• Mycobiology
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• v.45 no.4
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• pp.392-400
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• 2017

Peanut yield and quality are seriously affected by pod rot pathogens worldwide, especially in China in recent years. The goals of this study are to analyze the structure of fungal communities of peanut pod rot in soil in three peanut cultivars and the correlation of pod rot with environmental variables using 454 pyrosequencing. A total of 46,723 internal transcribed spacer high-quality sequences were obtained and grouped into 1,706 operational taxonomic units at the 97% similarity cut-off level. The coverage, rank abundance, and the Chao 1 and Shannon diversity indices of the operational taxonomic units were analyzed. Members of the phylum Ascomycota were dominant, such as Fusarium, Chaetomium, Alternaria, and Sordariomycetes, followed by Basidiomycota. The results of the heatmap and redundancy analysis revealed significant variation in the composition of the fungal community among the three cultivar samples. The environmental conditions in different peanut cultivars may also influence on the structure of the fungal community. The results of this study suggest that the causal agent of peanut pod rot may be more complex, and cultivars and environmental conditions are both important contributors to the community structure of peanut pod rot fungi.

• Research in Plant Disease
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• v.28 no.1
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• pp.46-50
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• 2022

In June 2017, in Gangneung, Gangwon Province, South Korea, green pea pods exhibited post-harvest rot symptoms. The fungus was isolated from infected pea pods and cultured on potato dextrose agar for identification. The morphological characteristics were examined, sequences of the internal transcribed spacer region and the β-tubulin (βtub) gene were analyzed, and the pathogenicity was confirmed according to Koch's postulates. The morphology, phylogenetic analysis, and pathogenicity tests confirmed that Sclerotinia sclerotiorum was the causal agent. This study reports the first case of post-harvest green pea pod rot caused by S. sclerotiorum in Korea.

• 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.

• The Korean Journal of Mycology
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• v.11 no.2
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• pp.99-101
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• 1983

Black root rot caused by Cylindrocladium crotalariae is one of the most serious soilborne disease in soybean. Plant height reduction of Hwangkeum Kong was 38% by the rotting of the whole main root and 9% by rotting of the half of the main root as compared with partial discoloration in the main root. Pod number per plant and seed weight were significantly reduced by the increase of the disease severity. Important yield components such as number of pods per plant and seed weight were negatively correlated with the soybean black root rot severity.

• 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 Breeding Science
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• v.41 no.4
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• pp.612-615
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• 2009

Lipoxygenase and Kunitz trypsin inhibitor protein are the main antinutritional factor in mature soybean seed. A new soybean cultivar, "Gaechuck#2" with yellow seed coat, lipoxygenase2,3-free and Kunitz trypsin inhibitor protein-free was developed. It was selected from the population derived from the cross between "Jinpumkong2ho" and C242. Plants of "Gaechuck#2" have determinate growth habit with purple flowers, tawny pubescence, yellow seed coat, yellow hilum, oval leaflet shape and brown pods at maturity. Seed protein and oil content on a dry weight basis were 40.7% and 18.7%, respectively. It has shown a 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#2 matured in 4 October with plant height of 54cm and a 100-seed weight of 24.4g. Average Yield of Gaechuck#2 was 230 - 250 kg/10a in 2005 - 2007.

• The Plant Pathology Journal
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• v.36 no.4
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• pp.346-354
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• 2020

Pectobacterium, which causes soft rot disease, is divided into 18 species based on the current classification. A total of 225 Pectobacterium strains were isolated from 10 main cultivation regions of potato (Solanum tuberosum), napa cabbage (Brassica rapa subsp. pekinensis), and radish (Raphanus sativus) in South Korea; 202 isolates (90%) were from potato, 18 from napa cabbage, and five from radish. Strains were identified using the Biolog test and phylogenetic analysis. The pathogenicity and swimming motility were tested at four different temperatures. Pectolytic activity and plant cell-wall degrading enzyme (PCWDE) activity were evaluated for six species (P. carotovorum subsp. carotovorum, Pcc; P. odoriferum, Pod; P. brasiliense, Pbr; P. versatile, Pve; P. polaris, Ppo; P. parmentieri, Ppa). Pod, Pcc, Pbr, and Pve were the most prevalent species. Although P. atrosepticum is a widespread pathogen in other countries, it was not found here. This is the first report of Ppo, Ppa, and Pve in South Korea. Pectobacterium species showed stronger activity at 28℃ and 32℃ than at 24℃, and showed weak activity at 37℃. Pectolytic activity decreased with increasing temperature. Activity of pectate lyase was not significantly affected by temperature. Activity of protease, cellulase, and polygalacturonase decreased with increasing temperature. The inability of isolated Pectobacterium to soften host tissues at 37℃ may be a consequence of decreased motility and PCWDE activity. These data suggest that future increases in temperature as a result of climate change may affect the population dynamics of Pectobacterium.

• Research in Plant Disease
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• v.13 no.2
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• pp.115-118
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• 2007

Sclerotinia rot occurred on the stem and pod of broad bean (Vicia faba) at Gyeongsangnam-do Agricultural Research and Extension Services in Korea from 2004 to 2006. The infected plants showed the typical symptoms; wilted, water-soaked, rotted and eventually died. The colony of the isolated fungus on PDA was white to faintly gray color. Apothecia were cup-shaped and $5{\sim}10\;mm$ in size. Asci were cylindrical in shape and $90{\sim}180{\times}8{\sim}12\;{\mu}m$ in size. Ascospores were ellipsoid and $8{\sim}12{\times}4{\sim}6\;{\mu}m$ in size. Sclerotia formed on the PDA were globose to cylindrical or irregular in shape with black color. The optimum temperature for mycelial growth was $25^{\circ}C$ and sclerotia formation was at $20^{\circ}C$ on PDA. This is the first report on sclerotinia rot of broad bean (Vicia faba) caused by Sclerotinia sclerotiorum (Lib.) do Bary in Korea.

• Korean Journal of Organic Agriculture
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• v.19 no.3
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• pp.357-372
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• 2011

We carried out the experiment to select the suitable sprout soybean varieties for environment-friendly cultivation in paddy field of southern part area, compares of excess moisture injury degree and yield ability among 29 sprout soybean varieties. Plant growth of sprout soybean was generally low in beginning and recovered after flowering due to rainfall. In paddy field cultivation, number of pod per individual and number of seed per individual were less in difference than upland cultivation, and maturing date was delayed 5-14 days than upland cultivation in most species. When environment-friendly cultivation, pest injury was not caused major problem for the growth during the vegetative period of soybean due to ground spider as natural enemy to insect pest. However, damage of stink bugs showed severe during grain filling period, and Dawonkong, Anpyeongkong, Dachaekong and Wonhwangkong showed susceptible to sting bug. SMV infection was weak and showed some necrosis symptoms in Sokangkong, but black root rot was not infected at all. Bacterial pustule began to be infected slowly from pod enlargement stage in most species, displayed severe symptoms in Dawonkong, Pungsannamulkong, Seonamkong and Sobaeknamulkong. The symptoms of pod anthracnose, pod blight and purple spot were greatly appeared after flowering. Disease resistance varieties was Paldokong, Kwangankong, Doremikong, Somyeongkong, Pungsannamulkong, Iksa-namulkong, Seonamkong, Sojinkong, Pureunkong, Bosugkong, Namhaekong and Sorokkong. Lodging index showed 3 in Saebyeolkong, and other species displayed slight lodging in 0-3 degree. 100-seed weight is 9.8-17.2g extent and increased 0.1-3.7g than upland cultivation in most species, but decreased in some species. Government purchase standard, species correspond to small-seed-size namulkong (Sizing screen diameter 4.0-5.6 mm) was Dawonkong, Dachaekong, Bosugkong, Seonamkong, Sokangkong, Hannamkong, Somyeongkong and Wonhwangkong. Species which seed yield was higher than Pungsannamulkong (266kg/10a) were Sorokkong, Hannamkong, Bosugkong and Sowonkong. Considering sprout soybean species, disease endurance, insect resistance, lodging resistance, 100-seed weight, yield ability and excess moisture tolerances synthetically, Seonamkong, Hannamkong, Doremikong, Bosugkong, Pungwonkong, Kwangankong, Sowonkong, Dagikong, Paldokong, Eunhakong and Pungsannamulkong were promising for environment-friendly cultivation in paddy field.

• Korean Journal of Breeding Science
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• v.49 no.3
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• pp.224-229
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• 2017

A new peanut variety 'Daan'(Arachis hypogaea ssp. hypogaea L.) was developed at the Department of Southern Area Crop Science, National Institute of Crop Science (NICS) in Milyang 2014. This was developed from the cross between 'Iksan 31' with Virginia typed short stem and 'Dakwang' with Shinpung-typed larger grain. 'Daan' which is a Shinpung plant type had 13 branches per plant and its length of main stem was 44cm. Each pod has two grains with brown testa and long ellipse-shaped large kernel. Its yield components showed 34 pods per plant, 127 g of 100-seed-weight and 75% of pod shelling ratio in the regional yield trials (RYT). Seed quality showed 47.8% of crude oil and 28.3% of protein content. This variety showed resistant to early leaf spot and had more resistant to late leaf spot, stem rot and lodging, compared to reference variety. In the regional yield trials for 3 years 'Daan' was more productive than reference variety by 16% with 5.00 MT/ha for grain production.