• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.37-37
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• 2003

Intraspecific hybrids have been proven to be a useful tool for increase growth rate in some freshwater fish species. However the effects of intraspecific hybrids in seawater fish species is little known. To assess whether intraspecific hybrids in red sea bream was associated with growth enhancement, growth performances of offspring from two inbred lines, selected Korean line (KORDI-F4) and cultured Japanese line (IPN) and two intraspecific hybrids lines (KORDI-F4♀×JPN♂ and JPN♀×KORDI-F4♂) of red sea bream were compared. There's no significant difference in body weight between offspring groups during seed production period (until 4 months old). At seven months old (after three months rearing trials on sea cages communally), the offspring from KORDI-F4 (41.0±11.1g) and JPN♀×KORDI-F4♂ (39.3±8.1g) showed significantly better performance in body weight than that of the offspring from KORDI-F4♀×JPN♂ (37.0±8.1g) and IPN (35.7±9.7g). At 15 months old, the offspring from JPN♀×KORDI-F4♂ showed best growth performances in body weight, weight gain, specific growth rate among four offspring groups. As the results, the intraspecific hybrids between cultured Japanese line and selected Korean line showed superior growth performances than their paternal and maternal inbred lines.

• Korean Journal of Microbiology
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• v.27 no.2
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• pp.98-107
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• 1989

Intraspecific fusants, produced by protoplast fusion of auxotrophic mutants from Trichoderma koningii ATCC 26113, were segregated into various strains including parental types, non-parental auxotrophic hybrids, and prototrophic hybrids on complete plate. Interestingly, some of non-parental prototrophic hybrids revealed to have enhanced cellulolytic activity incomparison with other strains of parents or hybrids derived thereafter. It was also evident that prototrophic hybrids of aneuploid could be constructed after the spontaneous segregation of complementing fusants produced through the protoplast fusion.

• The Korean Journal of Mycology
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• v.17 no.3
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• pp.154-160
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• 1989

The nuclear transfer technique was employed to obtain intraspecific hybrids in Aspergillus nidulans. Nuclei isolated from either a wild type or an auxotrophic mutant strain (FGSC 475) were transferred into the protoplasts of a recipient strain (FGSC 514). The frequency of hybrid formation (4.8% and 10.1 %, respectively) by nuclear transfer was higher than the frequency (0.6%) by protoplast fusion. Furthermore, most of the hybrids formed showed increased activity of some components of cellulase system, xylanase system, and mannanase. The hybrids were analyzed to be either diploid or aneuploid. These results suggest that nuclear transfer technique is more efficient the formation of intraspecific hybrids than protoplast fusion method and is useful for the improvement of Aspergillus strains.

• Plant Resources
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• v.7 no.2
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• pp.87-92
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• 2004

Five different poplar hybrids were tested for rescuing embryo to elongate in vitro plantiets after hybridization. Ovaries and ovules were cultured on Woody Plant Medium (WPM) supplemented with cytokinins, 6-benzylamine (BA) and zeatin. Multiple shoots were initiated from half section of capsule with immature embryos after 21 days from pollination and tiny shoots were formed after the expansion of cotyledons in ovule cultures. Germinating response was better in intraspecific hybrids $(6.53\pm1.66)$ than interspecific crosses $(0.93\pm0.54)$ from half section of capsules on WPM medium. In general, zeatin was better than BA in inducing multiple shoots from isolated ovules. The highest average number $(19.40\pm4.53)$ of shoots was produced from immature ovules of 21 days post-pollination of WPM medium supplemented with 5.0 mg/L zeatin. The highest percentage of germination was 93% from the half section of in vitro ovary cultures. Soil acclimation was successfully conducted in cell tray containing artificially mixed soil with 96% survival rate.

• Korean Journal of Microbiology
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• v.24 no.2
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• pp.91-97
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• 1986

Intra and interspecfic fusants were produced by the protoplast fusion of auxotrophic mutants from Trichoderma koningii ATCC 26113 and Trichoderma reesei QM 9414. It was found that 0.6M $MgSO_4\;and\;0.6M\;NH_4Cl$ was the best osmotic stabilizer for the preparation of protoplasts from the mycelium of T. koningii and T. reesei respectively. However, $MgSO_4$ was the most suitable one for the regeneration of the protoplasts from both species. The intraspecific protoplast fusion frequencies between the auxotrophic mutants from T. reesei were $1.8{\times}10^{-2}\;to\;5.1{\times}10^{-1}$. Interspecific protoplast fusion frequencies between the auxotrophic mutants from T. koningii and T. reesei were $3.6{\times}10^{-3}$\;to\;8.4{\times}10^{-2}. Interspecific complementing fusants, however, were not alwats produced. Fusants obtained from interspecific potoplast fusion were spontaneously segregated into various strains including parental types, non-parental auxotrophic hybrids, and prototrophic hybrids on complete plate. Interspecific hybrids revealed to have partially enhanced celluloytic activities.

• Journal of Korean Society of Forest Science
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• v.46 no.1
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• pp.53-56
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• 1980

We observed performance of segregation in flower color and type of hybrids which obtained from crossing of intra species in Hibiscus syriacus. Obtained results were followings. 1. The purple flower was dominance to the white one and this was presumed that was owing to cytoplasmic heredity. 2. Single and double petal of flower was presumed that was originated from factors of Ss and dd. 3. There was not variation in flower color and type of $F_1$ hybrid between 4 n and 2 n Hibiscus syriacus. 4. There were many variation of flower color among $F_1$ hybrids which abtained in open pollination of Hibiscus syriacus. 5. We could observe many flowers variegated with red color among $F_1$ hybrids which obtained in crossing between double petal flowers of Hibiscus syriacus.

• Journal of Mushroom
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• v.12 no.2
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• pp.96-106
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• 2014

The primary objective of the present study is the characterization of the somatic hybrids of dikaryon-monokaryon (di-mono) crosses in mushroom breeding. We employed this technique for developing superior strains from Pleurotus ostreatus strains with 48 intraspecific hybrids of 12 combinations between six P. ostreatus strains and one P. florida strain. The results on the experiments of hybridization rate, nuclear DNA patterns, and colors and morphology of fruit-bodies, are presented. In di-mono crosses, somatic hybrids among Pleurotus strains showed 100% of crossability as seen in those between P. ostreatus and P. florida strains indicating that the nuclei of a dikaryon is inferred to be migrated to a recipient. 87.5% of the somatic hybrids among Pleurotus strains were similar to the donor dikaryons, and 12.5% of the somatic hybrids presented DNA patterns of both parents. In 16.6% of di-mono crosses between P. ostreatus and P. florida, the nuclear DNA patterns of all hybrids showed the same or similar patterns compared to the donor dikaryons. 70.9% of the hybrids between P. ostreatus and P. ostreatus were similar to the donor dikaryons and 12.5% of them presented the DNA patterns of both parents. 79.2% of fruiting body morphology of the hybrids among Pleurotus strains were similar to the dikaryons and 20.8% of them were similar to both parents. Interestingly, the morphology of all dikaryons were dissimilar each other. All hybrid strains between dikaryon P. florida and monokaryon P. ostreatus showed the fruiting body of which colors were similar to those of the dikaryon, while the hybrids between dikaryon P. ostreatus and monokaryon P. florida were showed the combined colors of both parents. Therefore, the fruiting body color of P. florida tends to be generally dominant. In conclusion, the present study provides a way to find out and suggest superior hybrid strains using the nuclear DNA patterns of hybrids between Pleurotus strains as well as the characteristics of their fruiting bodies. The advantages of the di-mono crossing are needs to be fully utilized in mushroom breeding because it is an ideal way to develop the superior strains of Pleurotus.

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

• Korean Journal of Microbiology
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• v.28 no.2
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• pp.120-127
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• 1990

Intraspecific fusion frequency between Filobasidium capsuligenum CBS6122-2 ade and met trp or met strains was $2.9\times 10^{-3}$ and $8.5\times 10^{-3}$, respectively. And intergeneric fusion frequency between Folobadidium capsuligenum CBS 4318 (cys his) and Saccharomyces cerevisiae 262-12-1 (hom3 thr1) or X2180-1A (ade thr) was $8.8\times 10^{-6}$ and $9.5\times 10^{-4}$, respectively. Nuclear fusion appears to occru in fusants between intraspecies and intergenera as strongly suggested by DNA content, nuclear staining, comparison of survival rate to UV light and mitotic segregation analysis. It was also found that $\alpha$-amylase and glucoamylase activity from intraspecific hybrids was 1.6-2.1 fold increased when compared with that from thier parents.

• Journal of Mushroom
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• v.2 no.2
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• pp.109-113
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• 2004

Pleurotus eryngii is not edible and medicinal mushrooms indigenous to Korea. To improvement of strain suitable to the geographic setting of Korea, we are mated with 22 dikaryons and 47 monokaryons isolated from Pleurotus eryngii ASI 2547 by Di-Mon mating. 19 strains forming fruit body obtained from clamped 253 bred strains. 7 excellent strains are selected from 19 bred strains by various morphological features of fruit body. Among the selected 7 strains, H6 strain were identified into ASI 2547-like recombinant hybrids with URP uniprimer by RAPD analysis. This suggested that Di-Mon crossing is one of rapid and easy breeding method for strain improvement with molecular techniques.