Oyster mushrooms including of P. ostreatus, P. eryngii, P. pulmonarius and P. cornucopiae are one of the famous mushrooms for foods in Korea. RAPD were carried out using 14 of oligoprimers to analyze the phylogenetic relationship among 57 strains of 32 Pleurotus species. Most of species formed the minimum clade with strains within species and was divided respectively species. Therefore clade was separated well in accordance species. Pleurotus species formed again clade to be added in close related to other species, and were discriminated by sixteen clades with each representative species including high similarity groups. Sixteen clades were composed representative species according to each clade. There were clade I of P. pulmonarius(P. sajor-caju, P. opuntiae, P. sapidus), clade II of P. eryngii(P. fuscus var. ferulae, P. fossulatus), clade III of P. ostreatus(P. ostreatus var. columbinus, P. spodoleucus, P. floridanus), clade IV of P. florida, clade V of P. djamor(P. flabellatus, P. incarnates, P. salmoneo-stramineus), clade VII of P. populinus(P. subareolatus), clade VIII of P. cystidiosus(P. cystidiosus var. formosensis), clade X of P. dryinus(P. dryinus var. pometi), clade XIV of P. cornucopiae(P. citrinopilieatus, P. euosmus), and clade XV of P. australis. These species were representative species each clades. Five species, P. ulmarius(clade VI), P. griseus(clade IX), P. calyptratus(clade XI), P. lampas(clade XII), P. smithii(clade XIII)and P. serotinus (clade XVI) were used each one strain in analysis, so they were clustered other groups.

Pleurotus has increased rapidly production and consumption because of highly nutritional value, natural healthy food and so on. The basic studies for Pleurotus need for development of mushroom industry. This study was to investigate the cultural characteristics among 15 strains of 6 species and to analyze their phylogenetic relationships. The cultural characteristics were investigated by mycelial growth activity at different media, temperature and pH. The optimum media for mycelial growth were YM and MCM in most species. The optimum temperature for mycelial growth were 25˚C and 30˚C. The optimum pH for mycelial growth were widly range from pH 5.1 to 7.4. Through the RFLP (restriction fragment length polymorphism) of IGS (intergenic spacer) I region in ribosomal DNA, it was analyzed phylogeny of interspecies and intraspecies. Each species was discriminated well as isolates within each species formed clade to be distinguished other species. P. florida was highly similar to P. floridanus, and P. flabellatus was P. cornucopiae. P. fuscus var. ferulae was highly similar to P. eryngii but discriminated different species in analysis of RFLP of IGS I region and showed different characteristics in mycelial culture. RFLP of IGS I region was useful of studying phylogenetic relationships of species and population.

Sperm chromatin integrity is essential for successful fertilization and development of an embryo. Reported here is a quantification of DNA fragments which is intimately associated with reproductive potential to provide one of criteria for sperm chromatin integrity. Three sperm populations were considered: CONTROL (no treatment), UV irradiation (48mW/, 1h) and (oxidative stress induced by hydrogen peroxide, 10 mM, 50 mM and 100 mM). DNA fragments in boar sperm were evaluated by using ligation-mediated quantitative real-time polymerase chain reaction (LM-qPCR) assay, which relies on real-time qPCR to provide a measure of blunt 5' phosphorylated double strand breaks in genomic DNA. The results in agarose gel electrophoresis showed no significant DNA fragmentation and no dose-dependent response to . However, the remarkable difference in shape and position was observed in melting curve of LM-qPCR. This result supported that the melting curve analysis of LM-qPCR presented here, could be more sensitive and accurate than previous DNA fragmentation assay method.

Sex-sorting of sperm is an assisted reproductive technology (ART) used by the livestock industry for the mass production of animals of a desired sex. The standard method for sorting sperm is the detection of DNA content differences between X and Y chromosome-bearing sperm by flow cytometry. However, this method has variable efficiency and therefore requires verification by a second method. We have developed a sex determination method based on quantitative real-time polymerase chain reaction (qPCR) of the porcine amelogenin (AMEL) gene. The AMEL gene is present on both the X and the Y chromosome, but the length and sequence of its noncoding regions differ between the X and Y chromosomes. By measuring the threshold cycle (Ct) of qPCR, we were able to calculate the relative frequency of X chromosome. Two sets of AMEL primers were used in these studies. One set (AME) targeted AMEL gene sequences present in both X and Y chromosome, but produced PCR products of different lengths for each chromosome. The other set (AXR) bound to AMEL gene sequences present on the X chromosome but absent esholthe Y-chromosome. Relative product levels were calculated by normalizing the AXR fluorescence to the AME fluorescence. The AMEL method accurately predicted the sex ratios of boar sperm, demonstrating that it has potential value as a sex determination method.