• 한국균학회소식:학술대회논문집
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• 2016.05a
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• pp.25-25
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• 2016

Biological control has many advantages as a disease control method, particularly when compared with pesticides. One of the most important benefits is that biological control is an environmental friendly method and does not introduce pollutants into the environment. Another great advantage of this method is its selectivity. Selectivity is the important factor regarding the balance of agricultural ecosystems because a great damage to non target species can lead to the restriction of natural enemies' populations. The objective of this research was to evaluate the effects of several different bacterial isolates on the efficacy of biological control of soil borne diseases. White rot caused by Sclerotium cepivorum was reported to be severe disease of garlic and chive. The antifungal bacteria Burkholderia pyrrocinia CAB08106-4 was tested in field bioassays for its ability to suppress white rot disease. In field tests, B. pyrrocinia CAB08106-4 isolates suppressed white rot in garlic and chive, with the average control efficacies of 69.6% and 58.9%, respectively. In addition, when a culture filtrate of B. pyrrocinia CAB08106-4 was sprayed onto wounded garlic bulbs after inoculation with a Penicillium hirstum spore suspension in a cold storage room ($-2^{\circ}C$), blue mold disease on garlic bulbs was suppressed, with a control efficacy of 79.2%. These results suggested that B. pyrrocinia CAB08106-4 isolates could be used as effective biological control agents against both soil-borne and post-harvest diseases of Liliaceae. Chinese cabbage clubroot caused by Plasmodiophora brassicae was found to be highly virulent in Chinese cabbage, turnips, and cabbage. In this study, the endophytic bacterium Flavobacterium hercynium EPB-C313, which was isolated from Chinese cabbage tissues, was investigated for its antimicrobial activity by inactivating resting spores and its control effects on clubroot disease using bioassays. The bacterial cells, culture solutions, and culture filtrates of F. hercynium EPB-C313 inactivated the resting spores of P. brassicae, with the control efficacies of 90.4%, 36.8%, and 26.0%, respectively. Complex treatments greatly enhanced the control efficacy by 63.7% in a field of 50% diseased plants by incorporating pellets containing organic matter and F. hercynium EPB-C313 in soil, drenching seedlings with a culture solution of F. hercynium EPB-C313, and drenching soil for 10 days after planting. Soft rot caused by Pectobacterium carotovorum subsp. carotovorum was reported to be severe disease to Chinese cabbage in spring seasons. The antifungal bacterium, Bacillus sp. CAB12243-2 suppresses the soft rot disease on Chinese cabbage with 73.0% control efficacy in greenhouse assay. This isolate will increase the utilization of rhizobacteria species as biocontrol agents against soft rot disease of vegetable crops. Sclerotinia rot caused by Sclerotinia sclerotiorum has been reported on lettuce during winter. An antifungal isolate of Pseudomonas corrugata CAB07024-3 was tested in field bioassays for its ability to suppress scleritinia rot. This antagonistic microorganism showed four-year average effects of 63.1% of the control in the same field. Furthermore, P. corrugata CAB07024-3 has a wide antifungal spectrum against plant pathogens, including Sclerotinia sclerotiorum, Sclerotium cepivorum, Botrytis cinerea, Colletotrichum gloeosporioides, Phytophotra capsici, and Pythium myriotylum.

• Horticultural Science & Technology
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• v.18 no.3
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• pp.348-352
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• 2000

Four different Chinese cabbage cultivars were compared for their physicochemical quality characteristics including crude fiber, chlorophyll, firmness, hardness, sugar, and flavor at different parts of the cabbages. No significant difference in crude fiber content was observed among cultivars. Chlorophyll content in midrib was not significantly different among cultivars, however Chlorophyll content in leaf of 'Golden House' and 'Golden Spring' were greater than that of 'Alpine Summer' Firmness was the highest in 'Golden House' and 'Golden Spring' but hardness was not significantly different among cultivars. Sugar content was higher in midrib than in leaf. 'Golden Spring' a showed the highest sugar content in midrib. Glucose content was higher than the fructose content in leaf, but was opposite in midrib. Sensory evaluation showed that 'Golden House' and 'Golden Spring' were the best in yellowness, and 'Golden House' and 'Alpine Summer' were the best for their taste and aroma in midrib, however, no significant difference in texture was observed among cultivars.

• Journal of Bio-Environment Control
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• v.21 no.3
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• pp.271-275
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• 2012

The average annual and winter ambient air temperatures in Korea have risen by $0.7^{\circ}C$ and $1.4^{\circ}C$, respectively, during the last 30 years. The continuous rise in temperature presents a challenge in growing certain horticultural crops. Chinese cabbage, one most important cool season crop, may well be used as a model to study the influence of climate 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 Chinese cabbage cultivar (Chunkwang) during the spring growing season to estimate crop yield under the unfavorable environmental conditions. The chinese cabbage plants were transplanted from Apr. 8 to May 13, 2011 when 3~4 leaves were occurred, at internals of 7 days and cultivated with 3 levels of nitrogen fertilization. The data from plants transplanted on Apr. 22 and 29, 2012 were used for the prediction of yield as affected by planting date and nitrogen fertilization for spring production. In our study, plant dry weight was higher when the seedlings were transplanted on 15th (168 g) than on 22nd (139 g) of April. There was no significant difference in the yield when plants were grown with different levels of nitrogen fertilizer. The values of correlation coefficient ($R^2$) between GDD and number of leaves, and between GDD and dry weight of the above-ground plant parts were 0.9818 and 0.9584, respectively. Nitrogen fertilizer did not provide a good correlation with the plant growth. Results of this study suggest that the GDD values can be used as a good indicator in predicting the top biomass yield of Chinese cabbage.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.5
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• pp.274-280
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• 2005

Enormous amount of oyster-shell waste has been illegally disposed at oyster farm sites along the southern coast of Korea and then made a serious problem in environmental side. To increase the consumption of oyster shell meal as a soil amendment, the effects of oyster shell meal on soil properties and spring Chinese cabbage productivity were evaluated in silt loam soil to which 0, 4, 8, 12 and $16Mg\;ha^{-1}$ of oyster-shell meal fertilizer were added. Hydrated lime treatment ($2Mg\;ha^{-1}$) was selected as a control. Oyster-shell meal fertilizer, which made by a simple crushing and has high alkalinity as a calcium materials, had significant effects on neutralizing acid soil and on supplying calcium element. Spring Chinese cabbage yields increased with shell meal application. Plant uptakes of macro-nutrients such as P and C, and micro-nutrient such as B were significantly increased by oyster-shell meal application and then contributed to promote Chinese cabbage growth. The highest yield was achieved following the addition of $8Mg\;ha^{-1}$ shell meal application, and the same yield with that in lime treatment was at the $4Mg\;ha^{-1}$. Oyster-shell meal had more substantial effect on suppling calcium and on improving soil pH than that of lime. In conclusion, oyster shell meal fertilizer could be a good supplement to other inorganic soil amendments to improve nutrient balances in upland soils.

• Korean journal of applied entomology
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• v.25 no.3 s.68
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• pp.129-132
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• 1986

Colonizing aphid species on Chinese cabbage, radish, red pepper and cucumber and their seasonal fluctuations were investigated without insecticide treatment during $1982{\sim}1984$ at an experimental farm in Suweon. The major species among the colonizing aphids in each crops were Myzus persicae (Sulzer) and Lipaphis erysimi (Kaltenbach) on Chinese cabbage and radish; M. persicae (Sulzer) and Aphis gossipii Glaver on red pepper; and A. gossipii Glover on cucumber, respectively. Over 200mm of rainfalls within a 10-day period reduced the aphid populations drastically. Relative abundance of the two major aphids on Chinese cabbage and radish, and on red pepper showed inverse relationships between the spring and autumn densities within the same year.

• Korean Journal of Organic Agriculture
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• v.26 no.1
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• pp.129-140
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• 2018

Pectobacterium carotovorum subsp. carotovorum was found to be highly virulent to various vegetables, including Chinese cabbage. The antibacterial isolate CAB12243-2 was tested in a field bioassay for suppressing soft rot disease. The nucleotide sequencing of the 16S rRNA gene identified, the CAB12243-2 strain used in this study as Bacillus toyonensis. B. toyonensis CAB12243-2 inhibited the pectate lyase process by soft rot pathogens, and used trehalose and glucose as carbon sources. In field tests, the antibacterial isolate B. toyonensis CAB12243-2 suppressed soft rot disease with 73.0% control efficacy on the spring cultivar "Norangbom" and with 68.9% efficacy on the fall cultivar "Bulam 3". These results suggest that B. toyonensis CAB12243-2 can be used as a biological control agent for the control of soft rot diseases on vegetables.

• The Korean Journal of Food And Nutrition
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• v.30 no.5
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• pp.1007-1014
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• 2017

To compare functional Chinese cabbage('Amtak' baechu; F1 hybrid cultivar between Brassica rapa and B. perkinensis, AB) with general Chinese cabbage ('Chunkwang' baechu; general spring cultivar, CB), two kinds of kimchi(ABK and CBK) prepared with AB and CB cultivar were fermented at $10^{\circ}C$ for 10 days. Their fermentative characteristics and anti-proliferative activities against mouse carcinoma cell lines were investigated. General kimchi(CBK) showed mature pH on the $6^{th}$ day of fermentation, whereas functional kimchi(ABK) reached pH on the $9^{th}$ day. CBK also exhibited acidity of mature stage on the $6^{th}$ day, but ABK reached mature acidity on the $9^{th}$ day. Although ABK and CBK were salted in the same condition, ABK had lower salinity than CBK, throughout the fermentation time. The highest total bacterial and lactic bacterial counts of CBK showed on the $8^{th}$ day of fermentation, but ABK showed the highest total bacterial and lactic bacterial counts on the $10^{th}$ day. The texture of ABK was harder than CBK for fermentation time. This seems to be corrleated with the slower fermentation rate of ABK. ABK showed significantly higher anti-proliferative activity (54.6% cell viability of control) in B16BL6 at $1,000{\mu}g/mL$. ABK was also higher in anti-proliferative activity than CBK throughout the fermentation time. However, there was no significant difference in the anti-proliferative activity of ABK between the fermentation times. In conclusion, fermentation of ABK showed a better texture, due to the slow fermentation rate and more anti-proliferative activity against mouse carcinoma cell line than those of CBK.

• Weed & Turfgrass Science
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• v.3 no.3
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• pp.215-220
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• 2014

This study was conducted to evaluate potential weed control in organic farming field using false seedbed and stale seedbed techniques. The experiment was conducted in open upland fields during spring and fall crop seasons. The false seedbed was prepared before 2-4 weeks of crop culture and was treated with shallow tillage or flame weeding before transplanting. The weed suppression rates of false seedbed treatment in the spring crop experiments for Chinese cabbage, soybean, hot pepper and corn were 65-73%, 50-55%, 9-55% and 8-33%, respectively. According to crop growth and yield in this experiment, the false seedbed technique has some potential weed control for Chinese cabbage, soybean and corn. The weed suppression rates of stale seedbed treatments in the fall crop experiments for Chinese cabbage, spinach and carrot were 18-39%, 40-77% and 37-38%, respectively. Weed control efficacy of the stale seedbed in this study was lower, when compared with false seedbed.

• Journal of Bio-Environment Control
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• v.20 no.4
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• pp.326-332
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• 2011

The growth and bolting characteristics of spring Chinese cabbage cultivars at two night-time temperature treatments such as $5^{\circ}C$ and $10^{\circ}C$ during seedling stage were investigated to establish a safe environmental management strategy for raising seedlings. The low night-time temperature treatments were applied at 5, 10, and 15 days after sawing and the treatment durations were 5, 10, and 15 days in each of treatment beginning. The growth of seedlings in all the tested cultivars were linearly reduced as the treatment duration was extended and no symptoms of bolting were found. The reduction rate in seedling growth of 'Chunkwang' reached to 59.3% at most by 15 days of $5^{\circ}C$ treatment when it be compared to that of control. However, no symptoms of bolting were shown in the treatments of two night-time temperatures until the harvest at 90 days after sawing, indicating that the vernalization effect by low night-time temperature could be mitigated by subsequent day-time optimal temperature management. This study showed that the major spring Chinese cabbage cultivars require more ultimate level of low night-time temperature treatment for the vernalization than this study. It is also supposed that the optimal day-time temperature management can reduce or delay the rate of bolting, even if the seedlings were exposed to short-term low temperature below $5^{\circ}C$ during night-time.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1239-1244
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• 2011

Importance of climate change and its impact on agriculture and environment has increased with a rise of greenhouse gases (GHGs) concentration in Earth's atmosphere. Nitrous oxide ($N_2O$) emission in upland fields were assessed in terms of emissions and their control at the experimental plots of National Academy of Agricultural Science (NAAS), Rural Development Administration (RDA) located in Suwon city. It was evaluated $N_2O$ emissions with different growing periods (spring and autumn seasons), tillage and no tillage conditions in a chinese cabbage field. The results were as follows: 1) An amount of $N_2O$ emissions were high in the order of Swine manure compost>NPK>Hairy vetch+N fertilizer. By tillage and no tillage conditions, $N_2O$ emissions were reduced to 33.7~51.8% (spring season) and 31.4~76.7% (autumn season) in no-tillage than tillage conditions. 2) In autumn season than those spring season, $N_2O$ emissions at NPK, hairy vetch+N fertilizer and swine manure compost were reduced to 49.6%, 39.0% and 60.0%, respectively, in tillage treatment and 59.5%, 70.6% and 58.7%, respectively, in no-tillage treatment. 3) $N_2O$ emission measured in this study was 15.2~86.4% lower with tillage and no tillage treatments than that of the IPCC default value (0.0125 kg $N_2O$-N/kg N).