Fruiting Body Initiation Research Articles

Pengaruh Media Tanam Campuran Serbuk Bambu dan Serbuk Kayu Terhadap Pertumbuhan dan Hasil Jamur Tiram (Pleurotus ostreatus)

Oyster mushroom is a commodity that is in high demand in the community. Oyster mushroom production in Indonesia is decreasing year after year as wood sawdust, which is often used as a media for oyster mushrooms, becomes increasingly difficult to get. Bamboo has a nutrient content similar to wood sawdust; therefore, bamboo sawdust can be utilized as a media for growing oyster mushrooms. The aim of this research was to find the best mixture of bamboo and wood sawdust for the growth and yield of oyster mushrooms (Pleurotus ostreatus). This research was carried out from July to October 2023 at Lampung State Polytechnic. This study used a randomized block design with one factor that was repeated four times. The following treatments were used: C0 = 100% wood sawdust, C1 = 90% bamboo sawdust + 10% wood sawdust, L2 = 80% bamboo sawdust + 20% wood sawdust, C3 = 70% bamboo sawdust + 30% wood sawdust, C4 = 60% bamboo sawdust + 40% wood sawdust, and C5 = 50% bamboo sawdust + 50% wood sawdust. The collected data was analyzed using analysis of variance (ANOVA) and then evaluated with LSD test at the 5% level. The results of this research were that the treatment of C5 = 50% bamboo sawdust + 50% wood sawdust gave the best results on the parameter of the mycelium growth rate, the time of the fruit body initiation (FBI), the number of hoods, the diameter of the hood, the thickness of the hood, the harvest, the harvest weight per baglog, and the total harvesting per plot.

Transcriptome Analysis Reveals Mycelial and Fruiting Responses to Lithium Chloride in Coprinopsis cinerea.

Lithium chloride (LiCl) has been used in signalling and molecular studies of animals, plants, and yeast. However, information on its roles in basidiomycetous fungi is still limited. In this study, we used RNA-Seq to study the effects of LiCl on Coprinopsis cinerea. LiCl enhanced mycelial growth and inhibited fruiting body formation in C. cinerea. RNA-Seq of the LiCl-treated C. cinerea resulted in a total of 14,128 genes. There were 1199 differentially expressed genes (DEGs) between the LiCl-treated samples and control samples in the mycelium stage (the first time point), and 1391 DEGs were detected when the control samples were forming hyphal knots while the treated samples were still in the mycelium (the second time point). Pathway enrichment analysis of the DEGs revealed a significant association between enhanced mycelium growth in the LiCl-treated C. cinerea and metabolic pathways. In addition, the DEGs involved in cellular process pathways, including "cell cycle-yeast" and "meiosis-yeast", were identified in suppressed C. cinerea fruiting body formation by LiCl under favourable environmental conditions. As LiCl can predominantly inhibit the activity of glycogen synthase kinase3 (GSK3), our findings suggest that LiCl affects the expression of genes involved in fruiting body initiation and cellular processes by inhibiting GSK3 activity which is essential for fruiting body formation.

Transcriptome and metabonomics combined analysis revealed the energy supply mechanism involved in fruiting body initiation in Chinese cordyceps

Chinese cordyceps was one of most valuable traditional Chinese medicine fungi. To elucidate the molecular mechanisms related to energy supply mechanism involved in the initiation and formation of primordium in Chinese cordyceps, we performed the integrated metabolomic and transcriptomic analyses of it at pre-primordium period, primordium germination period and after-primordium period, respectively. Transcriptome analysis showed that many genes related to ‘starch and sucrose metabolism’, ‘fructose and mannose metabolism’, ‘linoleic acid metabolism’, ‘fatty acids degradation’ and ‘glycerophospholipid metabolism’ were highly up-regulated at primordium germination period. Metabolomic analysis showed many metabolites regulated by these genes in these metabolism pathways were also markedly accumulated at this period. Consequently, we inferred that carbohydrate metabolism and β-oxidation pathway of palmitic acid and linoleic acid worked cooperatively to generate enough acyl-CoA, and then entered TCA cycle to provide energy for fruiting body initiation. Overall, our finding provided important information for further exploring the energy metabolic mechanisms of realizing the industrialization of Chinese cordyceps artificial cultivation.

Oxidative Stress and Autophagy Are Important Processes in Post Ripeness and Brown Film Formation in Mycelium of Lentinula edodes.

Lentinula edodes (Berk.) Pegler, the shiitake mushroom, is one of the most important mushrooms in the global mushroom industry. Although mycelium post ripeness and brown film (BF) formation are crucial for fruiting body initiation, the underlying molecular mechanisms of BF formation are largely unknown. In this study, proteomic quantification (relative and absolute) and metabolomic profiling of L. edodes were performed using isobaric tags and gas chromatography-mass spectroscopy, respectively. A total of 2,474 proteins were identified, which included 239 differentially expressed proteins. Notably, several proteins associated with autophagy were upregulated, including RPD3, TOR1, VAC8, VPS1, and VPS27. Transmission electron microscopy also indicated that autophagy occurred in post ripeness and BF formation. In time-dependent analysis of the metabolome, metabolites associated with oxidative stress and autophagy changed significantly, including mannitol, trehalose, myo-inositol, glucose, leucine, valine, glutamine, and 4-aminobutyric acid. Thus, oxidative stress and autophagy were important processes in post ripeness and BF formation in L. edodes, and new insights were gained into molecular mechanisms at proteome and metabolome levels.

ITRAQ-based comparative proteome analyses of different growth stages revealing the regulatory role of reactive oxygen species in the fruiting body development of Ophiocordyceps sinensis.

In this study, using an isobaric tags for relative and absolute quantitation (iTRAQ ) approach coupled with LC-MS / MS and bioinformatics, the proteomes were analyzed for the crucial three stages covering the fruiting body development of Ophiocordyceps sinensis, including sclerotium (ST), primordium (PR) and mature fruiting body (MF), with a focus on fruiting body development-related proteins and the potential mechanisms of the development. A total of 1,875 proteins were identified. Principal Component Analysis (PCA) demonstrated that the protein patterns between PR and MF were more similar than ST. Differentially accumulated proteins (DAPs) analysis showed that there were 510, 173 and 514 DAPs in the comparisons of ST vs. PR, PR vs. MF and ST vs. MF, respectively. A total of 62 shared DAPs were identified and primarily enriched in proteins related to ‘carbon transport and mechanism’, ‘the response to oxidative stress’, ‘antioxidative activity’ and ‘translation’. KEGG and GO databases showed that the DAPs were enriched in terms of ‘primary metabolisms (amino acid/fatty acid/energy metabolism)’, ‘the response to oxidative stress’ and ‘peroxidase’. Furthermore, 34 DAPs involved in reactive oxygen species (ROS) metabolism were identified and clustered across the three stages using hierarchical clustering implemented in hCluster R package . It was suggested that their roles and the underlying mechanisms may be stage-specific. ROS may play a role in fungal pathogenicity in ST, the fruit-body initiation in PR, sexual reproduction and highland adaptation in MF. Crucial ROS-related proteins were identified, such as superoxide dismutase (SOD, T5A6F1), Nor-1 (T5AFX3), electron transport protein (T5AHD1), histidine phosphotransferase (HPt, T5A9Z5) and Glutathione peroxidase (T5A9V1). Besides, the accumulation of ROS at the three stages were assayed using 2,7-dichlorofuorescin diacetate (DCFH-DA) stanning. A much stronger ROS accumulation was detected at the stage MF, compared to the stages of PR and ST. Sections of ST and fruit-body part of MF were stained by DCFH-DA and observed under the fluorescencemicroscope, showing ROS was distributed within the conidiospore and ascus. Besides, SOD activity increased across the three stages, while CAT activity has a strong increasement in MF compared to the stages of ST and PR. It was suggested that ROS may act in gradient-dependent manner to regulate the fruiting body development. The coding region sequences of six DAPs were analyzed at mRNA level by quantitative real-time PCR (qRT-PCR). The results support the result of DAPs analysis and the proteome sequencing data. Our findings offer the perspective of proteome to understand the biology of fruiting body development and highland adaptation in O. sinensis, which would inform the big industry of this valuable fungus.

Comparative genomics of pyrophilous fungi reveals a link between fire events and developmental genes.

Forest fires generate a large amount of carbon that remains resident on the site as dead and partially 'pyrolysed' (i.e. burnt) material that has long residency times and constitutes a significant pool in fire-prone ecosystems. In addition, fire-induced hydrophobic soil layers, caused by condensation of pyrolysed waxes and lipids, increase post-fire erosion and can lead to long-term productivity losses. A small set of pyrophilous fungi dominate post-fire soils and are likely to be involved with the degradation of all these compounds, yet almost nothing is currently known about what these fungi do or the metabolic processes they employ. In this study, we sequenced and analysed genomes from fungi isolated after Rim fire near Yosemite National Park in 2013 and showed the enrichment/expansion of CAZymes and families known to be involved in fruiting body initiation when compared to other basidiomycete fungi. We found gene families potentially involved in the degradation of the hydrophobic layer and pyrolysed organic matter, such as hydrophobic surface binding proteins, laccases (AA1_1), xylanases (GH10, GH11), fatty acid desaturases and tannases. Thus, pyrophilous fungi are important actors to restate the soil's functional capabilities.

Transcriptomic analysis of the orchestrated molecular mechanisms underlying fruiting body initiation in Chinese cordyceps.

Chinese cordyceps, the fruiting body of the Chinese caterpillar fungus (Ophiocordyceps sinensis, syn. Cordyceps sinensis), is among the most valuable traditional Chinese medicine fungi. Transcriptomic analysis of O. sinensis has revealed several aspects of its life cycle and ecological importance. However, the molecular mechanisms involved in fruiting body initiation remain unclear. The developmental transcriptomes were analyzed from three tissues at the fruiting body initiation stage, namely, the mycelium, sclerotium and primordium. Principal component analysis showed that in the three tissues, the gene expression patterns differed from each other. The functional analysis of differentially expressed genes showed that DNA synthesis and cell division were active in the primordium. In addition, the function of the mycelium was to absorb certain substances from the environment and the sclerotium was the metabolism center of O. sinensis. Genes participating in the mitogen-activated protein kinase (MAPK) signal pathway were involved in fruiting body initiation. Two environmental sensing genes, including a pheromone receptor gene (OSIN6252) and an amino acid sensing gene (OSIN6398), were highly expressed in the primordium, suggesting their important roles in initiation. These results provided insights into the orchestrated functions and gene profiles of different O. sinensis tissues at the key stage. These findings will aid in revealing the underlying mechanisms of fruiting body initiation, which will further benefit artificial cultivation.

Seeking the Roles for Fungal Small-Secreted Proteins in Affecting Saprophytic Lifestyles.

Small secreted proteins (SSPs) comprise 40–60% of the total fungal secretome and are present in fungi of all phylogenetic groups, representing the entire spectrum of lifestyles. They are characteristically shorter than 300 amino acids in length and have a signal peptide. The majority of SSPs are coded by orphan genes, which lack known domains or similarities to known protein sequences. Effectors are a group of SSPs that have been investigated extensively in fungi that interact with living hosts, either pathogens or mutualistic systems. They are involved in suppressing the host defense response and altering its physiology. Here, we aim to delineate some of the potential roles of SSPs in saprotrophic fungi, that have been bioinformatically predicted as effectors, and termed in this mini-review as “effector-like” proteins. The effector-like Ssp1 from the white-rot fungus Pleurotus ostreatus is presented as a case study, and its potential role in regulating the ligninolytic system, secondary metabolism, development, and fruiting body initiation are discussed. We propose that deciphering the nature of effector-like SSPs will contribute to our understanding of development and communication in saprophytic fungi, as well as help, to elucidate the origin, regulation, and mechanisms of fungal-host, fungal-fungal, and fungal-bacterial interactions.

Effect of ground temperature on Tricholoma matsutake fruiting body initiation in the inland region of Iwate Prefecture, Japan

Effect of ground temperature on <i>Tricholoma matsutake</i> fruiting body initiation in the inland region of Iwate Prefecture, Japan

Discussion of development processes in insect-fungus association derived from the shaggy parasol fruiting on the nests of hairy wood ants.

Chlorophyllum rhacodes, typically regarded as a rich grassland or open forest “mushroom” species, was found fruiting abundantly on nests of Formica lugubris, occurring in a Pinus silvestris plantation. Fruiting was absent from the rest of the woodland.Research focussed on the activities in the nests that could explain this. Within nests, there was a spatial relationship between C. rhacodes mycelium, insect cadavers, fruitbody initiation, and roots of adjacent trees.In vitro experiments found that C. rhacodes was not mycorrhizal with P. silvestris, but that it had qualities which rendered it suitable for colonization of the rhizosphere in the conditions of the nest mound and for further niche development.Implications of the unusual presence of fruit‐bodies and the distribution of associated hyphae are discussed in relation to the nutritional biology (and recent taxonomical reassignment) of the fungus. This includes reference to the relevant physiology of insects and to the accepted evolution of mutualistic symbioses between fungi and the Attini and Termitidae.An argument is presented that the situation observed in vivo provides evidence of a degree of facultative association and what could be tangible support for the theory for the developmental origin of mutualistic fungus cultivation by insects. It is presented as a context for continued experimental research.

Manipulating the Expression of Small Secreted Protein 1 (Ssp1) Alters Patterns of Development and Metabolism in the White-Rot Fungus Pleurotus ostreatus.

The function of small secreted proteins (SSPs) in saprotrophic fungi is, for the most part, unknown. The white-rot mushroom Pleurotus ostreatus produces considerable amounts of SSPs at the onset of secondary metabolism, during colony development, and in response to chemical compounds such as 5-hydroxymethylfurfural and aryl alcohols. Genetic manipulation of Ssp1, by knockdown (KDssp1) or overexpression (OEssp1), indicated that they are, in fact, involved in the regulation of the ligninolytic system. To elucidate their potential involvement in fungal development, quantitative secretome analysis was performed during the trophophase and the idiophase and at a transition point between the two growth phases. The mutations conferred a time shift in the secretion and expression patterns: OEssp1 preceded the entrance to idiophase and secondary metabolism, while KDssp1 was delayed. This was also correlated with expression patterns of selected genes. The KDssp1 colony aged at a slower pace, accompanied by a slower decline in biomass over time. In contrast, the OEssp1 strain exhibited severe lysis and aging of the colony at the same time point. These phenomena were accompanied by variations in yellow pigment production, characteristic of entrance of the wild type into idiophase. The pigment was produced earlier and in a larger amount in the OEssp1 strain and was absent from the KDssp1 strain. Furthermore, the dikaryon harboring OEssp1 exhibited a delay in the initiation of fruiting body formation as well as earlier aging. We propose that Ssp1 might function as a part of the fungal communication network and regulate the pattern of fungal development and metabolism in P. ostreatusIMPORTANCE Small secreted proteins (SSPs) are common in fungal saprotrophs, but their roles remain elusive. As such, they comprise part of a gene pool which may be involved in governing fungal lifestyles not limited to symbiosis and pathogenicity, in which they are commonly referred to as "effectors." We propose that Ssp1 in the white-rot fungus Pleurotus ostreatus regulates the transition from primary to secondary metabolism, development, aging, and fruiting body initiation. Our observations uncover a novel regulatory role of effector-like SSPs in a saprotroph, suggesting that they may act in fungal communication as well as in response to environmental cues. The presence of Ssp1 homologues in other fungal species supports a common potential role in environmental sensing and fungal development.

Comparative transcriptome analysis identified candidate genes involved in mycelium browning in Lentinula edodes

BackgroundLentinula edodes is one of the most popular edible mushroom species in the world and contains useful medicinal components, such as lentinan. The light-induced formation of brown film on the vegetative mycelial tissues of L. edodes is an important process for ensuring the quantity and quality of this edible mushroom. To understand the molecular mechanisms underlying this critical developmental process in L. edodes, we characterized the morphological phenotypic changes in a strain, Chamaram, associated with abnormal brown film formation and compared its genome-wide transcriptional features.ResultsIn the present study, we performed genome-wide transcriptome analyses of different vegetative mycelium growth phenotypes, namely, early white, normal brown, and defective dark yellow partial brown films phenotypes which were exposed to different light conditions. The analysis revealed the identification of clusters of genes specific to the light-induced brown film phenotypes. These genes were significantly associated with light sensing via photoreceptors such as FMN- and FAD-bindings, signal transduction by kinases and GPCRs, melanogenesis via activation of tyrosinases, and cell wall degradation by glucanases, chitinases, and laccases, which suggests these processes are involved in the formation of mycelial browning in L. edodes. Interestingly, hydrophobin genes such as SC1 and SC3 exhibited divergent expression levels in the normal and abnormal brown mycelial films, indicating the ability of these genes to act in fruiting body initiation and formation of dikaryotic mycelia. Furthermore, we identified the up-regulation of glycoside hydrolase domain-containing genes in the normal brown film but not in the abnormal film phenotype, suggesting that cell wall degradation in the normal brown film phenotype is crucial in the developmental processes related to the initiation and formation of fruiting bodies.ConclusionsThis study systematically analysed the expression patterns of light-induced browning-related genes in L. edodes. Our findings provide information for further investigations of browning formation mechanisms in L. edodes and a foundation for future L. edodes breeding.

The intensity of blue light-emitting diodes influences the antioxidant properties and sugar content of oyster mushrooms (Lentinus sajor-caju)

In this study, we examined the influences of four light intensities on mushroom biomass and effects of a blue (B) light-emitting diode (LED) source with 10–40μmolm−2s−1 of photosynthetic photon flux density (PPFD) on the antioxidant capacity and soluble sugar content of the edible oyster mushroom L. sajor-caju Fr. which is popularly cultivated in Taiwan. Fruiting body initiation and development of mushrooms cultivated on blocks made of sawdust, rice-bran, and wheat-bran media were carried out with an 8-h photoperiod at 26°C and 85% relative humidity under LEDs lights inside growth chambers. When the basidiome has began development, mushroom blocks containing primordia were exposed to different light conditions for 7days. Results showed that B-LED PPFD of mushrooms significantly promoted the accumulation of dry biomass. This study explored the relationship between the light intensity of B-LED and antioxidant properties. Different light intensities variably affected the antioxidant system of the mushroom, and higher light intensities resulted in an increased DPPH radical-scavenging effect, Fe-chelating ability, and reducing power. In addition, 40 PPFD of the B-light source caused greater accumulation of soluble sugars than other B-light intensities. Precise management of B light may hold promise in promoting the nutritional value of edible mushrooms cultivated in controlled environments with future utilization of LEDs on an industrial scale.

Mechanism of Glucose Regulates the Fruiting Body Formation in the Beech Culinary-Medicinal Mushroom, Hypsizygus marmoreus (Agaricomycetes).

To understand the fruiting process of Hypsizygus marmoreus, a synthetic liquid medium (SLM) was optimized to induce fruiting body initiation. Dependent on the SLM, the effect of a monofactor (glucose) on the fruiting bodies of H. marmoreus was studied at different concentrations (10 and 40 g/L). Primordia appeared approximately 10 days earlier in low-glucose media (LGM) than in high-glucose media (HGM), whereas mature fruiting bodies formed on mushrooms approximately 7 days earlier and more primordia developed into mature fruiting bodies when cultured in HGM. In addition, the morphogenesis of the primordia was clustered in HGM, which was different than what was observed in LGM. Furthermore, differentially expressed genes (DEGs) that encoded various proteins involved in cell structure, general metabolism, signal transduction, and transcription and translation were analyzed by transcriptome sequencing. Six DEGs were detected by quantitative reverse-transcriptase polymerase chain reaction, and the results were consistent with the altered patterns of gene expression revealed by the transcriptome. This study not only identifies new candidate genes involved in the development of H. marmoreus but also provides a new research platform for studying the development of other edible mushrooms.

고온성 백색 팽이버섯 '백중' 육성경과 및 품종 특성

‘Baekjung’ adaptable to high temperature was made by crossing between monokaryon derived from selfing of brown strain and monokaryon derived from Korea white strain. In the condition that temperature is maintained at 10oC without low temperature of 4oC suppressing treatment and wrapping during cultivation period, it showed good productivity than Uri1ho(control). The optimum temperature of mycelial growth was 30oC and that of fruiting body initiation and development were 14oC and 7oC, respectively. The days for the fruiting and yield were 7 days and 277±11.2 g per 1,100 ml bottle, respectively. This variety needed high concentration of carbon dioxide up to 4,000 ppm for the good quality.

Cloning and functional analysis of a laccase gene during fruiting body formation in Hypsizygus marmoreus

The Hypsizygus marmoreus laccase gene (lcc1) sequence was cloned and analyzed. The genomic DNA of lcc1 is 2336bp, comprising 13 introns and 14 exons. The 1626-bp full-length cDNA encodes a mature laccase protein containing 542 amino acids, with a 21-amino acid signal peptide. Phylogenetic analysis showed that the lcc1 amino acid sequence is homologous to basidiomycete laccases and shares the highest similarity with Flammulina velutipes laccase. A 2021-bp promoter sequence containing a TATA box, CAAT box, and several putative cis-acting elements was also identified. To study the function of lcc1, we first overexpressed lcc1 in H. marmoreus and found that the transgenic fungus producing recombinant laccase displayed faster mycelial growth than the wild-type (wt) strain. Additionally, primordium initiation was induced 3–5 days earlier in the transgenic fungus, and fruiting body maturation was also promoted approximately five days earlier than in the wt strain. Furthermore, we detected that lcc1 was sustainably overexpressed and that laccase activity was also higher in the transgenic strains compared with the wt strain during development in H. marmoreus. These results indicate that the H. marmoreus lcc1 gene is involved in mycelial growth and fruiting body initiation by increasing laccase activity.

Transcriptome analysis and its application in identifying genes associated with fruiting body development in basidiomycete Hypsizygus marmoreus.

To elucidate the mechanisms of fruit body development in H. marmoreus, a total of 43609521 high-quality RNA-seq reads were obtained from four developmental stages, including the mycelial knot (H-M), mycelial pigmentation (H-V), primordium (H-P) and fruiting body (H-F) stages. These reads were assembled to obtain 40568 unigenes with an average length of 1074 bp. A total of 26800 (66.06%) unigenes were annotated and analyzed with the Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology (GO), and Eukaryotic Orthologous Group (KOG) databases. Differentially expressed genes (DEGs) from the four transcriptomes were analyzed. The KEGG enrichment analysis revealed that the mycelium pigmentation stage was associated with the MAPK, cAMP, and blue light signal transduction pathways. In addition, expression of the two-component system members changed with the transition from H-M to H-V, suggesting that light affected the expression of genes related to fruit body initiation in H. marmoreus. During the transition from H-V to H-P, stress signals associated with MAPK, cAMP and ROS signals might be the most important inducers. Our data suggested that nitrogen starvation might be one of the most important factors in promoting fruit body maturation, and nitrogen metabolism and mTOR signaling pathway were associated with this process. In addition, 30 genes of interest were analyzed by quantitative real-time PCR to verify their expression profiles at the four developmental stages. This study advances our understanding of the molecular mechanism of fruiting body development in H. marmoreus by identifying a wealth of new genes that may play important roles in mushroom morphogenesis.

Antioxidant Potential of Lingzhi or Reishi Medicinal Mushroom, Ganoderma lucidum (Higher Basidiomycetes) Cultivated on Artocarpus heterophyllus Sawdust Substrate in India.

The artificial cultivation of Ganoderma lucidum (MTCC1039) using Artocarpus heterophyllus as sawdust substrate was optimized and free radical scavenging activities of the generated fruiting bodies were investigated. The choice of A. heterophyllus as substrate was due to its easy availability in South India. Sawdust supplemented with dextrose medium yielded better spawn hyphae and early fruiting body initiation (15 days). The biological yield obtained was 42.06 ± 2.14 g/packet and the biological efficiency was 8.41 ± 0.48%. Both aqueous and methanolic extracts of fruiting body were analyzed for radical scavenging activity. Methanolic extract showed maximum scavenging activity for 1,1-diphenyl-2-picrylhydrazyl (IC50 = 290 μg/ml) and 2,2'-azino-bis(3-ethylbenzothiazoline- 6-sulphonic acid (IC50 = 580 μg/ml), whereas aqueous extract had better scavenging for ferric reducing antioxidant power (IC50 = 5 μg/ml). Total phenolic content and total antioxidant capacity were significantly higher in methanolic extract (p < 0.01). A positive correlation existed between the phenolic content and antioxidant activity. Our results indicated that fruiting bodies of G. lucidum cultivated in sawdust medium possess antioxidant property, which can be exploited for therapeutic application.

Differential response of oyster shell powder on enzyme profile and nutritional value of oyster mushroom Pleurotus florida PF05.

Oyster mushroom Pleurotus florida was cultivated on different combinations of wheat straw (WS) as basal substrate and oyster shell powder (OSP) supplement. The OSP supplementation considerably responded to different cultivation phases. The mycelium grew fast and showed rapid growth rate (8.91 mmd−1) in WS + OSP (97 + 3) combination while WS + OSP (92 + 8) showed maximum laccase (3.133 U/g) and Mn peroxidase (MnP) activities (0.091 U/g). The climax level of laccase (5.433 U/g) and MnP (0.097 U/g) was recorded during fruit body initiation in WS + OSP (97 + 3) and WS + OSP (98 + 2) combinations, respectively. The WS + OSP (97 + 3) combination represented the best condition for mushroom cultivation and produced the highest biological efficiency (147%). In addition, protein and lipid contents in fruit bodies were slightly improved in response to OSP. The carbohydrate was significantly increased by raising concentration of OSP. The highest values of protein, carbohydrate, and lipid noted were 31.3 μg/g, 0.0639 (g/g), and 0.373 (g/g) correspondingly. Conclusively it was evident that lower concentrations of OSP acted positively and relatively to higher concentrations and improved nutritional content which may suitably be used to enhance both yield and nutritional values of mushroom.

한국형 백색 팽이버섯 '백아' 육성경과 및 품종 특성

We made the first Korean white commercial strain `Baek-a` developed by crossing between monokaryons derived from brown strains. This variety can be estimated as the Korea`s indigenous one different from the origin of Japanese white ones. The optimum temperature of mycelial growth was but it needed to adjust to when incubated at the bottle cultivation. The optimum temperatures of fruiting body initiation and development were and , respectively. Fruiting body of `Baek-a` was pure white even developed from crossing with brown strains. `Baek-a` was a good variety with high quality and high productivity characterized as quite even budding habit, long stipes and hemi-spherical pilei. The days for the fruiting was 7 days and the productivity was g per 850 ml. This variety needed high concentration of carbon dioxide and it had to be adjusted up to 4,000 ppm for the good quality.