Fruiting Body Formation Research Articles

Qualitative characteristics of the fungus Cyclocybe aegerita strains 2229, 2230, 2231 IBK under industrial cultivation conditions

Poplar mushroom is characterised by attractive fruiting bodies in terms of appearance and taste. Cyclocybe aegerita mushrooms are also known to contain unique substances, including proteins, polysaccharides, and aromatic substances with proven nutritional value and medicinal effects. However, the lack of a sound cultivation technology using available plant material limits the saturation of the domestic market with mushrooms of this species. Three strains of C. aegerita from the IBK National Collection of Agaricale Cultures of the Institute of Ecology and Natural Resources were studied for their potential introduction into commercial culture. It was determined that strains 2230 and 2231 have a vegetation cycle of 42 days compared to 46-64 days for the previously studied strains. The highest yield in the experiment was obtained for strain 2231, which ranged from 217 to 220 g per kilogram of a substrate over three cultivation cycles. The biological efficiency of the strains according to the results of the first wave of fruiting ranged from 20.2 (2229) to 60.4% (2231), which is consistent with the published data of other researchers. The appearance and parameters of the fruiting bodies of the strains, which differed in both the colour of the pileus and the size, were described in detail. Under microclimatic conditions of the experiment, strains 2230 and 2231 had a rich brown colour of pilei, while the formed fruit bodies of strain 2229 were distinguished by a pleasant milky cream colour. The largest fruiting bodies in terms of weight were obtained by cultivation of strain 2229 (7.5 ± 0.4 g), which is on average 2 g higher than the weight of mushrooms of other studied strains. The highest fruiting bodies were discovered in strain 2230 having a height of 91.0 ± 1.8 mm, which also had the widest pilei with a diameter of 29.5 ± 0.9 mm. The largest stem diameter, which reached an average of 10.8 ± 0.3 mm, was detected in the fruiting bodies of strain 2229. This study investigated the variability of morphological traits and identified trends in the number of fruiting bodies of a certain size in the total volume of collected mushrooms, which facilitates the design of packaging and marketing campaigns

Functional characterization of the developmental genes asm2, asm3, and spt3 required for fruiting body formation in the filamentous ascomycete Sordaria macrospora.

The formation of fruiting bodies is one of the most complex developmental processes in filamentous ascomycetes. It requires the development of sexual structures that give rise to meiosporangia (asci) and meiotic spores (ascospores) as well as surrounding structures for protection and dispersal of the spores. Previous studies have shown that these developmental processes are accompanied by significant changes of the transcriptome, and comparative transcriptomics of different fungi as well as the analysis of transcriptome changes in developmental mutants have aided in the identification of differentially regulated genes that are themselves involved in regulating fruiting body development. In previous analyses, we used transcriptomics to identify the genes asm2 and spt3, which result in developmental phenotypes when deleted in Sordaria macrospora. In this study, we identified another gene, asm3, required for fruiting body formation, and performed transcriptomics analyses of Δasm2, Δasm3, and Δspt3. Deletion of spt3, which encodes a subunit of the SAGA complex, results in a block at an early stage of development and drastic changes in the transcriptome. Deletion mutants of asm2 and asm3 are able to form fruiting bodies, but have defects in ascospore maturation. Transcriptomics analysis of fruiting bodies revealed a large overlap in differentially regulated genes in Δasm2 and Δasm3 compared to the wild type. Analysis of nuclear distribution during ascus development showed that both mutants undergo meiosis and postmeiotic divisions, suggesting that the transcriptomic and morphological changes might be related to defects in the morphogenesis of structural features of the developing asci and ascospores.

Lignolytic enzymes (laccase and peroxidase) production by pink oyster mushroom, Pleurotus djamor

This research work attempts the use of biogas digester liquid (BDL) as an inducer for lignolytic enzyme activity by Pleurotus djamor when grown in SSF culture condition. BDL rich in polyphenols and micronutrients can induce lignin degrading enzymes such as laccase and peroxidase. Spraying 100 ml BDL/bag (1kg paddy straw)/day was found to increase yields of Pleurotus djamor in SSF and also reduced the time for various stages of mushroom growth such as pin head formation, fruiting body formation and first flush by 3-5d. Of the 100ml BDL sprayed 70ml was collected as leachate and this showed highlignolytic enzyme (Laccase 150 U/L and Peroxidase 160U/L) activities in SSF and the enzyme activity coincided with the specific mushroom growth stages.

COMBINATION OF SAWDUST, “FILTER CAKE” AND CALCIUM CARBONATE AS GROWTH MEDIUM FOR THE PRODUCTION OF WHITE OYSTER MUSHROOM (PLEUROTUS OSTREATUS)

This study was aimed to investigate the effect of combining sawdust (SD), filter cake (FC) and calcium carbonate as growth medium for the production of white oyster mushroom. Isolate F2 oyster mushroom was cultured on malt extract agar (MEA) and used in the experiment. The culture medium consisted of two treatments: first, A treatment: combined medium (A0=100% SD; A1=100% FC; A2=70% FC and 30% SD; A3=50% FC and 50% SD; A4=30% FC and 70% SD) and second, K treatment: addition of calcium carbonate (K1=2%; K2=3%; K3=4%; K4=5% weight of medium). A Randomized design was used to analyze certain parameters, such as mycelial growth, presence of fruiting body, the number of fruiting bodies and the fresh weight of fruiting body at harvest. The results showed that the highest mycelial growth and fruiting body formation occurred on A0 treatment. However, a high number of fruiting bodies and a high fresh weight of fruiting body at harvest were obtained on A4 treatment. Interaction between the combined medium (A) and addition of calcium carbonate (K) showed that the highest mycelial growth occurred on A0K2 treatment 30 days after incubation. The composition of A4 treatment (30% FC and 70% SD) was found to be the optimal medium for the production of fruiting body. This finding shows that FC with additional nutrition could as a substitute of SD medium for cultivating white oyster mushroom.

MRNA-seq and miRNA-seq profiling analyses reveal molecular mechanisms regulating induction of fruiting body in Ophiocordyceps sinensis

Ophiocordyceps sinensis has been a source of valuable materials in traditional Asian medicine for over two thousand years. With recent global warming and overharvest, however, the availability of these wild fungi has decreased dramatically. While fruiting body of O. sinensis has been artificially cultivated, the molecular mechanisms that govern the induction of fruiting body at the transcriptional and post-transcriptional levels are unclear. In this study, we carried out both mRNA and small RNA sequencing to identify crucial genes and miRNA-like RNAs (milRNAs) involved in the development of fruiting body. A total of 2875 differentially expressed genes (DEGs), and 71 differentially expressed milRNAs (DEMs) were identified among the mycoparasite complex, the sclerotium (ST) and the fruiting body stage. Functional enrichment and Gene Set Enrichment Analysis indicated that the ST had increased oxidative stress and energy metabolism and that mitogen-activated protein kinase signaling might induce the formation of fruiting body. Integrated analysis of DEGs and DEMs revealed that n_os_milR16, n_os_milR21, n_os_milR34, and n_os_milR90 could be candidate milRNAs that regulate the induction of fruiting body. This study provides transcriptome-wide insight into the molecular basis of fruiting body formation in O. Sinensis and identifies potential candidate genes for improving induction rate.

Functional analyses of Pleurotus ostreatus pcc1 and clp1 using CRISPR/Cas9

Understanding the molecular mechanisms controlling dikaryon formation in Agaricomycetes, which is basically controlled by A and B mating-type loci, contributes to improving mushroom cultivation and breeding. In Coprinopsis cinerea, various mutations in the SRY-type high mobility group protein-encoding gene, pcc1, were shown to activate the A-regulated pathway to induce pseudoclamp (clamp cells without clamp connection) and fruiting body formation in monokaryons. The formation of clamp cells was blocked in AmutBmut strain 326 with clp1-1 mutation in C. cinerea. However, considering the diverse mechanisms of sexual development among Agaricomycetes, it remains unclear whether similar phenotypes are also observed in clp1 or pcc1 mutants in cultivated mushrooms. Therefore, phenotypic analyses of Pleurotus ostreatus pcc1 or clp1 (Popcc1 or Poclp1) mutants generated using CRISPR/Cas9 were performed in this study. Plasmids with Cas9 expression cassette and different single guide RNAs targeting Popcc1 or Poclp1 were individually introduced into a monokaryotic P. ostreatus strain PC9 to obtain the mutants. Unlike in C. cinerea, the pseudoclamp cell was not observed in monokaryotic Popcc1 mutants, but it was observed after crossing two compatible strains with Popcc1 mutations. In Poclp1 mutants, dikaryosis was impaired as clamp cells were not observed after crossing, suggesting that Poclp1 functions may be essential for clamp cell formation, like in C. cinerea. These results provided a clue with respect to conserved and diverse mechanisms underlying sexual development in Agaricomycetes (at least between C. cinerea and P. ostreatus).

Development of cultivation method for Leucopaxillus giganteus fruiting bodies in Cryptomeria japonica artificial forests

ABSTRACT Sugi (Cryptomeria japonica) forests are devastated and abandoned in Japan. Although mushroom products are profitable, with the marketable ones expected to originate from Japanese forests, a few fungi mainly develop fruiting bodies in sugi forests in nature. With white mushrooms (Sugi-take) being popularly eaten by local residents in Mie prefecture, it is thus important that the mode of occurrence of white mushrooms found in the forests is investigated to determine the possibility of marketable forest products in sugi forests. In the phylogenetic tree constructed based on the internal transcribed region of rDNA, white mushrooms were divided into two groups; Leucopaxillus giganteus (a synonym of Aspropaxillus giganteus) and Aspropaxillus, and Clitocybe sp. and L. tricolor. The cultivation method of L. giganteus, which is the most functional mushroom among the three species, was examined. L. giganteus fruiting bodies formed a fairy ring at a distance of 1 m from the point of burial of 40 kg media in the sugi forest. L. giganteus fruiting body formation was observed until 5 years post-inoculation. The yield was 3.8–13.4 kg/year and the total yield for 5 years was 43.2 kg. The fruiting body yield buried in spring was higher than that buried in autumn. The highest yield was obtained when 40 kg of media was buried in the forest soil. This study established a method for cultivating L. giganteus in the sugi forest of Japan.

STRIPAK, a Key Regulator of Fungal Development, Operates as a Multifunctional Signaling Hub.

The striatin-interacting phosphatases and kinases (STRIPAK) multi subunit complex is a highly conserved signaling complex that controls diverse developmental processes in higher and lower eukaryotes. In this perspective article, we summarize how STRIPAK controls diverse developmental processes in euascomycetes, such as fruiting body formation, cell fusion, sexual and vegetative development, pathogenicity, symbiosis, as well as secondary metabolism. Recent structural investigations revealed information about the assembly and stoichiometry of the complex enabling it to act as a signaling hub. Multiple organellar targeting of STRIPAK subunits suggests how this complex connects several signaling transduction pathways involved in diverse cellular developmental processes. Furthermore, recent phosphoproteomic analysis shows that STRIPAK controls the dephosphorylation of subunits from several signaling complexes. We also refer to recent findings in yeast, where the STRIPAK homologue connects conserved signaling pathways, and based on this we suggest how so far non-characterized proteins may functions as receptors connecting mitophagy with the STRIPAK signaling complex. Such lines of investigation should contribute to the overall mechanistic understanding of how STRIPAK controls development in euascomycetes and beyond.

Unveiling the Functions of the VosA-VelB Target Gene vidD in Aspergillus nidulans

The velvet regulators VosA and VelB are primarily involved in spore maturation and dormancy. Previous studies found that the VosA-VelB hetero-complex coordinates certain target genes that are related to fungal differentiation and conidial maturation in Aspergillus nidulans. Here, we characterized the VosA/VelB-inhibited developmental gene vidD in A. nidulans. Phenotypic analyses demonstrated that the vidD deleted mutant exhibited defect fungal growth, a reduced number of conidia, and delayed formation of sexual fruiting bodies. The deletion of vidD decreased the amount of conidial trehalose, increased the sensitivity against heat stress, and reduced the conidial viability. Moreover, the absence of vidD resulted in increased production of sterigmatocystin. Together, these results show that VidD is required for proper fungal growth, development, and sterigmatocystin production in A. nidulans.

Transcriptome of different fruiting stages in the cultivated mushroom Cyclocybe aegerita suggests a complex regulation of fruiting and reveals enzymes putatively involved in fungal oxylipin biosynthesis

BackgroundCyclocybe aegerita (syn. Agrocybe aegerita) is a commercially cultivated mushroom. Its archetypal agaric morphology and its ability to undergo its whole life cycle under laboratory conditions makes this fungus a well-suited model for studying fruiting body (basidiome, basidiocarp) development. To elucidate the so far barely understood biosynthesis of fungal volatiles, alterations in the transcriptome during different developmental stages of C. aegerita were analyzed and combined with changes in the volatile profile during its different fruiting stages.ResultsA transcriptomic study at seven points in time during fruiting body development of C. aegerita with seven mycelial and five fruiting body stages was conducted. Differential gene expression was observed for genes involved in fungal fruiting body formation showing interesting transcriptional patterns and correlations of these fruiting-related genes with the developmental stages. Combining transcriptome and volatilome data, enzymes putatively involved in the biosynthesis of C8 oxylipins in C. aegerita including lipoxygenases (LOXs), dioxygenases (DOXs), hydroperoxide lyases (HPLs), alcohol dehydrogenases (ADHs) and ene-reductases could be identified. Furthermore, we were able to localize the mycelium as the main source for sesquiterpenes predominant during sporulation in the headspace of C. aegerita cultures. In contrast, changes in the C8 profile detected in late stages of development are probably due to the activity of enzymes located in the fruiting bodies.ConclusionsIn this study, the combination of volatilome and transcriptome data of C. aegerita revealed interesting candidates both for functional genetics-based analysis of fruiting-related genes and for prospective enzyme characterization studies to further elucidate the so far barely understood biosynthesis of fungal C8 oxylipins.

Three PilZ Domain Proteins, PlpA, PixA, and PixB, Have Distinct Functions in Regulation of Motility and Development in Myxococcus xanthus.

ABSTRACTIn bacteria, the nucleotide-based second messenger bis-(3′-5′)-cyclic dimeric GMP (c-di-GMP) binds to effectors to generate outputs in response to changes in the environment. In Myxococcus xanthus, c-di-GMP regulates type IV pilus-dependent motility and the starvation-induced developmental program that results in formation of spore-filled fruiting bodies; however, little is known about the effectors that bind c-di-GMP. Here, we systematically inactivated all 24 genes encoding PilZ domain-containing proteins, which are among the most common c-di-GMP effectors. We confirm that the stand-alone PilZ domain protein PlpA is important for regulation of motility independently of the Frz chemosensory system and that Pkn1, which is composed of a Ser/Thr kinase domain and a PilZ domain, is specifically important for development. Moreover, we identify two PilZ domain proteins that have distinct functions in regulating motility and development. PixB, which is composed of two PilZ domains and an acetyltransferase domain, binds c-di-GMP in vitro and regulates type IV pilus-dependent and gliding motility in a Frz-dependent manner as well as development. The acetyltransferase domain is required and sufficient for function during growth, while all three domains and c-di-GMP binding are essential for PixB function during development. PixA is a response regulator composed of a PilZ domain and a receiver domain, binds c-di-GMP in vitro, and regulates motility independently of the Frz system, likely by setting up the polarity of the two motility systems. Our results support a model whereby PlpA, PixA, and PixB act in independent pathways and have distinct functions in regulation of motility.IMPORTANCE c-di-GMP signaling controls bacterial motility in many bacterial species by binding to downstream effector proteins. Here, we identify two PilZ domain-containing proteins in Myxococcus xanthus that bind c-di-GMP. We show that PixB, which contains two PilZ domains and an acetyltransferase domain, acts in a manner that depends on the Frz chemosensory system to regulate motility via the acetyltransferase domain, while the intact protein and c-di-GMP binding are essential for PixB to support development. In contrast, PixA acts in a Frz-independent manner to regulate motility. Taking our results together with previous observations, we conclude that PilZ domain proteins and c-di-GMP act in multiple independent pathways to regulate motility and development in M. xanthus.

Selection and Evaluation of Potential Reference Genes for Quantitative Real-Time PCR in Agaricus blazei Based on Transcriptome Sequencing Data

Quantitative real-time PCR (qRT-PCR) is widely used to detect gene expression due to its high sensitivity, high throughput, and convenience. The accurate choice of reference genes is required for normalization of gene expression in qRT-PCR analysis. In order to identify the optimal candidates for gene expression analysis using qRT-PCR in Agaricus blazei, we studied the potential reference genes in this economically important edible fungus. In this study, transcriptome datasets were used as source for identification of candidate reference genes. And 27 potential reference genes including 21 newly stable genes, three classical housekeeping genes, and homologous genes of three ideal reference genes in Volvariella volvacea, were screened based on transcriptome datasets of A. blazei and previous studies. The expression stability of these genes was investigated by qRT-PCR analysis and further evaluated by four software packages, geNorm, NormFinder, BestKeeper, and RefFinder. Among these candidates, α-TUB (Tubulin alpha) and Cox5a (COX5A subunit VA of cytochrome c oxidase) were revealed as the most stable in fruit body, and suitable for 5 different developmental stages. α-TUB and ATP3 (ATP3 gamma subunit of the F1 sector of mitochondrial F1F0 ATP synthase) showed the most stable expression in stipe tissues and, Uqcrc (core subunit of the ubiquinol-cytochrome c reductase complex) and PUP3 (20S proteasome subunit beta 3) performed well in pileus tissues during the process of A. blazei development, while GAPDH (glyceraldehyde-3-phosphate dehydrogenase) was among the least stable genes in all sample sets. Finally, the Ableln3 (homology of eln3 gene of Coprinus cinereus) was adopted to validate the reliability of these stable and unstable reference genes, indicating that the use of unsuitable reference genes as internal controls could change the target gene’s expression pattern. This study can provide guidance for choosing reference genes for analyzing the expression pattern of target genes and facilitate the functional genomic investigation on fruit body formation and development, as well as stipe elongation and pileus expansion in A. blazei.

Premix Fungicides That Reduce Development of Fruiting Bodies But Not Leaf Lesions by Stagonosporopsis citrulli on Watermelon Leaves in the Field.

Fungicide applications are the main method to manage gummy stem blight on watermelon (Citrullus lanatus) and other cucurbits, but it is unknown whether fungicides affect development of leaf lesions or fruiting bodies by Stagonosporopsis citrulli. Cyprodinil plus fludioxonil (Switch), cyprodinil plus difenoconazole (Inspire Super), cyprodinil (Vangard), fludioxonil (Cannonball), and difenoconazole (Inspire) were applied to watermelon in rotation with chlorothalonil (Bravo) in fall 2017, 2018, and 2019. Water and chlorothalonil applied weekly served as control treatments. All fungicides reduced disease severity (percentage of leaf area diseased) and area under the disease progress curve (AUDPC) in field plots compared with water. Cyprodinil plus fludioxonil and cyprodinil plus difenoconazole reduced disease severity and AUDPC more than chlorothalonil. Fungicides did not affect the number, diameter, expansion, or area of lesions. All fungicides reduced the number of lesions with fruiting bodies of S. citrulli compared with water (P < 0.05). Cyprodinil plus fludioxonil and cyprodinil plus difenoconazole reduced the percentage of leaf lesions with fruiting bodies, and the diameter and area of the portions of leaf lesions covered with fruiting bodies, compared with water and chlorothalonil. Premix fungicides containing cyprodinil reduced fruiting body formation by S. citrulli, which may partially explain their efficacy in managing gummy stem blight.

The transcription factor FvHmg1 negatively regulates fruiting body development in Winter Mushroom Flammulina velutipes.

Fruiting body formation in Agaricomycetes represents the most complex and unclear process in the fungi. Mating type pathways (matA and matB) and transcription factors are important regulators in the process. Here, we report a new High-mobility-group (HMG) box domain protein FvHmg1 that acts as a negative transcription regulator in fruiting body development in Winter Mushroom Flammulina velutipes. However, the expression of Fvhmg1 in dikaryon and primordial stages was significantly lower than that of monokaryon. The Fvhmg1-RNAi mutants had a better ability of fruiting than wild type strain. Overall expression of Fvhmg1 was controlled under compatible matA and matB genes where compatible matA genes could increase its expression level, while compatible matB genes had the opposite effect. It means when two monokaryons with compatible matA and matB genes were crossed, the negatively transcription factor FvHmg1 was inhibited, and normal fully fruiting body could formation and develop. The relationship between FvHmg1 and mating type pathway would advance to understand of sexual reproduction and fruiting body development in edible mushrooms.

Kültür mantarı ve yeşil küf hastalığının kompost ve örtü toprağındaki biyotik interaksiyonları

Presence of Trichoderma aggressivum f. aggressivum (green mold disease) either in compost or casing soil causes significant yield losses in button mushroom (Agaricus bisporus) cultivation. The aim of this study was to examine biotic interactions between A. bisporus and T. aggressivum f. aggressivum in compost and casing soil. In the study, strains (brown and white) of A. bisporus and isolates (Şem1/1 and K3) of T. aggressivum f. aggressivum were used. Experiments (compost and casing soil) were conducted according to completely randomized design in factorial with four replications. Yield values of each experiment were established by weighing sporophores (mushrooms) in each plot. Mean yield values of each treatment were compared with others. Presence of the T. aggressivum f. aggressivum isolates in compost and casing soil significantly (P˂0.01) inhibited mycelial growth and fruiting body formation of both strains of A. bisporus. In the presence of the T. aggressivum f. aggressivum isolates in casing soil, average yield loss of the strains of A. bisporus was 36.41%, while it was 29.35% in the presence of the T. aggressivum f. aggressivum isolates in compost. Average yield loss of the white strain of A. bisporus was 49.68%, whereas it was 16.08% in the brown strain. The study revealed that presence of T. aggressivum f. aggressivum in casing soil could be much more negative influence on yield of A. bisporus than that of compost and brown strain of A. bisporus could be more resistant to T. aggressivum f. aggressivum than white strain.

Inhibiting Neddylation with MLN4924 Suppresses Growth and Delays Multicellular Development in Dictyostelium discoideum.

Neddylation is a post-translational modification that is essential for a variety of cellular processes and is linked to many human diseases including cancer, neurodegeneration, and autoimmune disorders. Neddylation involves the conjugation of the ubiquitin-like modifier neural precursor cell expressed developmentally downregulated protein 8 (NEDD8) to target proteins, and has been studied extensively in various eukaryotes including fungi, plants, and metazoans. Here, we examine the biological processes influenced by neddylation in the social amoeba, Dictyostelium discoideum, using a well-established inhibitor of neddylation, MLN4924 (pevonedistat). NEDD8, and the target of MLN4924 inhibition, NEDD8-activating enzyme E1 (NAE1), are highly conserved in D. discoideum (Nedd8 and Nae1, respectively). Treatment of D. discoideum cells with MLN4924 increased the amount of free Nedd8, suggesting that MLN4924 inhibited neddylation. During growth, MLN4924 suppressed cell proliferation and folic acid-mediated chemotaxis. During multicellular development, MLN4924 inhibited cyclic adenosine monophosphate (cAMP)-mediated chemotaxis, delayed aggregation, and suppressed fruiting body formation. Together, these findings indicate that neddylation plays an important role in regulating cellular and developmental events during the D. discoideum life cycle and that this organism can be used as a model system to better understand the essential roles of neddylation in eukaryotes, and consequently, its involvement in human disease.

Artificial Cultivation Characteristics and Bioactive Effects of Novel Tropicoporus linteus (Syn. Phellinus linteus) Strains HN00K9 and HN6036 in Korea

Phellinus strains were collected from different areas in Korea. Of them, the fast mycelial growing strains were artificially cultivated on the oak logs to produce fruiting body. The varieties, Phellinus linteus ASI26099 (Korea Sanghwang) and P. baumii PBJS (Jangsoo Sanghwang) were grown under the same conditions as controls. Their cultivating characteristics including mycelial colonization, pinhead formation, and fruiting body formation rate were investigated on the logs. Basidiocarps of Phellinus strains HN00K9, HN6036, and ASI26099 were concentrically zonate and shallowly sulcate, and dark chestnut showing typical characteristics of Tropicoporus linteus (synonyum: P. linteus, Inonotus linteus, polyporus linteus), which is distinguishably different to PBJS. HN00K9 showed the highest yield of fruiting body among the mushroom strains. The β-glucan content in fruiting bodies of HN00K9 was 20% higher than those of other strains. Bioactive effects of polysaccharide samples from fruiting bodies of Phellinus strains, HN00K9, HN6036, ASI26099, and PBJS were assessed on cell viability and cytokine (IL-6 and TNF-α) inhibition and finally on anticancer to different human cancer cells.

Waste-free fungi production in the Russian Federation

Due to their pleasant taste, high protein levels, and tonic and medicinal value, fungi are clearly one of the world’s largest untapped resources of nutritious and delicious food for humanity. Different types of fungi have different abilities to use substrates. This depends on the specific enzymes secreted by the individual fungus. Commercially cultivated fungi show different abilities to use different lignocellulolytic substances as a substrate for growth and formation of fruit bodies. Fungi growing fits perfectly into the production line with such branches of agriculture as crop production and animal husbandry, as in its technological process it uses raw materials that are waste from these branches of agricultural production, disposes of them and gets a cost-effective output of food-valuable and environmentally friendly products.

NGHIÊN CỨU ẢNH HƯỞNG CỦA CƠ CHẤT ĐẾN MỘT SỐ CHỈ TIÊU SINH TRƯỞNG, NĂNG SUẤT CỦA NẤM LINH CHI ĐỎ (Ganoderma lucidum)

The research aimed to evaluate the effects of 3 types of substrate (containing the main ingredient being Bodhi sawdust, which was treated and mixed according to 3 different formulas) on the growth and productivity of red reishi mushrooms. The results of the study showed that, of the three types of research medium formulations, Bodhi sawdust treated long-term with incubating for 168 hours was the substrate for the highest mushroom yield, reaching 96.73 g\bag, showing through the indexes of the number of fruiting body bunches\bag (3.47 bunches), fruiting body thickness (1.09 cm), fruiting body diameter (14.8 cm), polysaccharide content of mushroom (2.128%). Meanwhile, the substrate containing 70% sawdust and 30% straw substrates had the highest mycelial growth rate (1.02 cm\day) and the shortest mycelial growth time (the mushroom silk covered the whole bag at 26.3 days). Compared with the above two types of media, the formula using sawdust for short-term treatment (incubated for 48 hours) is ineffective in both the mycelial growth and fruiting body formation stages. The obtained research results contribute to perfecting the production process of red reishi mushrooms on the substrate of agricultural by-products, reducing environmental pollution and bringing economic efficiency to the farmers.

Mathematical Modelling of Contact-Dependent Motility Coordination in Myxococcus Xanthus

Myxococcs xanthus exhibits “social” behaviors, such as cooperative feeding and fruiting-body formation, through intercellular communication and coordination. A particular intriguing intercellular coordination lies in coordination of motility between cells with physical contacts. Specifically, M. xanthus cells glide on substrate with periodic reversals, and physical contacts with opposite-moving colony mates regulate their reversal frequency. This contact-dependent motility coordination is known to be necessary for generating intriguing population patterns, such as rippling waves.