• Journal of Microbiology and Biotechnology
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• v.32 no.9
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• pp.1120-1125
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• 2022

Japanese encephalitis virus (JEV), the causative agent of Japanese encephalitis (JE), is an importantly zoonotic, vector-borne virus widely prevalent in Asia. Although JE has been well controlled in China, its prevalence remains a huge threat to the pig industry as well as human health. Herein, we report on our molecular and serological investigations of JEV among pigs from different regions in Hunan Province of China from 2019 to 2021. Collectively, 19.27% (583/3026, 95% Confidential Interval (CI) 17.86-20.68) of sampled pigs were positive for JEV IgG antibody as revealed by indirect enzyme-linked immunosorbent assay, and the seroprevalence of JEV among pigs was significantly associated with the development stage and breeding scale (p < 0.01). Meanwhile, 10.99% (42/382, 95% CI 7.86-14.13) of tissue samples of pigs with suspected clinical symptoms of JE and 23.44% (15/64, 95% CI 13.06-33.82) of mosquito batches were JEV-positive via reverse polymerase chain reaction. In addition, the complete E gene sequences of 14 JEV strains identified in this study were amplified and sequenced. Phylogenetic analysis showed that all 14 JEV strains belonged to genotype I-b and displayed a distinct genetic relationship to the present JEV vaccine strain (SA14-14-2). In conclusion, our results revealed not only the severe prevalence of JEV in Hunan Province, but also that JEV I-b might be the predominant genotype in Hunan Province, suggesting therefore that effective measures for JE control are urgently needed.

• The Plant Pathology Journal
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• v.38 no.6
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• pp.637-645
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• 2022

Fusarium head blight (FHB) is one of the most serious diseases in barley and wheat, as it is usually accompanied by the production of harmful mycotoxins in the grains. To identify FHB-resistant breeding resources, we evaluated 60 elite germplasm accessions of barley (24) and wheat (36) for FHB and mycotoxin accumulation. Assessments were performed in a greenhouse and five heads per accession were inoculated with both Fusarium asiaticum (Fa73, nivalenol producer) and F. graminearum (Fg39, deoxynivalenol producer) strains. While the accessions varied in disease severity and mycotoxin production, four wheat and one barley showed <20% FHB severity repeatedly by both strains. Mycotoxin levels in these accessions ranged up to 3.9 mg/kg. FHB severity was generally higher in barley than in wheat, and Fa73 was more aggressive in both crops than Fg39. Fg39 itself, however, was more aggressive toward wheat and produced more mycotoxin in wheat than in barley. FHB severity by Fa73 and Fg39 were moderately correlated in both crops (r = 0.57/0.60 in barley and 0.42/0.58 in wheat). FHB severity and toxin production were also correlated in both crops, with a stronger correlation for Fa73 (r = 0.42/0.82 in barley, 0.70 in wheat) than for Fg39.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.191-191
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• 2022

Heterostyly continues to fascinate evolutionary biologists interested in heredity, evolution, breeding, and adaptive function. Polymorphism demonstrates how simply inherited developmental changes in the location of plant sexual associations can have important consequences for population pollination and mating biology. In contrast to homozygous self incompatibility, only a small number of mating phenotypes can be maintained in the population because insect pollinators have limitations in achieving multiple segregation sites for pollen deposition. Field studies of pollen tube growth have shown that reciprocal style-stamen polymorphisms function to increase the capacity of insect-mediated cross-pollination. The genetic pattern of style morphs is well established in various taxa, but despite recent advances, the identity, number, and structure of the genes controlling the heteromorphic syndrome have been poorly elucidated. The phenomenon of heterostyly in buckwheat has been controlled by gene complex concentrate to S-locus. Homomorphic autogamous buckwheat strains were established by the interspecific hybridization. Backcrossing of this line to the common buckwheat (pin) and selecting homostylar progenies made it possible to introduce the self-compatible gene into common buckwheat. In the result, we obtained the BC₉F₂ generation, and defined the strong linkage between flower type and self-incompatibility by microscopic observation of pollen tube growth. This finding suggests that self-incompatibility character is not controlled by one gene. Moreover, we defined the strong linkage between flower type and self-incompatibility. It strongly supports the S supergene theory. Therefore, we have plan to elucidate the heterostyly self-incompatibility by using molecular genetics, proteome analysis and apply to exploitation of buckwheat improvement. In near future, the expression of heterozygous syndromes in genus Fagopyrum with single isolated heterozygous species may provide clues to early stages of polymorphic assembly and shed light on evolutionary models of heterozygous strains.

• Journal of Mushroom
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• v.14 no.4
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• pp.202-206
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• 2016

Oyster mushrooms are widely cultivated and consumed in Korea. P. ostreatus 'Suhan(ASI 2504)' is an ideal cultivar for mushroom farmers due to its dark pileus and thick stipe; however, as it is very sensitive to environmental conditions, an alternative cultivar is required. To develop a new cultivar, parental strains 'Suhan(ASI 2504)' and 'ASI 0665 (Heuktari)' were selected from various collected strains according to morphological characteristics. P. ostreatus 'Soltari' was developed by DiMon crossing between the dikaryotic strain 'Suhan' and the monokaryotic strain derived from 'Heuktari'. Thirty-eight of the 100 crossed strains were selected following analysis of mitochondrial genetic characteristics, and 'Soltari' was ultimately selected by continuous cultivation tests. The mitochondrial DNA profile of 'Soltari' was found to be the same as that of 'Heuktari, and a nuclear DNA profile of 'Soltari' was similar as those of the parental strains, 'Suhan' and 'Heuktari.' 'Soltari' mycelium grows adequately in moderate to high temperatures of $12-20^{\circ}C$, although its optimum temperature was found to be $30^{\circ}C$. Fruiting body production per 1.1-L cultivation bottle was approximately 158.8 g. Its stipe length and thickness were comparable to those of diameter and thickness were somewhat lower (42.72 vs. 51.33 mm and 18.18 vs. 22.46 mm, respectively). 'Soltari' was found to be more resistant to high $CO_2$ atmosphere than 'Suhan', and the color of the pileus of 'Soltari' was dark gray at high temperature. Therefore, it is suggested that this new cultivar 'Soltari' is a good alternative cultivar and will contribute to energy saving in oyster mushroom farms.

• Korean Journal of Breeding Science
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• v.42 no.6
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• pp.711-716
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• 2010

'Sanggang', a new cultivar of Agrocybe aegerita, was bred with mating between monokaryotic strains isolated from 'GMAG45109' and 'GMAG45107' in Mushroom Research Station, Gyonggi Province A.R.E.S. in 2009. The optimum temperature for the mycelial growth of 'Sanggang' was 26 to 28$^{\circ}C$ on PDA(potato dextrose agar) medium. The optimum temperature for the primordia formation and fruiting body development of 'Sanggang', was 18 to 20$^{\circ}C$. In the bottle cultivation of 'Sanggang', the period of spawn running was around 38 days at 22 to 23$^{\circ}C$ and the period from scratching of inoculum to harvest was 12 days. These characteristics of 'Sanggang' were not different from those of 'Mihwang' (control). 'Sanggang' had brown-colored pileus, whereas 'Mihwang' had yellowish brown-colored one. In bottle cultivation, 'Sanggang' hada little smaller but stronger stipe and pilus than 'Mihwang', and 'Sanggang', as well as 'Mihwang', had upright stipe. And 'Sanggang' was shown to have lower veil opening ratio than that of 'Mihwang' at harvest time.The yield of fruiting bodies of 'Sanggang' was 134 g/850ml bottle, which was similar to that of 'Mihwang'. Resistance of'Sanggang' against Trichoderma spp., as well as 'Mihwang', was weak. Freshness of 'Sanggang' was maintained for 13 days under storage temperature 4$^{\circ}C$, while that of 'Mihwang' was maintained for 10 days.

• Journal of Mushroom
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• v.21 no.4
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• pp.241-246
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• 2023

Flammulina velutipesis a popular edible mushroom in South Korea, accounting for approximately 30% of the total mushroom export in the country. Despite its significant position in the domestic mushroom industry, approximately 65% of the cultivated F. velutipes are foreign varieties. To secure variety rights and enhance competitiveness in the export market, there is a need to develop domestic varieties with stable production and excellent shelf life. We focused on breeding a new variety called 'Baekwoon' through mon-mon crossing, using 'Baekseung' and an international collection strain (KMCC02260) as parents. Baekwoon exhibited faster mycelial growth rates at 15 ℃ and 25 ℃ and higher mycelial growth across four tested media compared to that of the control variety. Under bottle cultivation, Baekwoon had a mycelial cultivation period that was shorter by approximately 2 days compared to that of the control. The yield of Baekwoon was 228.0±10.9 g, 8.3% more than that of the control. Furthermore, Baekwoon displayed distinct morphological features characterized by a larger pileus and thicker stipe compared to that of the control variety. Genetic tests confirmed that Baekwoon is genetically different from both parental strains and the control variety. It is expected that the newly developed F. velutipes variety, Baekwoon, will be evaluated for its adaptation in different regions and actively promoted in the field, ultimately increasing the market share of domestic varieties.

• Korean Journal of Poultry Science
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• v.48 no.4
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• pp.193-206
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• 2021

This study aimed to identify the growth performance of Korean indigenous chicken pure-line by sex and twelve strains conserved in Poultry Research Institute, National Institute of Animal Science, Rural Development Administration. The effect of sex and strain on body weight was significantly different in every period, with males being heavier in all periods than females. In the case of biweekly weight gain, the tendency to increase rapidly from birth to six weeks old, and to decrease in the period from twelve to fourteen weeks old was common across all sex and strains. Depending on sex and strain, there were significant differences in age and the number of peaks. Regardless of sex and strain, the determination coefficient and adjusted determination coefficient showed high goodness of fit (99.1~99.9%) to growth functions. However, for each model, the goodness-of-fit had variations by sex and strains. von Betalanffy function had the best fit to growth curves in all the female strains except strain D. On the other hand, Gompertz function had the best fit for all the male strains except strain C. Logistic function showed the lowest goodness-of-fit in all sex and strains. Mature weights were in the order of von bertalanffy, Gompertz, and Logistic models, while growth ratio and maturing rate followed the order of logistic, gompertz, and von bertalanffy functions. This information could be useful for Korean indigenous chicken management and designing crossbreeding tests and breeding programs.

• The Plant Pathology Journal
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• v.33 no.1
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• pp.21-33
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• 2017

Citrus blast caused by bacterium Pseudomonas syringae is a very important disease of citrus occuring in many areas of the world, but with few data about genetic structure of the pathogen involved. Considering the above fact, this study reports genetic characterization of 43 P. syringae isolates obtained from plant tissue displaying citrus blast symptoms on mandarin (Citrus reticulata) in Montenegro, using multilocus sequence analysis of gyrB, rpoD, and gap1 gene sequences. Gene sequences from a collection of 54 reference pathotype strains of P. syringae from the Plant Associated and Environmental Microbes Database (PAMDB) was used to establish a genetic relationship with our isolates obtained from mandarin. Phylogenetic analyses of gyrB, rpoD, and gap1 gene sequences showed that P. syringae pv. syringae causes citrus blast in mandarin in Montenegro, and belongs to genomospecies 1. Genetic homogeneity of isolates suggested that the Montenegrian population might be clonal which indicates a possible common source of infection. These findings may assist in further epidemiological studies of this pathogen and for determining mandarin breeding strategies for P. syringae control.

• International Journal of Industrial Entomology and Biomaterials
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• v.8 no.1
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• pp.43-49
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• 2004

Ten promising polyvoltine mulberry silkworm strains(SDMGl, SDMG2, SDMG3, SDMG4, SDMWl, SDMW2, RMWl, RMW2, RMW3 and RMW4) that are superior in quantitative and qualitative traits have been synthesized in the polyvoltine breeding laboratory of Andhra Pradesh State Sericulture Research ＆ Development Institute, Hindupur through systematic hybridization and appropriate selection methods. After the genotypes were found homozygous for the desired traits, they have been crossed with 3 bivoltine testers $(APS8, APS4 and {NB_2}{D_4})$ and thirty new hybrid combinations were developed for the assessment of their hybrid performance. Phenotypic expressions of economically important quantitative and qualitative traits of fist filial generation were measured and subjected for statistical analysis. Evaluation Index and Subordinate Function methods were employed for the assessment of hybrid performance since they are widely used in silkworm hybrid evaluation. Total of seven poly${\times}$bivoltine combinations, which ranked high in both the methods, were selected as potential combinations for further field test. These combinations also ranked significantly higher than the control hybrid (APMl${\times}$APS8).

• Korean journal of applied entomology
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• v.38 no.3
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• pp.249-253
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• 1999

To study races of Heterodera glycines in Korea, 21 soil samples were collected from eight provinces in 1995. Four races were found; race 3(48%) was a dominant race flowed by race 5(24%), race 1(19%), and race 6(9%). About 30~40% of H. glycines populations reproduced on Pickett and PI88788, while non reproduced on Peking or PI90763. Development of resistant soybean cultivar targeting to race 5 and 6 of H. glycines using PI90763 and PI88788 as a parent is recommended.