• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2007.11a
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• pp.213.2-213.2
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• 2007

• Food Science and Preservation
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• v.16 no.6
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• pp.971-976
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• 2009

The consumption of raw sprouts has increased in popularity worldwide because the food is natural and healthy. However, in Korea, nothing is known on the safety standards of sprout producers or changes in the microbial populations of sprouts during sprouting. We evaluated the microbial safety and quality of sprouts during each step in the sprouting process. Bacteriological analysis showed that seeds had a Total Plate Count (TPC) ranging from 3.04 - 5.21 log CFU/g and coliform counts ranging from 1.80 - 3.86 log CFU/g. TPC and coliform counts increased rapidly during the sprouting process to attain values of 6.99 - 8.26 and 3.70 - 7.15 log CFU/g, respectively, regardless of decontamination of seeds with commercial sanitizer. TPC and coliform counts were on high level after sprouts were washed. Escherichia coli was detected in samples of domestic radish sprouts at all stages from seed to storage, rape sprouts in the stages from soaked seed to storage, and red radish sprouts during sprouting, and no sanitizer was used in any of these processes. Untreated red radish sprouts were also positive for Bacillus cereus at all processing steps and Listeria monocytogenes after germination. However, pathogens were not detected at any sprouting stage of seeds treated with sanitizer. It is necessary to carefully control commercial sprouting, and to develop HACCP guidelines applicable to all sprouting processes, commencing at the first step in raw seed production.

• Korean Journal of Agricultural Science
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• v.49 no.3
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• pp.655-666
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• 2022

We assessed the persistence of eight major cruciferous crops-leaf mustard, oilseed rape, cabbage, broccoli, cauliflower, Chinese cabbage, turnip, and radish-growing in the field. In the first part of our experiment, we tested the viability of seeds that had been buried at two different soil depths for up to 16 months. We then broadcast seeds over the soil surface and left them undisturbed to investigate the survivorship of the resultant plants over two years. Seed viability was significantly affected by plant taxa and burial depth, but not substantially affected by the duration of burial. Although seeds of leaf mustard had the greatest viability among all crops examined here, the viability rates were significantly lower at 2 cm depth than at 15 cm. Seeds of leaf mustard, oilseed rape, broccoli, turnip, and Chinese cabbage remained viable throughout the 16-month period. A study of plant demography revealed that only leaf mustard and oilseed rape succeeded in producing seeds and overwintering in the undisturbed field. However, neither of those species competed well with other plants long-term and their overall growth and survival rates declined during the evaluation period. In addition, insect herbivory severely decreased the growth of all of these crops. Our results suggest that populations of leaf mustard and oilseed rape do not tend to persist in the field for more than a few years without disturbance and external seed inputs.

• Research in Plant Disease
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• v.17 no.1
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• pp.52-58
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• 2011

The aim of this research was to develop specific and sensitive PCR-based procedures for simultaneous detection of economically important plant pathogenic bacteria and seed borne virus in commercial Brassicaceae crop seeds, Xanthomonns campestris pv. campestris (Xcc) and Lettuce Mosaic Virus (LMV). Bacterial and virus diseases of Brassicaceae leaves are responsible for heavy losses. PCR with arbitral primers: selection of specific primers, performance of PCR with specific primers and determination of the threshold level for pathogens detection. To detect simultaneously the Xcc and LMV in commercial Brassicaceae crop seeds (lettuce, kohlrabi, radish, chinese cabbage and cabbage), two pairs of specific primer (LMV-F/R, Xcc-F/R) were synthesized by using primer-blast program (http://www.ncbi.nlm.nih.gov/tools/primer-blast/). The multiplex PCR for the two pathogens in Brassicaceae crop seeds could detect specifically without interference among primers and/or cDNA of other plant pathogens. The pathogen detection limit was determined at 1 ng of RNA extracted from pathogens. In the total PCR results for pathogen detection using commercial kohlrabi (10 varieties), lettuce (50 varieties), radish (20 varieties), chinese cabbage (20 varieties) and cabbage (20 varieties), LMV and Xcc were detected from 39 and 2 varieties, respectively. In the PCR result of lettuce, LMV and Xcc were simultaneously detected in 8 varieties.

• Korean Journal of Food Science and Technology
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• v.43 no.5
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• pp.611-617
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• 2011

This study investigated the germination and reduction of microbial population in domestic (radish, Chinese cabbage, and vitamin) and imported (radish and red cabbage) sprout seeds by heat treatment (40, 50, 60, and 70$^{\circ}C$ for 15 min or 30 min). The germination ratio (define the ratio) was 45-97% at 24 h after treatment <60$^{\circ}C$ and was decreased at 70$^{\circ}C$. In domestic radish seed, total aerobic bacteria were decrease by approximately 1.71 log CFU/g after heat treatment at 70$^{\circ}C$ for 30 min and viable coliforms were decreased to under the detection limit at temperatures over 60$^{\circ}C$. Decrease of total aerobic bacteria and coliforms in domestic Chinese cabbage seed was 1.23-1.34 and 2.77 log CFU/g, respectively, after heat treatment over 60$^{\circ}C$. In domestic vitamin seed, total aerobic bacteria were decreased by about 0.3 log CFU/g at 70$^{\circ}C$ for 15 min. In imported radish seed, total aerobic bacteria were decreased 2.12-2.30 log CFU/g after heat treatment over 60$^{\circ}C$. Total aerobic bacteria in imported red cabbage seed were reduced by 0.66-0.84 log CFU/g after heat treatment over 40$^{\circ}C$ and coliforms were undetectable. In case of Bacillus cereus, there was no significant difference by heat treatment in any sample. Staphylococcus aureus and Salmonella sp. were not detected at the detection limit in any tested seeds at any temperature.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.783-789
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• 1997

This study was conducted to identify leakage of fluorescent substances out of 56 crops and to develop sorting methods of nonviable seeds of Chinese cabbage. Fluorescent substances were detected from 36 species, Chinese cabbage, radish, broccoli, cauliflower, egg plant and rape seed etc. In Chinese cabbage, the germination rate of non-sorted seeds decreased rapidly with ageing of seeds at 45$^{\circ}C$ and 100％. After Chinese cabbage seeds soaked for 4hrs and coated with cellulose, the sorting ratio of non fluorescent seeds were decreased 91.3％ to 1.7％ by increasing ageing periods from control to 8 days, while fluorescent seeds were increased drastically from 8.7％ to 98.3％. Also, incubation of water soaked dead seeds of Chinese cabbage treated with 0.5-1.0％ ninhydrin and 0.01N sodium thiosulfate for 30~60 minutes at 35$^{\circ}C$ developed purple color.

• Journal of Biosystems Engineering
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• v.25 no.6
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• pp.463-470
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• 2000

For maximum seeding efficiency of a nozzle type seeder, the performance of the nozzle should be considered sufficiently. This study was carried out to investigate the optimum operating conditions of a seeder attached the vacuum nozzle which was modified syringe needle acting on the plug seedling tray and the seed plate. Such operating factors as the hole diameter of the nozzle (d), the distance from the nozzle tip to the bottom plate of seed hopper(D) the absorbing air pressure of the nozzle tip(P) the bounding height of seed from the vibrated bottom plate of seed hopper and the seeding speed were selected based on the weight of a grain of seed(W). The treated materials were pepper seed as the flat type, cucumber seed as the oval type and radish seed as the spherical type. The optimum operating conditions of the experimental seeder were revealed as follows: 1. The height of the seed bounding from the bottom plate of seed hopper and the distance from nozzle tip to bounded seed were 5 mm and 0.5 mm at all seeds. The hole diameter of the nozzle and the absorbing pressure for pepper seed, cucumber seed and radish seed was 0.45 mm, 0.65 mm. 0.65mm and 39.2 kPa, 88.3 kPa, 58.8 kPa, respectively. 2. The absorbing pressure P was represented as P=η.4W/$\pi$d$^2$ where η was 100. The seeding speed using a 128 cell tray was 2.4 cm/s which was same transfer as 2.5 trays per minute. 3. The maximum seeding rate in case of the pepper seed was 97% the cucumber seed was 95% and the radish seed was 100% under the optimum operating conditions of the seeder.

• Korean Journal of Environmental Agriculture
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• v.22 no.3
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• pp.215-219
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• 2003

To investigate the effects of low dose gamma radiation and seed moisture content (SMC) on germination and early growth of vegetable crops, seeds of chinese cabbage (Brassica campestris L.), radish (Raphanus sativus L.), red pepper (Capcicum annuum L.), figleaf gourd (Cucurbita ficifolia Bouche) and bottle gourd (Lagenaria siceraria Standl), with different SMC were irradiated with different doses ($0{\sim}20\;Gy$) of gamma-ray by irradiator ($^{60}Co$, ca.150 TBq of capacity, AECL). Vegetable crops in which low dose gamma radiation was irradiated in seeds with different moisture content showed different response in seed germination and early growth to low dose gamma radiation. The germination rate of chinese cabbage, figleaf ground and bottle gourd irradiated with $2{\sim}8\;Gy$ showed interactive responses against relative SMC. Also, significant interactions occurred for the early growth between those factors. The stimulating effects of gamma radiation were more pronounced for hydrated seeds of chinese cabbage, radish, figleaf gourd and bottle gourd showing prominent responses with $2{\sim}10\;Gy$ irradiation, particularly for chinese cabbage and bottle gourd. These results suggest that radiation may promote germination and early growth of vegetable crops through interaction with SMC.

• Korean Journal of Environmental Agriculture
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• v.34 no.3
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• pp.204-209
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• 2015

BACKGROUND: Radish (Raphanus sativus L.) is cultivated worldwide and one of important vegetables in Korea where year-round production of radish is possible. Most of radishes in autumn are cultivated with double-row spacing except for Gangwon-do where sing-row spacing is predominant. However, no research has been conducted on double-row spacing in radish cultivation so far. This study was conducted to reveal the optimum double-row spacing in autumn cultivation of radish. METHODS AND RESULTS: Using top two popular autumn radish cultivars 'S' and 'C', seeds were sown in spacing between rows of $55{\times}25$, $45{\times}25$, $35{\times}25$ and $25{\times}25cm$, and that within rows of $35{\times}28$, $35{\times}25$, $35{\times}22$ and $35{\times}19cm$. Plants were harvested 58 days after sowing and leaf weight, length and number, and root weight, length sugar content and pithiness were investigated. In the spacing between rows, no significant difference was observed in leaf weight, length and number in both cultivars; however, 25 cm of spacing between rows significantly reduced the root length and weight in 'S' and 'C' cultivars, respectively. In spacing within rows, 28, 25 and 22 cm did not affect fresh root weight in both cultivars, producing appropriate radish roots of 1,500g on average. However, 19 cm of spacing within rows did not reduced fresh root weight in 'S' cultivar but did significantly in 'C' cultivar (1148.3 g). Sugar contents and pithiness of roots were also affected by spacing but its effect was very small and different between cultivars. CONCLUSION: It is suggested that optimum double-row spacing in autumn radish cultivation is 35 cm and 22 cm of spacing between and within rows, respectively, the spacing that did not reduce the yield and quality of radish roots in two popular autumn radish cultivars.

• Horticultural Science & Technology
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• v.31 no.5
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• pp.531-537
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• 2013

The average annual and winter ambient air temperatures in Korea have risen by 0.7 and $1.4^{\circ}C$, respectively, during the last 30 years. Radish (Raphanus sativus), one of the most important cool season crops, may well be used as a model to study the influence of climatic change on plant growth, because it is more adversely affected by elevated temperatures than warm season crops. This study examined the influence of transplanting time, nitrogen fertilizer level, and climate parameters, including air temperature and growing degree days (GDD), on the performance of a radish cultivar 'Mansahyungtong' to estimate crop growth during the spring growing season. The radish seeds were sown from April 24 to May 22, 2012, at internals of 14 days and cultivated with 3 levels of nitrogen fertilization. The data from plants sown on April 24 and May 8, 2012 were used for the prediction of plant growth as affected by planting date and nitrogen fertilization for spring production. In our study, plant fresh weight was higher when the radish seeds were sown on $24^{th}$ of April than on $8^{th}$ and $22^{nd}$ of May. The growth model was described as a logarithmic function using GDD according to the nitrogen fertilization levels: for 0.5N, root dry matter = 84.66/(1+exp (-(GDD - 790.7)/122.3)) ($r^2$ = 0.92), for 1.0N, root dry matter = 100.6/(1 + exp (-(GDD - 824.8)/112.8)) ($r^2$ = 0.92), and for 2.0N, root dry matter = 117.7/(1+exp (-(GDD - 877.7)/148.5)) ($r^2$ = 0.94). Although the model slightly tended to overestimate the dry mass per plant, the estimated and observed root dry matter and top dry matter data showed a reasonable good fit with 1.12 ($R^2$ = 0.979) and 1.05 ($R^2$ = 0.991), respectively. Results of this study suggest that the GDD values can be used as a good indicator in predicting the root growth of radish.