• Research in Plant Disease
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• v.13 no.3
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• pp.157-163
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• 2007

Hot water treatment that is the most appropriate seed disinfection method for organic vegetable farming was evaluated in this study. Among the leafy vegetable seeds lettuce that was the most sensitive to hot water was suitable to treat at $45^{\circ}C$ for 25 min, while Chinese cabbage and radish seeds were optimally treated at $50^{\circ}C$ for 25 min. The treatments resulted in similar or higher seed germination rate than non-treated seeds and promoted plant growth. In addition, fungi such as Alternaria, Aspergillus, Penicillium, or Mucor grown on the seeds were suppressed over 90% and the bacterial growth on lettuce seeds reduced 98.5% by the treatment. Among the fruit vegetable seeds pumpkin that was vulnerable to hot water was suitable to treat at $50^{\circ}C$ for 15 min, while cucumber and hot pepper seeds revealed optimum treatment at $50^{\circ}C$ for 25 min as chinese cabbage and radish. The treatment also showed similar or higher seed germination rate and growth than non-treated seeds. Furthermore, fungi such as Rhizopus, Aspergillus, Penicillium or Mucor grown on the seeds reduced from 72.0% to 95.4%. The bacterial growth on cucumber and red pepper seeds was suppressed from 65.5% to 86.0% by the treatment. Results indicated that the hot water treatment is practical for disinfection of organic vegetable seeds and the optimum temperature and soaking time varied among the seeds.

• 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.

• Horticultural Science & Technology
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• v.18 no.2
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• pp.93-97
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• 2000

This study was conducted to determine the appropriate osmotic priming chemicals and their concentrations to improve germination of carrot, lettuce, onion, and Welsh onion seeds. Each chemical, including $KNO_3$, $KH_2PO_4$, $K_3PO_4$, NaOH, $Ca(NO_3)_2$, and PEG 8000, was tested at three to four concentrations. Percent germination, number of days to attain 50% of the final germination percentage (T50), and mean number of days to germination (MDG) of primed seeds were compared with those of water-imbibed or nonprimed seeds. With the exception of 100 or 200 mM NaOH, other priming chemicals did not affect percent germination of carrot and lettuce seeds. However, the chemical priming did reduce T50 and MDG, especially with -0.5 MPa PEG 8000 for carrot and with 50 mM $K_3PO_4$ or 200 mM $KH_2PO_4$ for lettuce. Among the chemicals with no influence on percent germination did 200 mM $KH_2PO_4$ significantly reduced both T50 and MDG of onion seeds. No chemicals improved percent germination of Welsh onion seeds. Reduction in T50 and MDG was significant only with $KH_2PO_4$ and $Ca(NO_3)_2$.

• Korean Journal of Plant Resources
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• v.19 no.1
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• pp.169-173
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• 2006

The effects of aqueous extract and volatile substances of 2 Angelica plants on seed germination and seedling growth were investigated. The seed germination of Angelica gigas showed increase in proportion to increase in aqueous extract concentration of A. gigas, while that of Angelica acutiloba was reduced proportionally to the extract concentration. The seed germination of A. gigas and A. acutiloba treated with aqueous extract of A. acutiloba was inhibited. The seedling elongation of A. gigas and A. acutiloba was slightly increased at lower concentration of aqueous extract of A. gigas, whereas it was proportionally decreased at higher concentrations. The seedling elongation of 2 Angelica plants was decreased by the aqueous extract of A. acutiloba. The aqueous extract of A. acutiloba caused significant inhibition in seedling growth of 2 Angelica plants. The seed germination of Lactuca sativa was not affected by volatile substances emitted from 2 Angelica plants. The radicle elongation of L. sativa treated with volatile substances of 2 Angelica plants was inhibited slightly and it was not suppressed according to the concentration of volatile substances.

• Journal of Life Science
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• v.23 no.12
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• pp.1415-1419
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• 2013

Electron beam (EB) irradiation was tested to determine the dose required to eradicate plant pathogens, such as Botrytis cinerea and Agrobacterium rhizogenes, from the infected seeds without affecting the germination rate of the irradiated vegetable seeds, including crown daisy, cucumber, hot pepper, green onion, leaf lettuce, and radish seeds. EB irradiation of 1.5 kGy and 2 kGy was sufficient to kill 100% of hairy root disease bacteria and gray mold conidia, respectively. EB irradiation showed no effect or minimal effect on the germination rate of the crown daisy, cucumber, green onion, and radish seeds. However, the germination rate of the hot pepper and leaf lettuce seeds was significantly reduced by using 2 kGy of EB irradiation. Difference in susceptibility to EB irradiation appears not to be related to the weight of each seed, but to the intrinsic characteristic of each plant. Conclusively, EB irradiation might be a useful way to decontaminate crown daisy, cucumber, green onion, and radish seeds.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2003.02a
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• pp.440-445
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• 2003

식물의 공장적 생산에 있어서 재배적인 측면에서 중요한 요소 중의 하나는 환경조절과 양액제어 그리고 종자발아기술, 녹화기술일 것이다. 그 중에서도 종자를 파종한 후의 발아기간이 일정하지 않거나 조절이 어려우면 엽채류의 공장적 생산에서 중요한 매일 정식, 매일 수확이 어렵게 된다. 일반적으로 상추의 발아적온은 18-$25^{\circ}C$이다. 그러나 작물생육에 중점을 두어 환경을 조절하는 현재의 제어온실내에서는 발아적온을 맞추기가 어렵다. 따라서 별도의 발아장치가 필요하다. (중략)

• Proceedings of the Korean Society of Crop Science Conference
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• 1994.06a
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• pp.100-101
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• 1994

• Proceedings of the Korean Society of Life Science Conference
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• 2003.05a
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• pp.69-70
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• 2003

• Proceedings of the Korean Society of Life Science Conference
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• 2003.05a
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• pp.71-72
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• 2003

• Korean Journal of Organic Agriculture
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• v.13 no.3
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• pp.291-300
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• 2005

Diseases were surveyed in 5 Rice paddy field areas of Organic paddy field and conventional paddy field. The 3 major diseases, rice leaf blast, bacterial leaf blight and sheath blight in rice were surveyed at duck raising, rice bran and conventional rice paddy field. They were serious in duck raising paddy field, rice bran paddy field more than conventional paddy field. The Ilpum variety were infected seriously more than Chucheong. At the effectivity test of the environment-friendly substance for the rice-seed sterilization, 1000-times diluted brown-rice vinegar showed controlling effect against Bakanae disease, and germination rate also was good. There was no Weeds Control efficacy by cultivating of hairy vetch in rice paddy field. However, extract of hairy vetch Leaf and root repressed the germinating of lettuce seed.