Earticle

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 25oC and 30oC. 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.

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.

The potential ability of Button mushroom compost (BMC) to solubilize heavy metals was estimated with metal contaminated soils collected from abandoned mines of Boryeong area in South Korea. The bacterial strains in BMC were isolated for investigating the mobilization of metals in soil or plant by the strains and identified according to 16S rRNA gene sequence analysis. When metal solubilization potential of BMC was assessed in a batch experiment, the BMC was found to be capable of solubilizing metals in the presence of metals (Co, Pb and Zn) and the results showed that inoculation of BMC could increase the concentrations of water soluble Co, Pb and Cd by 35, 25 and 45% respectively, than those of non- inoculated soils. BMC-assisted growth promotion and metal uptake in sunflower (Helianthus annuus) was also evaluated in a pot experiment. In comparison with non-inoculated seedlings, the inoculation led to increase the growth of H. annuus by 27, 25 and 28% respectively in Co, Pb and Zn contaminated soils. Moreover, enhanced accumulation of Co, Pb and Zn in the shoot and root systems was observed in inoculated plants, where metal translocation from root to the above-ground tissues was also found to be enhanced by the BMC. The apparent results suggested that the BMC could effectively be employed in enhancing phytoextraction of Co, Pb and Zn from contaminated soils.

The primary objective of the present study is the characterization of the hybrids of monokaryon- monokaryon (monomono) 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.

This research was carried out to analyze the genetic variation of 18 wild strain, 2 breed varieties and 20 mutants of Hypsizygus marmoreus by random amplification of polymorphic DNA(RAPD). Also, 3 strains of Lyophyllum decartes and 1 strain of Lyophyllum shimeji were used. These mushrooms were collected from korea, china, Taiwan and Japan. Spores of H. marmoreus JV-2 strain were irradiated by gamma ray for mutagenesis. 40 kind of primers were used for this reaserch. Number of reaction primer were 31. Electrophorectic patterns of RAPD showed genetic variation. In phylogenetic tree, they were divided into seven group. Discriminative differences were observed between wild strain and mutants in H. marmoreus. These results might suggest that these primers and gamma ray irradiation of spores were useful tools for developing new strain for mushroom.

In order to breed a new P. eryngii cultivar with high temperature tolerance trait to cope with climate change, strains and cultivars were characterized at 20oC that is 5oC higher than normal condition followed by screening for the characteristics such as required days to harvest, quality and yield. Monokaryons from the selected strains were crossed. Da-32×KNR2322-15 derived from the crosses between KNR2322 having characteristics of short growing day and Da(Ga5Na5-4× KNR2312-7) having charateristics of high guality and yield at 20oC, showed 14.9 days for harvest, 120.6 g yield, and 7.0 quality in the first trial. The strains were named as Taeyangsongi and cultivated on a large scale to compare with Kenneutari No. 2 at a mushroom farm. Yield of Taeyangsongi (109 g) was significantly different(P=0.001) from Kenneutari No.2. Quality of the new (6.6) and the reference cultivar (3.5) was also statistically different (P=0.001) The brightness of pileus of Taeyangsongi (59.5) was 10 points less than the reference cultivar due to which it has an inability to bear high temperature stress. Thus, PCR reactions with URP2 discriminated between Taeyansongi and reference cultivars (Keneutari No. 2 and Aeryni).

Flammulina velutipes fruit body, Flammulina velutipes mycelium and Cordyceps militaris mycelium were analyzed for their proximate composition, protein-bound polysaccharide, nucleic acid and amino acids. The content of ash and crude fiber in F. velutipes fruit body were higher than F. mycelium and C. militaris mycelium. C. militaris mycelium showed the highest crude fat content while F. velutipes fruit body had lowest. Nitrogen free extract content of the samples varied from 56.8% in F. velutipes fruit body to 61.9% in F. velutipes mycelium. The compositions of total protein and total free sugars of protein-bound polysaccharide were found to be significant differences for all samples. Nucleic acid related compounds were identified the 5'- GMP, 5'-XMP, 5'-IMP in all samples. The content of total nucleic acids were high in the orders of F. velutipes myclial (286.71 mg%), F. velutipes fruit body(187.36 mg%) and C. militaris mycelial(76.85 mg%). The highest content of 5'-GMP was found in F. velutipes fruit body. The most nucleic acid of F. velutipes mycelial and C. militaris mycelial were the 5'-XMP. As for the analysis of total amino acids, seventeen amino acids were identified by HPLC and the major amino acid was glutamic acid in all samples. The content of total amino acids were high in the orders of F. velutipes fruit body (19,919 mg%), F. velutipes mycelium(19,018 mg%) abd C. militaris mycelium(18,965 mg%). We determined the developing new food product such as amino acid drink and amino acid containing food using extracts of Flammulina velutipes fruit body, Flammulina velutipes mycelium and Cordyceps militaris mycelium.

The separation of the bacteria inhibiting Trichoderma sp. mold, the strain causing blue mold disease that occurs frequently when cultivating mushroom while carrying out the efficient fermentation of mushroom medium, from the growth was done. In about 200 strains isolated primarily from fungus garden samples, 6 strains were secondly isolated, which had fast growth rates and a clear zone on the plate medium of SM, AM, and CM. Among the 6 strains isolated, the C-1 strain showed high enzymatic activity of cellulase, amylase, and protease, and strong antibacterial activity for the T. virens and T. harzianum, selected finally. The selected C-1 strain was identified as Paenibacillus polymyxaby the result of the identification by Bergey's Manual of Systematic Bacteriology and the analysis of the nucleotide sequence of 16S rRNA, and named as P. polymyxa CK-1. In reviewing the growth conditions of the P. polymyxa CK-1 strain, the optimum cultivation temperature was 45oC, and the optimum pH for growth was in the range of 6.0~7.0. Appropriate incubation time of P. polymyxa CK-1 for the growth inhibition of the fungus T. virens and T. harzianum was 22 to 36 hours. And the fungal growth was not observed, even when leaving two molds inoculated on each petri dishes, which were treated with 24 hour culture solution of P. polymyxa CK-1 strain for 10 days. As a result of studying the thermal stability of the antagonists produced by the P. polymyxa CK-1 strain, no mycelial growth of the two fungi was observed in the test group treated for 20 minutes at 60oC and 100oC, but mycelial growth was slightly observed in the test group treated for 20 minutes at 121oC. As aresult of reviewing the impact of the P. polymyxa CK-1 culture medium on mushroom mycelial growth, it showed no effect on a variety of mushroom mycelial growth including enoki mushroom and shiitake mushroom.

Changes in physical and chemical properties of oak sawdust were investigated by depth and time for 46 days during the fermentation process of 33 tons of the sawdust for oak mushroom cultivation. The degrees of change in the properties of the sawdust differed depending on the depth and fermentation period. Most of the physical-chemical properties except temperature and pH gradually changed during the fermentation. The temperature change was highly sensitive to the environment at the surface sawdust to 20 cm depth, while it gradually increased to the maximum 58.9oC at 40~100 cm depths in 12 days and slowly to the maximum at 150 cm depth in 24 days. The moisture content of the sawdust decreased gradually from 31% to 26.5~28.0% in 24 days. Of the chemical properties during the fermentation, pH generally rose from 5.2 to 5.6, but it decreased to 4.4~4.7 at 150 cm depth in 16 days. While the carbon content of the sawdust was 68~70% without significant change, nitrogen content increased from 0.22% to 0.25% and thus C/N ratio gradually lowered from 320 to 280. P content in the sawdust gradually increased from 0.005% to 0.022% for 46 days. Osmotic concentration of the hot water extract of the sawdust varied 41.5~44.2 mmol/kg without significant change by the depth and time. The starch particles within initial ray parenchyma cells of sawdust decreased and fungal hyphae formed on the surface of the sawdust granules and within xylem vessel cells in 35 days. The effect of the sawdust fermentation on oak mushroom cultivation needs continued research.

Studies were made to optimize the media composition in bag culture and conducted to determine the possibility of artificial cultivation of Auricularia auricula. Sawdust spawn of media composition for optimal growth were found to be oaksawdust 80%combination of 20% popla-sawdust were the best of the optimal combination. And optimal substrate combination were found to be cotton-seed meal combination of 10% wheat bran 5% mixed were the best of combination. The duration of spawn run period and primordial formation period on bag(1.2 kg) were 50 days and 7 days, respectively. The weight of fruiting body and the yield(100ea, 1.2 kg) of fresh fruit-body were 24 g and 45,000 g, respectively.

This study was conducted to set the proper sterilization standards of casing soil for the stable production of button mushroom(Agaricus bisporus) from mushroom disease that occurs in infection of casing soil material. Changes of aerobic bacteria are increased as the longer grow-out period and sharply increased after second flushes. Fluorescence Psuedomonas showed high density at high sterilization temperature and 100oC treatment has extremely high density at 30 min and 60 min in casing 22 days. Density of thermophilic actinomyces is sharply increase from casing with soil and the highest density at 22 days of casing and rapidly decrease after first flushes. Sterilizing temperature of casing soil affects quality and quantity of button mushroom. Treatment of 60 min, 90 min at 80oC and 30 min at 100oC produced the highest mushroom yields, especially mushrooms yields of A grads were the highest at treatment of 90 min at 80oC. Treatment of 60min at 100oC products many yields, however, this treatment has low economic feasibility for its yields. Sterilizing temperature of casing soil has an effect on generating diseases and insect pests. Treatment of 60 min, 90 min at 80oC and 30 min 100oC showed lower incidence than the other treatment. Although treatment of 30 min at 100oC causes low diseases and mushroom fly damage, it has low mushroom yields. Furthermore, although treatment of 60 min at 100oC has high mushroom yields, it causes high diseases and mushroom fly damage. Therefore the best conditions for the sterilization of casing soils was 60 min and 90 min at 80oC.

In this study, SCAR marker that differentiates Pleurotus eryngii strains adaptable to high-temperature from control strain was developed. Genomic DNAs of 7 control strains of Pleurotus eryngii and 7 Pleurotus eryngii strains adaptable to hightemperature were analyzed by bulked segregant analysis (BSA) using randomly amplified polymorphic DNA (RAPD). Onehundred twenty RAPD primers were screened on bulked DNA samples and a unique DNA fragment with the size of 385 bp was yielded by OP-A06 primer from the Pleurotus eryngii strains adaptable to high- temperature. A sequence characterized amplified region (SCAR) marker, designated as OP-A06-1-F and OP-A06-1-R, was designed on the basis of the determined sequence. The PCR analysis with the OP-A06-1 primer showed that this SCAR marker can clearly distinguish the Pleurotus eryngii strains adaptable to high-temperature from the control strains.

This study was carried out to investigated optimum mixing ratio of Korean natural Rhus verniciflua for production of functional oyster mushroom. Mycerial growth was some fast at addition of R. verniciflua sawdust, and not significant difference by increase of R. verniciflua substrate. Yields of fruiting body show the highest to 150.2 g/850 ml of medium which are addition 20% of R. verniciflua sawdust, and diameter of pileus and thick of stipes were the highest at addition 10% of R. verniciflua sawdust. The L value of stipes were the highest at addition 10% of R. verniciflua sawdust and the L value of pileus were decreased by increase of R. verniciflua substrate, but there was no significant difference in the a- value and the b-value.