ and $P_{1.2.3}$, using bioassay and genetic markers. $L^1$, $L^3$, and $L^4$ genotypes expressing resistance to the pathotypes existed in those cultivars but $L^2$ genotype did not. $L^4L^4$ in cvs. Easy and Magnifico, $L^4L^3$ in cvs. Scirocco and Orange glory F1, $L^4L^1$ in cv. Special F1, $L^3L^3$ in cvs. Fiesta, Piero and Derby, and $L^3L^1$ in Cupra and Mazzona F1 were identified with SCAR and CAPS markers. The resistant cvs. to the 2 pathotypes were Magnipico, Easy, Scirocco F1, Orange glory and Special F1 and the susceptible cvs. were Fiesta, Piero, Derby, Cupra and Mazzona F1. The susceptible cvs. of the absence of $L^4$ genotype showed systemic infection when inoculated with PMMoV-$P_{1.2.3}$. However, those cvs. despite the presence of $L^3$ genotype showed vein necrosis on the inoculated leaf and hypersensitive necrosis symptom on the upper parts when inoculated with PMMoV-$P_{1.2}$.

• The Korean Journal of Pesticide Science
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• v.15 no.3
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• pp.246-253
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• 2011

This experiment was carried out to examine the residual amount variation of carbendazim and chlorpyrifos in fruit parts of red pepper according to the open field and/or the rain shelter house. It was shown higher residual amounts of agrochemicals in the field than the house condition at two hours (0 day) after chemical application, but it was shown higher residual amounts in the house at 5 days and 10 days. Although the residual amount in the field was higher than in the house at the beginning, the chemicals fast degraded in field condition. Carbendazim and chlorpyrifos remained as time passed in order of receptacle, but the residual amounts of two chemicals in leaf at $5^{th}$ day. Carbendazim and chlorpyrifos were lessened until 10 days after chemical application, and reduction rate were 19.1% and 66.4% in flesh, 45.2% and 62.3% in receptacle, and 41.6% and 72.0% in the stalk, respectively. The reduction rate at 15 days showed 31.1%, 75.3% in flesh, 43.5%, 81.7% in receptacle, and 47.7%, 82.8% in stalk, respectively. Therefore the reduction rate of carbendazim showed receptacle > stalk > flesh, and that of chlorpyrifos showed stalk > receptacle > flesh in order. The calculated half-life of carbendazim showed 29.6 days in flesh, 13.6 days in receptacle, and 16.0 days in stalk, but that of chlorpyrifos showed 8.3 days in flesh, 8.3 days in receptacle, and 6.3 days in stalk. In conclusion, the half-life of carbendazim was longer than that of chlorpyrifos in even part, and especially was longest in flesh part of fruit.

• Research in Plant Disease
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• v.18 no.1
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• pp.1-9
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• 2012

A total of 20 agricultural organic materials including inorganic compounds, plant oils and plant extracts were used in the study for assessing the control efficacy on pepper diseases. Among inorganic compounds, only copper hydroxide showed inhibitory effect on both Phytophthora capsici causing Phytophthora blight and Colletotrichum acutatum causing anthracnose. Phosphorous acid inhibited the growth of P. capsici on PDA, and Sulfur/quicklime had it on that of C. acutatum. Plant essential oil, rosemary oil, and rapeseed oil among plant oils and plant extract of Japanese apricot/ginkgo nut inhibited the mycelial growth of the two pathogens. In the screening using pepper plant seedlings, the control efficacy on Phytophthora blight in 6-leaf stage of seedling was superior to that in 4-leaf stage of seedling. A protective effect on Phytophthora blight was displayed by copper hydroxide, sulfur/quicklime, water soluble calcium, phosphorous acid, plant essential oil, and cloves extract. When C. acutatum was inoculated by the non-wound method, copper hydroxide and rapeseed oil showed excellent protective activities with control values of 91.3% and 82.6%, respectively. However, copper hydroxide did not show any activity, when C. acutatum was inoculated after wounding pepper fruits. All organic materials never showed the curative effect on Phytophthora blight and anthracnose in pepper seedling assay and fruit assay.

• Journal of Food Hygiene and Safety
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• v.37 no.6
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• pp.418-428
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• 2022

The purpose of this study was to obtain the codex classification information on the primary food commodity (fresh state) of processed foods of plant origin that are included in the Codex Classification of Foods and Animal Feeds. Furthermore, whether or not the primary food commodity is included in the primary food classification from the Food Code of Korea was investigated. The results are summarized as follows: First, the Codex Classification information (number of classification codes/number of the primary food commodity group that fresh commodities of processed foods are classified/number of primary food commodity that is not included in the Codex Classification) by a processed food group appeared to be 46/8/0 for dried fruits, 76/11/1 for dried vegetables, 54/4/12 for dried herbs, 36/1/0 for cereal grain milling fractions, 17/4/3 for oils and fats (crude), 34/8/9 for oils and fats (refined), 20/8/0 for fruit juices, 3/2/0 for vegetable juices, and 19 codes for teas (in the Codex Classification, the primary food commodity group for tea does not exist). Second, the number of the primary food commodities not included in the Food Code of Korea was 9 for dried fruits, 14 for dried vegetables, 35 for dried herbs, 0 for cereal grain milling fractions, 6 for teas, 3 for oils and fats (crude), 9 for oils and fats (refined), 2 for fruit juices, and 0 for vegetable juices. Third, it was demonstrated that caution should be exercised when using Codex Classification due to differences in food classification between Codex and Korea, such as coconut (Codex, as tree nut as well as assorted tropical and sub-tropical fruit) and olive (Codex, as assorted tropical and sub-tropical fruit as well as olives for oil production), as well as special cases in the Codex Classification, such as dried chili pepper (Codex, as spice), tomato juice (Codex, as vegetable for primary food commodity and as fruit juice for juice) and ginger (Codex, as spice for rhizome and not including as primary commodity for leaves).

• Research in Plant Disease
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• v.24 no.2
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• pp.145-152
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• 2018

During 2015-2017, we surveyed the incidence of viral infections of tomato and paprika growing in greenhouses in Cherwon province, Korea. In 2015 and 2016, we collected leaves and fruits from tomato and paprika plants growing in greenhouses. We detected viruses in the samples collected using specific primer sets for Broad bean wilt virus 2 (BBWV2), Cucumber mosaic virus (CMV), Pepper mild mottle virus (PMMoV), Pepper mottle mosaic virus (PepMoV), and Tomato spotted wilt virus (TSWV). We detected PMMoV, CMV, and TSWV in the samples, and CMV and TSWV were the most prevalent. For the prevention of future viral diseases, we then surveyed the routes of infection by these viruses in tomato and paprika plants growing in greenhouses in Cherwon province in 2017. Leaf and fruit samples were collected from seedlings and crops two and four months after transplanting into greenhouses. As a result, we found that TSWV was transferred from seedlings to plants, and outbreaks of the virus occurred at the early stage of cultivation. On the other hand, we found that CMV was a virus indigenous to the soil of some towns in Cherwon province, and thus outbreaks of this virus occurred at the middle stage of cultivation.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.3
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• pp.205-214
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• 1989

The present experiment was conducted to investigate effects of soil conditioner applied on continuous cropping fields of red pepper from 1985 to 1986 in Imsil, Chunbuk province. 1. The ratios of bacteria/fungi (B/F) and actinomycetes/fungi (A/F) in the soils of continuous cultivation were increased with application of phytotoxin decomposers such as deep tillage (De), compost (Co), magnesium lime (Mg), gypsum silicate, and De + Co + Mg. 2. Degradation of phytotoxin (p-hydrohylenyons aeid) in the continuous soils was promoted with application of De, Co, Mg, gypsum, silicate and De + Co + Mg resulting in yield increase. 3. The infection rate plant by phytophthora were decreased with deep tillage and application of compost and magnesium lime and caused the increase of yield (22%) due to the increase of fruit per hill.