Grifola frondosa is a valuable edible fungus with high nutritional and medicinal values. The mating systems of fungi not only offer practical strategies for breeding, but also have far-reaching effects on genetic variability. Grifola frondosa has been considered as a sexual species with a tetrapolar mating system based on little experimental data. In the present study, one group of test crosses and six groups of three-round mating experiments from two parental strains were conducted to determine the mating system in G. frondosa. A chi-squared test of the results of the test-cross mating experiments indicated that they satisfied Mendelian segregation, while a series of three-round mating experiments showed that Mendelian segregation was not satisfied, implying a segregation distortion phenomenon in G. frondosa. A genomic map of the G. frondosa strain, y59, grown from an LMCZ basidiospore, with 40.54 Mb and 12 chromosomes, was generated using genome, transcriptome and Hi-C sequencing technology. Based on the genomic annotation of G. frondosa, the mating-type loci A and B were located on chromosomes 1 and 11, respectively. The mating-type locus A coded for the β-fg protein, HD1, HD2 and MIP, in that order. The mating-type locus B consisted of six pheromone receptors (PRs) and five pheromone precursors (PPs) in a crossed order. Moreover, both HD and PR loci may have only one sublocus that determines the mating type in G. frondosa. The nonsynonymous SNP and indel mutations between the A₁B₁ and A₂B₂ mating-type strains and the reference genome of y59 only occurred on genes HD2 and PR1/2, preliminarily confirming that the mating type of the y59 strain was A₁B₂ and not A₁B₁. Based on the genetic evidence and the more reliable molecular evidence, the results reveal that the mating system of G. frondosa is tetrapolar. This study has important implications for the genetics and hybrid breeding of G. frondosa.

Cordyceps militaris is one of the commercially cultivated mushrooms, valued for its medicinal and nutritional benefits. However, the fruiting body development mechanism has remained elusive. Chitin synthases (CHSs) are ubiquitous enzymes involved in the regulation of fungal growth, development and virulence. In this study, a total of eight CmChs genes were identified. Chromosomal localization analysis revealed an uneven distribution of CmCHSs across the C. militaris genome. Based on the phylogenetic analysis, 100 CHSs from Cordyceps sensu lato, encompassing C. militaris, were categorized into three divisions and seven classes, shedding light on their evolutionary relationships. There was no significant difference in the number of CHSs between ascomycetes and basidiomycetes in general (p = 0.067), as well as between pathogenic and saprotrophic fungi in general (p = 0.151 and 0.971 in Ascomycota and Basidiomycota fungi, respectively). This underscored the essential and conserved nature of these CHSs across various fungal lifestyles and ecological niches. The different transcript patterns of the eight CmChss during key life cycle stages, such as conidia germination, infection, and fruiting body development, indicated that each CHS gene may have a distinct role during specific stages of the life cycle. In conclusion, these findings indeed lay the groundwork for a further exploration of the functional roles of CHSs in the regulatory mechanism of fruiting body development in C. militaris.

Morchella spp. are rare and highly valued edible fungi that often exhibit unstable yield and quality under protected cultivation due to inadequate regulation of the light and temperature microenvironment. Colored films can effectively optimize these conditions. In this study, the effects of six colored film treatments—white film (WM), red film (RM), green film (GM), blue film (BM), black film (BKM), and silver-black film (SBM)—on the microenvironment and development of Morchella septimelata and M. sextelata were investigated. The results showed that the BM treatment improved the microenvironment and promoted Morchella development. BM exhibited high transmittance, enhancing light intensity and increasing accumulated air and soil temperatures. It also led to the production of the greatest number of mature fruiting bodies, with 46 per square meter for M. septimelata and 54 per square meter for M. sextelata. Agronomic traits were also superior under the BM treatment, with pileus lengths of 82.97 mm for M. septimelata and 70.76 mm for M. sextelata. Compared with WM, BM significantly increased the weight of a single fruiting body and yield by 12.23% and 20.86% for M. septimelata and by 18.14% and 25.34% for M. sextelata, respectively. BM also significantly increased crude fiber content by 16.92% in M. septimelata and 2.63% in M. sextelata. RM significantly increased crude polysaccharide content by 47.42% in M. septimelata and by 44.12% in M. sextelata. This study indicated that BM was the preferred choice for Morchella protected cultivation.

A genetic linkage map of Grifola albicans f. huishuhua (Maitake) is an important resource for chromosome analysis and the genetic basis of phenotypic variation determination. A total of 92 monokaryotic isolates were selected from the F1 generation of Q3-8 × Y1-18 in this study. Restriction site-associated DNA sequencing, as well as identification of single nucleotide polymorphisms (SNPs), was performed, aiming to illustrate a high-density genetic linkage map. A total of 1122 high-quality SNP markers were located on a map with a length of 1473.60 centimorgan (cM) by screening 589534 SNPs. This map covers 12 linkage groups (LGs) with an average genetic distance of 122.80 cM. Three quantitative trait loci (QTLs) related to the growth rate of G. albicans f. huishuhua strains were identified using the composite interval mapping method. These QTLs were mapped to linkage groups (LGs) as follows: LG3 (qmgv), LG4 (qmb), LG5 (qmd), LG8 (qrdm1, qrdm2), and LG10 (qmgrc1, qmgrc2, qmgrc3). The genes associated with mycelial growth rate and biomass production of these strains were identified. This information could be used for molecular marker-assisted selective breeding in G. albicans f. huishuhua.

Paramarasmius mesosporus is a wild edible mushroom with a strong aroma and high culinary value, capable of growing at temperatures up to 36 °C. However, its domestication system and the genetic basis of its sexual reproduction remain largely unexplored. In this study, fresh fruiting bodies of P. mesosporus were collected from the rhizosphere of Imperata spp. in saline–alkali land in Hebei Province, China. The species was successfully domesticated for the first time, and fruiting bodies were harvested 7–10 days after spawning. A chromosome-level genome of the monokaryotic strain ‘Q2’ was assembled using whole-genome sequencing, transcriptome analysis, and Hi-C technology, with a total size of 46.57 Mb that was anchored onto 11 pseudochromosomes at a mounting rate of 95.18%. The mating-type system was identified as a typical tetrapolar heterothallic type, with the MAT A and MAT B loci located on chromosomes 2 and 10, respectively. The MAT A locus encodes HD1, HD2, MIP, and β-fg, among which tr-HD1 was found to be pseudogenized due to domain truncation. The MAT B locus comprises seven pheromone receptor genes and seven pheromone precursor genes arranged in an interspersed pattern. Based on these genomic features, a preliminary MAPK signaling pathway model was proposed to elucidate the molecular regulation of sexual reproduction. This study achieved the first artificial domestication and cultivation of P. mesosporus. systematically elucidated genomic characteristics and mating-type molecular mechanisms of this species were systematically elucidated, providing a theoretical foundation for hybrid breeding, molecular marker-assisted selection, and genetic improvement. These findings hold significant scientific and applied value for germplasm innovation and industrial development of this rare edible mushroom.

Stropharia rugosoannulata is a widely cultivated edible fungus with high economic and nutritional value. It is a tetrapolar heterothallic basidiomycete. The development of single nucleotide polymorphism (SNP) markers for mating-type identification holds considerable promise for enhancing breeding efficiency. In our study, one group of test crosses and three-round mating experiments from one parental strain were conducted in order to ascertain the mating type in this species. Segregation distortion in mating types was observed after single-spore isolation, which was deviated from Mendelian inheritance. The monokaryotic strain Q25 was derived from the dikaryotic mycelium S1 of S. rugosoannulata. The genome map of strain Q25 with 48.27 Mb and 14 chromosomes was constructed using genomic, transcriptomic, and high-throughput chromosome conformation capture (Hi-C) sequencing technologies. The locations of mating-type loci were identified using genomic annotation. The mating-type A locus is located in chromosome 1, with the gene sequence of β-fg, HD2, HD1, and MIP. The mating-type B locus is located in chromosome 12. It contains five pheromone receptors and five pheromone precursor genes. Two pairs of highly specific and stable primers were designed based on SNP loci in A and B mating types. A1, A2, B1, and B2 alleles were precisely distinguished with these primers, which were subsequently applied in cultivation experiments. This study lays a foundation for the precise breeding of S. rugosoannulata.