• Korean Journal of Microbiology
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• v.4 no.2
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• pp.19-21
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• 1966

For the purpose of determining possibility of aphid-transmission of mosaic disease of black locust, cowpea aphid (Aphis medicagnis Koch) and green peach aphid (Myzus persicae Sulzer) were experimented using cowpea as test plant, and both proved to be the vectors. As for transmission threshold period of cowpea aphid to the virus, the acquisition feeding period was five seconds and inoculation feeding period was two minutes. This black locust mosaic virus, therefore, is a nonpersistent virus.

• Proceedings of the Korean Society of Crop Science Conference
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• 2023.04a
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• pp.142-142
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• 2023

Cowpea(Vigna unguiculata L. Walp) has excellent physical properties and texture of starch, so it is mainly used in various ways for songpyeon sediment, rice-cake paste, and porridge. To utilize it as various processed products such as songpyeon sediment and cowpea milk, 'Okhyun', which has green cotyledons and black seed coats and can be harvested by combine was developed. A cowpea variety 'Okhyun' was improved from the cross between IT145379 and IT208081 at the JARES in 2022. 'Okhyun' has an erect plant with an intermediate plant habit, a light purple-colored corolla, and heart-shaped leaflets. 'Okhyun' has green cotyledons and black seed coats, and has straight black brown pods when mature. The stem length of 'Okhyun' is 47cm, and the weight of 100-seed weight was 12.9g, which was lower than the control variety 'Okdang'(16.6g). 'Okhyun' contains 25.8mg/100g of anthocyanin, 279mg/100g of total polyphenols, and 335mg/100g of total flavonoids, respectively. The average yield of 'Okhyun' was 1.97ton per hectare, 11% higher than that of the control cultivar 'Okdang'. 'Okhyun'' does not require the installation of an espalier-net net, so it is possible to harvest with a combine. In addition, 'Okhyun' variety with green cotyledons and a black seed coat is expected to contribute to developing regional specialties and various processed products.

• Korean Journal of Microbiology
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• v.3 no.2
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• pp.22-26
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• 1965

In order to investigate the host range of the mosaic disease of black locust in the Chunchon area, the sap of the mosaic-diseased leaves of black locust itself and the cowpea leaves infected with the above mentioned sap, were inoculated to 53 species of plants belong to 12 families. As to the result, no difference in infection was found as related to the virus sources, and the infection was recognized in 4 species of the family Chenopodiaceae and 8 species of the family Leguminosae. The plants recognized as hosts are as follows: the plants which showed local infection are Chenopodium album, Ch. ambrosioides, Ch. quinoa; the plants which showed systemic infection are Chenopodium amaranticolor, Phaseolus vulgaris, Robinia pseudo-acacia, Vigna sinensis; and Astragalus sinicus, Melilotus indicus, Phaseolus angularis, Pisum sativum and Vicia faba were recognized as carriers. Through investigating its host ranges and symptoms, this mosaic virus of black locust seems not to be regarded as the group of the black locust mosaic virus in southeastern Europe reported by Milinko et al (1961). And, too, it is thought hardly to exist in combination with the cowpea mosaic virus. It appears, therefore, that this mosaic virus was confined to that of black locust.

• The Plant Pathology Journal
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• v.17 no.6
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• pp.354-356
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• 2001

In August 2001, pod rot of cowpea caused by Choanephora cucurbitarum was found in the experimental fields of the Gyeongsangnam-do Agricultural Research and Extension Services, Korea. Initial symptoms of the disease were the appearance of water-soaked, dark-green lesions and followed by rapid rotting of the infected tissues. As the disease progressed, whitish mycelia and monosporous sporangiophore with monosporous sporangiola were produced on the lesions. The fungus produced white to pale yellowish brown mycelia with scattered monosporous sporangiophore and monosporous sporangia containing sporangiospores on potato dextrose agar (PDA). Monosporous sporangiophore was long, slender and branched at the apex, with each branch bearing a sporangiospore. Sporangium was subglobose in shape and 42.6-112.6 ㎛ in size. Monosporous sporangiola were elliptic, fusiform or ovoid, brown in color, and 9.8-23.4$\times$7.2-12.8 ㎛ in size. Sporangiospores were elliptic, fusiform or ovoid in shape, dark brown or brown in color, 12.9-24.6$\times$8.6-15.4 ㎛ in size, and had three or more appendages. Zygospores were black and 43.6-72.4 ㎛ in size. The fungus grew on PDA at 15-40$\^{C}$, and optimum temperature was 30$\^{C}$. This is the first report on pod rot of cowpea caused by C. cucurbitarum in Korea.

• Korean Journal of Plant Resources
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• v.24 no.5
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• pp.499-506
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• 2011

The purpose of this study was to search available resources for new natural colorants. The extraction efficiency of colorants from black cowpea seed coats and their storage stability were examined according to the various extraction and storage conditions in this study. The results obtained were as follows: the optical density (O.D.) values of the extracted colorants increased with increasing extract time and temperature. Extraction at pH 4 was seen to be the most efficient among the various pH conditions. The color of the extract solutions were seen to change with variation in pH, for example, anthocyanins display color changes from orange-red, to orange, to blue, to greenish-blue at pH 3.0, 4.0-6.0, 7.0 and 9.0-11.0, respectively. The color changes of the extract solutions over various storage periods were determined using UV/Vis spectra these color changes indicate characteristic absorption patterns and a discoloration index which indicates the rate of absorbance (532 nm/454 nm). Methionine addition influenced the storage stability of the colorant solutions and this addition led to better storage stability than non-addition. In paper chromatography of juice extracted colorant, a long stripe was seen on development. Among three colorants obtained via paper chromatography according to development rate, at least two different colorants were mixed indicated by the appearance, or not, of a shoulder at 552 nm depending on the extent of development.

• The Korean Journal of Mycology
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• v.48 no.3
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• pp.297-312
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• 2020

Wilted soybean plants were collected from soybeans cultivation fields in Korea from 2014 to 2016. Fusarium spp., Colletotrichum spp., Rhizoctonia spp., Macrophomina sp., Phytophthora spp., and Calonectria ilicicola were obtained from the infected samples. Out of these, Fusarium spp. were the dominant species (79.1%). In total, 53 isolates were identified as F. solani species complex, F. oxysporum species complex, F. graminearum species complex, and F. fujikuroi species complex based on mycological characteristics. Sequence typing analysis was conducted using translation elongation factor 1 alpha (TEF) to confirm the identification of isolates. All isolates were identified as F. solani, F. oxysporum, F. commune, F. asiaticum, and F. fujikuroi based on phylogenetic analysis of TEF sequences. Pathogenicity of 44 isolates was tested on three cultivars of soybean using the root dip inoculation method. Out of 5 Fusarium species, only F. asiaticum could not cause the symptoms or be weak. Ten isolates were selected based on pathogenic characters and species identification to investigate the host range and screen soybean cultivars for resistance. Fusarium solani, F. oxysporum, and F. commune were aggressive only to soybean, and F. fujikuroi was aggressive to kidney bean, yellow cowpea, black cowpea, adzuki bean as well as soybean. All 13 Korean soybean cultivars were susceptible to F. commune and F. fujikuroi. Out of 13 cultivars, cv. Janggi, cv. Poongsannamul, and cv. Socheongja were resistant to Fusarium wilt, while cv. Hwanggeumol and Chamol were susceptible to Fusarium wilt.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.1
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• pp.1-7
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• 2013

The purpose of this study was to provide basic information for breeding cowpeas (Vigna unguiculata L.) by investigating the crop characteristics of 245 accessions of cowpea collected in Korea and abroad. All specimens flowered within 41 to 50 days (51.5%) or 51 to 60 days (43.7%) of sowing and matured 21 to 30 days (53.9%) or 31 to 40 days (23.7%) from flowering. Thus, the total time from sowing to maturity was either 71 to 80 days (26.9%) or 81 to 90 days (23.4%) for all specimens. The accessions were classified into indeterminate type (72.7%), intermediate type (25.7%) and determinate type (1.6%) based on growth; prostrate type (78.8%) and erect type (21.2%) based on plant type; heart shape (98.4%) and lanceolate (1.6%) based on leaflet shape; and purple (85.2%), white (13.6%) and light green (1.2%) based on corolla color. The accessions were classified into brown (54.7%) and yellowish brown (37.6%) based on color at pod maturity; and downward (90.6%), middle (5.7%) and standing upright (3.7%) based on pod setting position. Seed coat color varied as 25.3% were brown, 23.3% were black, and 20.8% were white. Seed shape also varied as 66.9% were egg-shaped, 24.9% were rectangular and 8.2% were kidney-shaped. Pod lengths ranged from 10.1-20.0 cm and from 20.1-30.0 cm in 89.0% and 8.6% of specimens, respectively. There were 12.1-15.0, 9.1-12.0, and 15.1-18.0 seeds per pod in 62.0%, 25.7% and 9.1% of specimens, respectively. The weight of one hundred seeds ranged from 15.1-20.0 g (37.6%) and 10.1-15.0 g (28.6%). Seed yields per plant were 100.1-200.0 g (52.7%), less than 100 g (22.9%), and 200.1-300.0 g (15.9%). The starch content in the seeds of the seven selected resources ranged from 44.1 to 57.0% while the protein content ranged from 23.3 to 27.5% with significant differences. The sucrose content ranged from 1.46 to 2.03%, also with significant differences.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.9
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• pp.1399-1404
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• 2010

Physicochemical characteristics and antioxidant activities of twelve varieties of legumes and cereals in Korea were analyzed and compared. Crude protein content was higher in legumes (20.60~34.47%) than in cereals (8.96~15.45%). Crude fat contents of soybean (17.73%) and black soybean (18.79%) were higher than other legumes (0.68~1.38%) and cereals (1.01~5.39%). The major minerals were potassium, calcium and sodium, and especially calcium and potassium were high in legumes. Unsaturated fatty acids composition ranged from 66.79% in cowpea to 85.14% in soybean, and $\Omega$-3 fatty acids (linolenic acid) content was higher of 7.47~48.25% in legumes than 0.36~3.71% in cereals. Total polyphenol content was higher 1.32~4.15 mg/g in 80% EtOH extracts from legumes than 0.53~2.83 mg/g in cereals. DPPH and ABTS radical scavenging activities were high values of 62.60% and 264.20 mg AA eq/g, respectively, in EtOH extract from sorghum.