• The Korean Journal of Mycology
• /
• v.22 no.4
• /
• pp.378-385
• /
• 1994

Interspecific somatic hybrids were obtained by protoplast fusion between Pleurotus ostreatus and Pleurotus sajor-caju. The fusion products between incompatible strains did not form clamp connections. Fruiting body of the clampless fusants was induced by light-dark cycle on saw-dust-rice bran substrate in glass bottles. Out of them, seven somatic hybrids produced fruiting bodies of intermediate morphology of the two species. Light and low temperature were the initiating factors for the development of clamped hyphae from the clampless mycelial colonies. All of these basidiocarps had clamp connections. Eight fusants from the six crosses were analysed with the segregation of genetic characters by random spore isolates. In the three combinations, unexpected alleles were shown. Somatic hybrid between P188 (P. ostreatus 2-1 + P. sajor-caju 2-53) and P. florida 2-3 by triple cross produced fruiting bodies similar to those of fusant between P. ostreatus and P. florida. All the genetic charaters from the three strains were shown to segregate and recombine.

• Korean Journal of Plant Tissue Culture
• /
• v.22 no.4
• /
• pp.229-234
• /
• 1995

Anthers of hybrids and inbred lines of Chinese cabbage (Brassica campestris ssp. pekinensis) were inoculated on the modified solid or liquid B$_{5}$ medium after several pre-treatments. Anthers were then maintained at 25 $^{\circ}C$ after being subjected to various post-treatment. Somatic embryos began to appear 9 days after inoculation and ended at 13th days. Low temperature pre-treatment did not increase embryoid production whereas high post-treatment temperature of 4$0^{\circ}C$ or 45$^{\circ}C$ enhance the production. There were considerable levels differences in embryogenesis between lines used, but not between the culture methods. Somatic embryo yield was also increased by subjecting anthers to one day at 35$^{\circ}C$ and then another one day at 3$0^{\circ}C$ after plating. Histological observations showed several stages in haploid development ranging from a few celled to large multiple-celled embryoids.s.

• Journal of Mushroom
• /
• v.12 no.3
• /
• pp.171-180
• /
• 2014

The primary objective of the present study is the characterization of the hybrids of monokaryon- monokaryon (mono-mono) crosses in mushroom breeding. We employed this technique for developing superior strains from Pleurotus species strains with 85 mono-mono intraspecific hybrids of 7 combinations between six Pleurotus ostreatus strains and one Pleurotus florida strain. In this study, the results of analysis on hybridization rate, nuclear DNA patterns, and colors and yields of fruit-bodies, are presented as follows. The crossability between mono-mono crossing ranges between 50 and 93.75%. The results of the analysis on the nuclear DNA patterns of 85 hybrid strains of mono-mono crosses share the nuclei of both parents, but their genetic similarities were predominated by either parent. The hybrid strain between P. florida and P. ostreatus showed patterns more similar to P. florida, while the hybrid strain between P. ostreatus and P. ostreatus either had patterns predominated by either parent strain. The fruiting body colors of the mono-mono crosses mostly had combined colors of both parents but showed the tendency of being more similar to that of either parent. 82% of the hybrid strain indicated similar fruiting body yields compared to both parent strains, while 0% was higher and 18% were lower than both parents. The present study was able to find out and suggest superior hybrid trains by identifying the nuclear DNA patterns of hybrids between Pleurotus species as well as the characteristics of their fruiting bodies. This study expects that the advantages of the mono-mono crossing are needs to be fully utilized in mushroom breeding and it is better to develop superior strains of Pleurotus species strains together with the mono-mono crossing.

• Journal of Mushroom
• /
• v.5 no.1
• /
• pp.34-38
• /
• 2007

The white-colored and the dark gray-colored mutants were frequently happened in cultivated areas of Pleurotus ostreatus (Wonhyeong-neutari). These caused conflicts between farmers and spawn companies. Our studies were conducted to elucidate the mechanism of mutagenesis. The results from the studies would provide valuable informations that could be used to prevent the color-related mutation, and also will be applied in breeding programs of P. ostreatus. Oyster mushroom variety, Wonhyeong-neutari, is somatic hybrid of Pleurotus and has genetic makers for arginine, ornithine, proline, riboflavine. Genetic markers analysis of monospore isolates derived from color mutants show identical tendency with that of Wonhyeong-neutari, these results indicate that color mutants were derived from Wonhyeongneutari. Twenty-one and four homokaryons were selected from the white-colored mutant MGL 2205 and gray-colored ASI 2029. All 34 F1 hybrids derived from the white-colored mutant MGL 2205 produce white-color fruiting bodies, indicating that the white color trait is heritable. In the first generation hybrids between the white-colored MGL 2205 and the gray-colored ASI 2029, all 16 hybrids produced pigmented fruiting bodies. Homokaryons isolated from the hybrid MGL 2205 X ASI 2029 were mated with homokaryon tester strains derived from MGL 2205. By these result, we could assumed that white color trait is a heritable character which is controlled by more than one recessive gene.

• Horticultural Science & Technology
• /
• v.33 no.1
• /
• pp.83-92
• /
• 2015

xBrassicoraphanus line BB#5, a new synthetic intergeneric hybrid between Brassica rapa L. ssp. pekinensis and Raphanus sativus L. var. rafiphera induced by N-methyl-N-nitroso-urethane mutagenesis in microspore culture, shows high seed fertility and morphological uniformity. Dual-color fluorescence in situ hybridization (FISH) using 5S and 45S rDNA probes and genomic in situ hybridization (GISH) using B. rapa genomic DNA probe were carried out to analyze the chromosome composition and the meiosis pairing pattern compared to its parental lines. The somatic chromosome complement is 2n = 38, which consists of 17 metacentric and two submetacentric chromosomes with lengths of 2.18 to $5.01{\mu}m$. FISH karyotype analysis showed five and eight pairs of 5S and 45S rDNA loci. GISH meiosis pairing analysis showed that 19 complete bivalents were most frequent and accounted for 42% of the 100 pollen mother cells examined. Based on chromosome number, size, morphology, rDNA distribution, and meiosis pairing pattern, both parental genomes of B. rapa and R. sativus appear to exist in xBrassicoraphanus line BB#5, demonstrating its genome integrity. Such stable chromosome constitutions and meiotic pairing patterns in somatic and meiotic cells are very rare in natural and synthetic intergeneric hybrids. Chromosomal studies and genetic and phenotypic changes in allopolyploids a re discussed. The results p resented h erein will b e usef ul f or f urther g enomic s tudy o f xBrassicoraphanus lines and their improvement as promising new breeding varieties.

• Korean Journal of Breeding Science
• /
• v.41 no.4
• /
• pp.468-473
• /
• 2009

Fluorescence in situ hybridization (FISH) and genomic in situ hybridization (GISH) were used for chromosome analysis of hybrids (2n=16) between onion (Allium cepa L., 2n=2X=16) and welsh onion (A. fistulosum L., 2n=2X=16). 5S rDNA, 45S rDNA, and tandemly repeated DNA (TSD) sequence were used as probes for FISH analysis. A. fistulosum specific DNA probe of telomeric repeats and A. fistulosum DNA were used for GISH analysis. In the analysis of meiotic chromosome GISH revealed that hybrids have 7 bivalants and 2 univalents chromosome and 2 univalents were derived from A. fistulosum chromosomes. In somatic chromosomes of hybrid each 8 chromosomes were derived from A. cepa and A. fistulosum, respectively. FISH signal of 45S rDNA probe in A. fistulosum was detected at secondary constriction of chromosomes, while FISH signal in A. cepa was observed in both secondary constriction and telomere of chromosomes. TDS signals in A. fistulosum chromosomes were detected at all subtelomeric of 8 chromosomes and also in 2 pericentromeric of the chromosomes, whereas TDS signals in A. cepa were observed only in subtelomeric in all chromosomes. The pattern of TDS signal in hybrid chromosomes was similar to those of A. fistulosum chromosomes.

• Korean Journal of Plant Tissue Culture
• /
• v.22 no.6
• /
• pp.311-316
• /
• 1995

In an attempt to obtain intersubgeneric somatic hybrids of Pelargonium aridum and P.zonale, protoplast isolated from the two species were fused by using polyethylene glycol(PEG) and electorfusion methods. Protoplast were isolated from cotyledon and leaf tissues using MS medium containing 550 mM sucrose, 0.7% cellulase (Onozuka R-10) and 0.4% Macerozyme. The optimum number of protoplasts per mL of culture medium was 6 x 10$^4$. Protoplast fused by the electrofusion method were more active than by PEG method. Heterokaryotically fused protoplasts formed calli when cultured in MS medium containing 550 mM glucose, 1 to 2 mg/L NAA and 0.5 to 1 mg/L BA.

• The Korean Journal of Mycology
• /
• v.21 no.3
• /
• pp.200-211
• /
• 1993

Somatic hybrids of Pleurotus florida ASI 2016 and Pleurotus ostreatus ASI 2018 were obtained by protoplast fusion. The 40 fusants($P1{\sim}P40$) was examined for the yield on fermented and pasteurized rice straw in a tray. The carpophore yield of them were showed as the range of $27.0{\sim}155.2$, based on parental values of 100(ASI 2018), The pilei of fusants between orange white colored P. florida and dark grey colored P. ostreatus had mixed colors in the young stage. Other breeding programmes were performed to improve new varieties with high yield and good quality. A new oyster mushroom variety, Wonhyeongneutaribeosus(P72), was developed at the Agricultural Sciences Institute, Rural Development Administration in 1990. This P.florida-ostreatus-ostreatus hybrid P72 was selected from 38 protoplast fusion products($P41{\sim}P78$) between P.florida-ostreatus recombinant P5-M 43-arg rib and P. ostreatus ASI 2-13-0 2001-19-pro orn. The yield indexes of 38 hybrids ranged $40.5{\sim}152.7$ compared with the parental values of 100(ASI 2001). Hybrid P72 was characterized by the large fruiting bundle of semispherical shape with long stipe and by the small and circular pileus, resulting in lower harvesting cost. A significant increase in carpophore production was observed in somatic hybrids of protoplasts due to heterosis. A comparision of hybrid with parents P72 was made using isozyme analysis. The esterase banding patterns could be characterized by new bands in the hybrids. Seven fusion products of four crosses between P.florida ASI 2016 and P. ostreatus ASI 2018 were analysed with respect to the distribution of progenies and segregation of gene markers by random basidiospore analysis. Segregation of alleles should yield progeny of four genotypes in a Mendelian ratio of 1 : 1 : 1 : 1 for prototrophs, auxotrophs of one parental type, auxotrophs of the other parental type, and auxotrophic recombinants, respectively. However, five fusants of them did not detect one parental, P.ostreatus, type. Basidiospores could yield progeny of 16 genotypes in the cross of one of the recombinant P5-M43-arg $rib{\times}P. ostreatus$ ASI 2-13-pro orn but the segregants of three fusants were not detected clearly. The allele ratio of loci could be expected 1 : 1 : 1 : 1 for arg, rib, pro and orn. The ratio, however, would be changed to 4 : 1 : 1 : 1 with increasing proportion of argo In almost all the fusants, prototrophic recombinants were recovered in large numbers against auxotrophic markers. Parental genotypes were recovered with the recombinant progeny amounting to $38.68{\sim}99.56%$. The analysis provides proof of heterokaryosis and strong evidence for haploidy of vegetative nuclei, a sexual cycle consisting of nuclear fusion and meiosis.

• 한국균학회소식:학술대회논문집
• /
• 2014.05a
• /
• pp.13-13
• /
• 2014

Two kinds of mushrooms, Gumji (金芝; Ganoderma) and Soji, were described in old book of Samguksagi (History of the three kingdoms; B.C 57~A.D 668; written by Bu Sik Kim in 1145) in Korea-dynasty. Many kinds of mushrooms were also described in more than 17 kinds of old books during Chosun-dynasty (1392~1910) in Korea. Nowadays, mushroom cultivation has been increased through out the world last decade years. Production of mushrooms has also been increased 10-20% and many varieties have been cultivated. Similar trends were also observed in Korea. Approximately two hundred commercial strains of 37 species in mushrooms were developed and distributed to cultivators. Somatic hybrid variety of oyster mushroom 'Wonhyeong-neutari' were developed by protoplast fusion, and distributed to grower in 1989. The fruiting body yield index of somatic hybrids of Pleurotus ranged between 27 and 155 compared to parental values of 100 and 138. In addition, more diverse mushroom varieties such as Phellinus baumi, Auricularia spp., Pleurotus ferulae, Hericium erinaceus, Hypsizigus marmoreus, Grifola frondosa, Agrocybe aegerita and Pleurotus cornucopiae have been attempted to cultivate in small scale cultivation. Production of mushrooms as food was 190,111 metric tons valued at 800 billion Korean Won (one trillion won if include mushroom factory products; 1dollar = 1,040 Won) in 2011. Major cultivated species are Pleurotus ostreatus, Pleurotus eryngii, Flammulina velutipes, Lentinula edodes, Agaricus bisporus, and Ganoderma lucidum, which cover 90% of total production. Since mushroom export was initiated from 1960 to 1980, the export and import of mushrooms have been increased in Korea. Technology developed for liquid spawn production and automatic cultivation systems lead to the reduction of the production cost resulting in the increasement of mushroom export. However some species were imported because of high production cost for these mushrooms requiring the effective cultivation methods. Developing of effective post-harvest system will be also directly related to mushroom export. In academic area, RDA scientists have been conducting mushroom genome projects. One of the main results is the whole genome sequencing of Flammulina velutipes for molecular breeding. An electrophoretic karyotype of of F. velutipes was obtained using CHEF with 7 chromosomes, with a total genome size of approximately 26.7 Mb. The mususcript of the genome of F. velutipes was published in PLOS ONE this year. For medicinal mushrooms, we have been conducting the genome research on Cordyceps and its related species for developing functional foods using this mushroom. In 2013, Korea Food and Drug Administraion (KFDA) approved Cordyceps mushroom for its value as an immune booster.

• Journal of Plant Biotechnology
• /
• v.38 no.1
• /
• pp.69-76
• /
• 2011

This study describes the effect of myo-inositol on sustained cell division and plant regeneration from cotyledon-derived protoplast of cabbage (Brassica oleracea var. capitata). Freshly isolated protoplasts were cultured in modified Murashige and Skoog (MS) medium removed ammonia ions and containing $0.4\;mg\;l^{-1}$ thiamine HCl, $100\;mg\;l^{-1}$ myo-inositol, $2\;mgl^{-1}$ 2,4-D, $0.5\;mgl^{-1}$ BA, $30\;gl^{-1}$ sucrose and several concentrations of myo-inositol (2, 4, 6, 8, 10% (w/v)) as an osmotic stabilizer. After 3 weeks of culture in the dark at $25^{\circ}C$, the plating efficiency of cabbage protoplasts reached to $22.5{\pm}2.9%$ when cultured in modified MS medium supplemented with $2\;mgl^{-1}$ 2,4-D, $0.5\;mgl^{-1}$ BA, $30\;gl^{-1}$ sucrose and 8% (w/v) of myo-inositol at a density of $2{\times}10^5$ protoplasts/ml. Rapidly growing cell colonies after 3 weeks of culture were transferred to the same culture medium removed osmoticum. To induce shoot regeneration from calluses, calluses with about 2 mm in diameter were transferred to the MS medium containing $2\;mgl^{-1}$ BA and $0.5\;mgl^{-1}$ NAA. After further three weeks of incubation onto the medium in the light, green shoots were formed on the surface of calluses at a frequency of 30%. Upon transfer to half-strength MS basal medium, roots were formed onto the bottom of regenerated shoots without auxin treatments. These regenerated plantlets were successfully acclimatized to soil transfer, grown to normal mature plants. The cabbage protoplast culture system established in this study could be applied for production of somatic hybrids or cybrids by asymmetric protoplast fusion and mass proliferation of elite somatic clones of cabbage.