• Mycobiology
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• v.46 no.4
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• pp.421-428
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• 2018

The white button mushroom (Agaricus bisporus) is one of the most widely cultivated species of edible mushroom. Despite its economic importance, relatively little is known about the genetic diversity of this species. Illumina paired-end sequencing produced 43,871,558 clean reads and 69,174 contigs were generated from five offspring. These contigs were subsequently assembled into 57,594 unigenes. The unigenes were annotated with reference genome in which 6,559 unigenes were associated with clusters, indicating orthologous genes. Gene ontology classification assigned many unigenes. Based on genome data of the five offspring, 44 polymorphic simple sequence repeat (SSR) markers were developed. The major allele frequency ranged from 0.42 to 0.92. The number of genotypes and the number of alleles ranged from 1 to 4, and from 2 to 4, respectively. The observed heterozygosity and the expected heterozygosity ranged from 0.00 to 1.00, and from 0.15 to 0.64, respectively. The polymorphic information content value ranged from 0.14 to 0.57. The genetic distances and UPGMA clustering discriminated offspring strains. The SSR markers developed in this study can be applied in polymorphism analyses of button mushroom and for cultivar discrimination.

• Journal of Mushroom
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• v.19 no.3
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• pp.246-250
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• 2021

The main characteristics of a new cultivar 'Jinhyang', a cross of a collection of monokaryotic strains of the brown button mushroom, were examined. 'Jinhyang' was not significantly different from the control cultivar 'Dahyang' in mycelial culture and cultivation period. The cap of 'Jinhyang' was thicker and darker in color than that of 'Dahyang'. The hardness and individual weight of the fruiting body of 'Jinhyang' were slightly higher than those of 'Dahyang'; however, the differences were not significant. The yield of 'Jinhyang' was 14.1 kg/m², which was 8% higher than that of 'Dahyang'. Therefore, it is expected that it will be possible to supply this cultivar growers in the future.

• The Korean Journal of Mycology
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• v.13 no.1
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• pp.1-10
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• 1985

This experiment was undertaken to investigate proper conditions for protoplast isolation from strains of Agaricus bisporus, Flammulina velutipes, Lentinus edodes, Pleurotus florida, Pleurotus ostreatus, Pleurotus sajor-caju and Volvariella volvacea. Combination of ${\beta}-D-glucanase$, novozym 234 and snail enzyme with 0.6M $MgSO_4$ in 0.05M Na-maleate buffer, pH 5.8 was the most effective for isolation of protoplasts. High yields of protoplasts were obtained from $4{\sim}5$ days old mycelia of P. florida and P. ostreatus on mushroom complete agar medium. Protoplasts were also obtained in good yield from other fungi but A. bisporus and V. volvacea. In the latter two cases protoplast release was observed; however, the yield was much lower than those of the other fungi.

• Journal of Mushroom
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• v.16 no.4
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• pp.279-286
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• 2018

The button mushroom, Agaricus bisporus, is one of the most widely cultivated mushrooms. The domestic production of cultivated mushrooms in 2016 was approximately 10,173 tons, with a total value of 59 billion won. Currently, 10 cultivars have been developed; however, Korean farmers continue to demand new cultivars of mushrooms with improved quality. To breed superior lines, KMCC00754 and KMCC00775 were selected as mother strains from the 170 collected genetic resources. The putative homokaryotic strains were 25 strains from the 120 SSIs of KMCC00754 and six strains from the 120 SSIs of KMCC00775 selected by using the AbSSR45 marker. These homokaryotic strains were crossed with each other and the crossing was confirmed by SSR analysis. Seventy-four lines were crossed into 150 lines for a 50% ratio of crossing. Abs2-2015-16 was selected as a superior line by three cultivations. A new cultivar, 'Dodam', was developed in 2017.

• Korean Journal Plant Pathology
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• v.14 no.4
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• pp.350-357
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• 1998

A total of 12 strains of fluorescent Pseudomonas isolated from the cultivated mushrooms such as Agaricus bisporus and Pleurotus ostreatus were collected. They consisted of pathogenic Pseudomonas spp. and epiphytic Pseudomonas spp. of the cultivated mushroom. To analyze the phylogenetic relationship of these strains, ITS I region, the 16S-23S intergenic spacer region in the ribosomal RNA (rRNA) operon, was cloned and sequenced. The spacer regions of these strains were 495∼527 nucleotides in length and contained the genes encoding isoleucine-tRNA (tRNAIle) and alanine-tRNA (tRNAAla). The reciprocal homologies of each ITS I sequence among these strains were in the range of 84.2%∼98.8%. According to the analysis of ITS I sequences, the fluorescent Pseudomonas spp. were phylogenetically classified into three clusters. Cluster I consisted of Pseudomonas fluorescens, P. tolaasii, P. gingeri’, and P.‘reactans’(WLRO). Cluster II comprised Pseudomonas fluorescens biovar C and F. Cluster III composed P. agarici. Cluster I and II could be classified into P. fluorescens complex. P. agarici formed an independent taxon clearly separable from P. florescens complex.

• Journal of Mushroom
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• v.11 no.2
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• pp.53-62
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• 2013

A total of 35 phosphate solubilizing bacterial strains were isolated from waste mushroom bed of Agaricus bisporus in Buyeo-Gun, Chungnam and screened for the production of indole acetic acid (IAA). The best IAA producing strain was identified as Pantoea rodasii using 16S rRNA analysis. In addition to the IAA production, this strain could act as an efficient phosphate solubilizer (1100 ${\mu}g$ $ml^{-1}$ after 5 days of incubation) also. The selected strain was cultured under different conditions in order to assess the optimum conditions for maximum IAA production. The nutrient broth (NB) medium was recorded as the best medium, where the maximum IAA production (229 ${\mu}g$ $ml^{-1}$) was recorded at the start of stationary phase (12 hours after inoculation) of the bacteria growth. The performance of the strain was found to be maximum at the temperature of $30^{\circ}C$ followed by $25^{\circ}C$. IAA production was found to be increased with increasing tryptophan concentration (from 0.1 to 0.6%), however beyond this limit, a slight reduction in IAA production was observed. The strains' ability to produce IAA was further confirmed by extraction of crude IAA and subsequent TLC analysis. A specific spot from the extracted IAA preparation was found corresponding with the standard spot of IAA with same $R_f$ value. The results of HPLC analysis conducted in identifying and quantifying the IAA production more precisely, are in agreement with the results of the assessment done with colorimetric method. As revealed by the results of the pot experiment, the isolated strain could significantly enhance the growth (as measured by shoot and root growth) of mung bean plants compared to that of non-inoculated plants. Therefore it can be concluded that the present strain, Pantoea rodasii has great potential to be used as bio-inoculants.

• The Korean Journal of Mycology
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• v.9 no.2
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• pp.93-97
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• 1981

The new strains of Mycogone perniciosa which could attack cream colored mushroom were collected and tested to find out their characteristics in comparison with the original strains. The optimum temperature for mycelial growth was $25^{\circ}C$, showing no difference between strains, but optimum pH was 6.0 for the original strains and pH 7.0 for the new ones. New strains did not survive at $50^{\circ}C$ for 60 minutes while original ones 40 minutes. Delan and Hamai were effective for controlling new strains and the mushroom strains which have scales showed resistance to the new strains of Mt. perniciosa regardless of the mushroom colors.

• The Korean Journal of Mycology
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• v.18 no.2
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• pp.96-101
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• 1990

This study was conducted to select the promising antifungal microoganisms for biological control of wet bubble, Mycogone perniciosa. Ninty one isolates of fungi, 342 isolates of bacteria, and 556 actinomycetes were isolated from mushroom composts and soils, were subjected to primary screening test on agar medium base for their antimicrobial spectra. Among them, 12 bacteria and 71 actinomycetes were selected. Among the antibiotic producing microoganisms, 5 cultures were selected on the basis their antibiotic activities on casing soil with Benlate nontolerence M. perniciosa. Finally, AJ-117, AJ-136 and AK-139 were selected as microoganism with antifungal activity against two strains of M. perniciosa.

• The Korean Journal of Mycology
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• v.44 no.2
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• pp.94-99
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• 2016

Since development of the first Korean button mushroom cultivar 'Sae-Ah' in 2010, mushroom farmers have demanded an improved cultivar. Although a new cultivar, 'Saejeong', was developed in 2011, this cultivar has thus far been difficult to cultivate in typical mushroom farms. To solve this problem, another new cultivar, 'Saedo', was developed in 2012. This new cultivar was selected by genetic analysis from crossing the heterokaryon line A175 and the homokaryon line ASI1346-15. The heterokaryon A175 was a crossed line between strains ASI1038-211 and ASI1346-20. The mycelium of 'Saedo' showed good growth on compost dextrose agar at $25^{\circ}C$. The morphological traits such as the pileus (cap) and stipe of the 'Saedo' cultivar were thicker than those of the reference control 'Saejeong', and the production yield was increased by 1.89-fold compared to that of the reference control. A field experiment of the 'Saedo' cultivar has been ongoing since 2013. The yield of the 'Saedo' cultivar was found to be substantially higher than that of the reference control during the $2^{nd}$ flush.

• Journal of Mushroom
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• v.1 no.1
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• pp.1-8
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• 2003

Mushroom cultivation in Korea was launched in the early 1960's. At that time Korean government started a program for increasing cultivation of button mushroom (Agaricus bisporus) and oak mushroom (Lentinula edodes) to export agricultural products and to increase farm income. National research institutes under Rural Development Administration, Korea Forest Service, etc. play a leading role in mushroom industry as follows : Development and spread of genetically superior commercial strains, good spawns, and cultivation techniques. Training and field advice to lead farmers for mass production of high quality mushrooms. Political support of facilities and establishments for mushroom cultivation. Several mushrooms including oak mushroom, button mushroom, oyster mushroom, winter mushroom, Ganoderma, P. eryngii, etc. have been popularized for their cultivation techniques and produced in large quantities in the farm. According to a recent statistics, mushrooms have been grown by about 20,000 farm households, in Korea and the gross production of fresh mushrooms is estimated about 170,000 M/T. The gross production of oyster mushroom is the highest followed by winter mushroom, oak mushroom and button mushroom. The gross amount of mushroom production stands over 700 billion won. Thus, mushroom industry goes to the most important cash crop to be produced yearly.