• Korean journal of applied entomology
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• v.19 no.4 s.45
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• pp.228-233
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• 1980

The infection rate of soybean black root rot disease caused by Calonectria crotalariae was about $14\%$. The isolated fungi from the infected soybean roots and stems were Calonectria crotalariae, Fusarium solani, F. roseum, Phomopsis sojae, Pythium aphanidermatum, Rhizoctonia solani and Macrophomina sp. Among them, C. crotalariae was the most virulent pathogen under the laboratory conditions. Mycelial growth and microsclerotial formation were good on PSA containing 1000cc of water, 100g of potato and 20g of sugar. Mycelial growth, sporulation and microsclerotial formation were good on sterilized root. Perithecial formation was better in the dark condition than in the light. Survival of macroconidia was not available between $0\~25\%$ soil water content. Microsclerotia and mycelium in infected plant debris were survived for 4 months at to $8\%\;50\%$ soil water content. The plant height, when inoculated with $1.2\%$ inoculum density, reached approximately half of uninoculated plants. Disease severity was much higher at nonsterilized soil than completely sterilized soil. It was determined that the host range of this pathogen includes soybean, peanut, green bean and red bean.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.4 no.1
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• pp.103-108
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• 1968

Resistance to various diseases of Korean native varieties were investigated in field. The results obtained are summarized as follows: 1) The varieties Ubangtchio and Osib-eubthio were moderately resistant to black shank, but Suantchio, Usultchio and Gwangtchio were slightly resistant. Dixie Bright 101, $H_2$ and Bright Yellow 4 were more resistant to black shank than any of the Korean native varieties. 2) Mokgitchio, Ubangtchio and Osib-eubtchio were moderately resistant to black root rot, but Useultchio Suantchio and Hoetchio were susceptible than Others. 3) Muktchio, Hoetchio and Ubangtchio were slightly resistant to wild fire. 4) Osib-ebthio was highly resistant to brown spot, but Ubangtchio, Hyangtchio and Mokgitchio were moderately resistant and Useultchio was susceptible to brown spot, but it was resistant than Bright ellow 4 or Bernhart 1000-1. 5) Hyangtchio was slightly resistant to CMV-Y. According to these results, except Virus disease, Ubangtchio was resistant to all of the above mentioned diseases. Osib-eubtchio, Hoetchio, Hyangtchio and Suantchio showed proferable disease resistant and these might be well utilized as breeding materials.

• Korean Journal Plant Pathology
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• v.10 no.3
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• pp.175-180
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• 1994

The fungal pathogen Monosporascus annonballus was first isolated in Korea from the rotted roots of bottle gourd stocks of collapsed watermelon plants in fields near Chochiwon, Choongnam province in July, 1993. Perithecia of M. cannonballus were dark brown to black, globose, 220~570 ${\mu}{\textrm}{m}$ in diam. and had many asci. Asci are hyaline, clavate to pyriform, and 50~120$\times$35~570 ${\mu}{\textrm}{m}$ in size. Ascospores were aseptate, dark brown to black, globose, 25~45$\times$30~50 ${\mu}{\textrm}{m}$ in diam, and borne singly in each ascus. The fungus grew in the temperature range of 4 to 34$^{\circ}C$, best at 3$0^{\circ}C$. The optimum pH for growth was 6.8. Mycelial growth rate of M. cannonballus was 25.5mm/day on PDA at 26$^{\circ}C$. Perithecia began to form after 20-day-growth on PDA and produced mature asci after 30 days or later. In the greenhouse inoculation tests, the fungus developed water-soaked lesions on roots of bottle gourd seedlings and was then reisolated from the lesions. Severed damages on watermelon plants by M. cannonballus are greatly concerned in Korea, since no stocks used for watermelon cultivation have reported to be resistant to the fungus.

• Journal of Microbiology and Biotechnology
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• v.22 no.7
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• pp.883-888
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• 2012

The efficacy of cowdung, Bangladesh Institute of Nuclear Agriculture (BINA)-biofertilizer, and Bangladesh Agricultural University (BAU)-biofungicide, alone or in combination, was evaluated for controlling foot rot disease of lentil. The results exhibited that BINA-biofertilizer and BAU-biofungicide (peat soil-based Rhizobium leguminosarum and black gram bran-based Trichoderma harzianum) are compatible and have combined effects in controlling the pathogenic fungi Fusarium oxysporum and Sclerotium rolfsii, which cause the root rot of lentil. Cowdung mixing with soil (at 5 t/ha) during final land preparation and seed coating with BINA-biofertilizer and BAU-biofungicide (at 2.5% of seed weight) before sowing recorded 81.50% field emergence of lentil, which showed up to 19.85% higher field emergence over the control. Post-emergence deaths of plants due to foot rot disease were significantly reduced after combined seed treatment with BINA-biofertilizer and BAU-biofungicide. Among the treatments used, only BAU-biofungicide as the seed treating agent resulted in higher plant stand (84.82%). Use of BINA-biofertilizer and BAU-biofungicide as seed treating biocontrol agents and application of cowdung in the soil as an organic source of nutrient resulted in higher shoot and root lengths, and dry shoot and root weights of lentil. BINA-biofertilizer significantly increased the number of nodules per plant and nodules weight of lentil. Seeds treating with BAU-biofungicide and BINA-biofertilizer and soil amendment with cowdung increased the biomass production of lentil up to 75.56% over the control.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.603-606
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• 2009

Lipoxygenase and Kunitz trypsin inhibitor protein of mature soybean [Glycine max (L.) Merr.] seed are main anti-nutritional factors in soybean seed. A new soybean cultivar, "Gaechuck#1" with the traits of black seed coat, green cotyledon, lipoxygenase2,3 and Kunitz trypsin inhibitor protein free was developed. It was selected from the population derived the cross of "Gyeongsang#1" and C242. Plants of "Gaechuck#1" have a determinate growth habit with purple flowers, brown pubescence, black seed coat, black hilum, oval leaflet shape and brown pods at maturity. Seed protein and oil content on dry weight basis have averaged 39.1% and 16.2%, respectively. It has shown resistant reaction to soybean necrosis, soybean mosaic virus, Cercospora leaf spot and blight, black root rot, pod and stem blight, and soybean pod borer. "Gaechuck#1" matured on 5-10 October with a plant height of 50 cm. The 100-seed weight of "Gaechuck#1" was 23.2g. Yield of "Gaechuck#1" was averaged 2.2 ton/ha from 2005 to 2007.

• Korean Journal of Agricultural Science
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• v.40 no.4
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• pp.325-331
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• 2013

This experiment has been carried out to determine optimal culture conditions for the production of cut flowers and tubers of Calla (Zantedeschia 'Golden Affair' and 'Black Magic') in highlands. Treatments consisted of various levels of root zone environments, Results are as follows: Calla 'Golden Affair' were grown with different mulching materials such as Non-mulching, Black film, reflective film, Rice hull. Mulching materials resulted in no difference in the number of cut flowers but flower length was highest in reflective film. Calla 'Black Magic' were treated with various soil water content, soil type and watering time. Number of cut flowers and flower quality were greatest when the plants were watered at -80 kPa soil water content. No symptoms of soft rot (Erwinia carotovora) was observed at this soil water content. The occurrence of soft rot was observed with similar percentage according to soil type and the soil water content. When Calla 'Black Magic' were watered at the time of soil surface drying, growth was greater compared to others. Air temperature and PPF affected plant growth and photosynthesis. Photosynthetic rate was greatest at $25^{\circ}C$ and PPF $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, while lowest at $28^{\circ}C$ and PPF $800{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. Soft rot did not occur without regard to dipping treatment (0, 5, 10, 24, 48 hours) when the day and night temperature were maintained at $25^{\circ}C$ and $20^{\circ}C$, respectively.

• Korean Journal Plant Pathology
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• v.14 no.5
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• pp.555-557
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• 1998

Occurrence of soft rots was observed on wasabi (Wasabia japonica Matsum) grown in Chuncheon and Pyengchang Kangwon province, Korea. The symptoms appeared on the wasabi root, which became mushy and black. This eventually resulted in wilting and death of the aboveground parts of the wasabi. The causal organism was isolated from the infected lesions and was identified as Erwinia carotovora subsp. carotovora based on the morphological, physiological and biochemical characteristics, and on the results of the Biolog program (Biolog Inc., U. S. A.). E. carotovora subsp. carotovora is the first described bacterium which causes bacterial soft rot on wasabi in Korea.

• The Korean Journal of Community Living Science
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• v.17 no.3
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• pp.89-97
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• 2006

This study was conducted to compare soybean growth and yield and the degree of weed emergence according to no-tillage and conventional tillage system in two different drained paddy fields, loam of Chilgok series and silty clay loam of Deokpyeong series. In both soil conditions, the maturing time of the soybeans by the no-tillage system was two days earlier than that by the conventional tillage system. In the loam of Chilgok series, the stem length of the soybeans in the no-tillage system was 5.7 cm longer than that in the conventional tillage system. The miss-planted rate and diseased plants of black root rot (Calonectria iliacola) in the no-tillage system were 9.2% and 2.8% lower, respectively than those in the conventional tillage system. Also, the nodulation and seed yield in the no-tillage system were 32% and 13% more, respectively, than those in the conventional tillage system. In the silty clay loam of Deokpyeong series, the stem length of the soybeans in the no-tillage system was 4.6cm shorter than in the conventional tillage system. The diseased plants of black root rot (Calonectria iliacola) in the no-tillage system were 4.2% lower than those in the conventional tillage system. Also, no significant difference in the seed yield between the no-tillage and conventional tillage systems was observed. On the other hand, there was a lower occurrence of weed in the no-tillage system than in the conventional tillage system, and the income increased by 19% owing to yield increase and reduced management costs.

• Research in Plant Disease
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• v.11 no.2
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• pp.208-212
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• 2005

At the survey of June, 2002, total 294 dead frees were found in 20 ha of Black pine (Pinus thunbergii) forest located in the western coastal region of Korean peninsula. The dead trees were scattered over the 27 place as groups of about ten trees each. As a result of the field survey on the relationship between the conditions of dead trees and the occurrence of fruiting bodies of Rhizina undulata around the dead and/or dying trees, from June 2002 to August 2004 in the four plots, the occurrence of infected trees was observed as a shape of an irregular concentric circle from the first infected tree and R. undulata was found mainly around the dead tree. Because there was no observation of any other insects and pathogens which would kill trees, the cause of tree death in groups was considered owing to R. undulata. From the analysis of the physical and chemical proper ties of the soil collected from the damaged areas, the pH of soil was between 4.6 and 5.8 and the contents of soil nutrients were very low. Any "fire" trace was not found at all the 27 damaged places in the area, Taean, Chungcheongnam-Do, which are generally known as an important factor to initiate development of the disease. Therefore, further examination is needed to verify precisely about other environmental factors related with the group dying of the Black pines in this area beside 'fire'.

• Current Research on Agriculture and Life Sciences
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• v.17
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• pp.7-13
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• 1999

Thirty bacteria were isolated from the red pepper rhizosphere. The isolates were screened for antagonism to Alternaria alteranta causing red pepper black rot. Antagonistic bacterium No. J-24 was selected among the isolated bacteria and was identified as Bacillus subtilis based on morphological and physiological characteristics and MIDI system. B. subtilis J-24 showed antifungal activities against A. alternata(inhibition percentage, 99%), Botrytis cinerea, Phytophthora capsici, Pythium ultimum, Colletotrichum gloeosporioides, Stemphylium botryosum. The growth of red pepper seedling was promoted as compared to control when the microbial inoculants was mixed in bed soil. In the mixed microbial inoculants bed soil, the leaf area of red pepper was increased of 15 percent, the hypocotyl weight 12 percent, the root length 12 percent, total dry weight 13 percent as compared to those grown in the general bed soil.