Auricularia heimuer is a wood-rotting edible mushroom, and with the continuous development of the industry, the research on its grass-rotting cultivation is becoming more and more important. In this study, A. heimuer was cultivated using herbaceous substrate (reed) completely replacing the traditional woody substrate (oak), and the correlation between the relative expression of cellulase gene, cellulase activity, cellulose degradation and yield of different strains of A. heimuer were studied by combining qRT-PCR technology at different growth stages. The results showed that the cellulose degradation were positively correlated with the yield of reed and sawdust substrate at two growth stages, and were positively correlated with three cellulase activities. The relative expression of four cellulase genes were positively correlated with enzyme activity. There were inter-strain differences in the expression of the enzyme genes, which were basically consistent with the trend of the enzyme activity of the strains; g5372 and g7270 were more actively expressed in the mycelium period, while g9664 and g10234 were more actively expressed in the fruiting period. The results of SEM showed that the mycelium of A15 and A125 were different in their ability to degrade and utilize lignocellulose in reed substrate. The parental hybridization test further verified that qRT-PCR could be used as a rapid method to evaluate the cellulose degradation ability of A. heimuer strains. Seven strains (A12, A15, A184, A224, Z6, Z12, and Z18) with high cellulose degradation ability were screened. This study provides a reference for further understanding the role of A. heimuer cellulase genes in the degradation and metabolism of cellulose and for breeding new varieties more suitable for herbaceous substrate cultivation.

Zinc and lysine have been identified as beneficial components of Flammulina filiformis. This work investigated the effects of different concentrations of Zn²⁺ on mycelia growth, zinc content, amino acid composition of F. filiformis. To explore the mechanism of action of zinc on lysine synthesis in F. filiformis mycelia, this work studied at the molecular level. The cultivated strain FV8 and the wild strain FV18 were utilized as the research subjects. Various concentrations of Zn²⁺ (0, 10, 20, 30 mg/L) were added in the PDA medium for the experiments. The results indicated that the maximum lysine content was reached in the 20 mg/L treatment. A positive correlation was identified between Zn²⁺ and the lysine content in F. filiformis mycelia, suggesting a regulatory role for Zn²⁺ in the expression of lysine synthesis pathway genes. Zn²⁺ has been observed to promote the upregulated expression of HDH and HCD, while concomitantly exerting a negative effect on the expression of AAT in key enzyme genes of the lysine synthesis pathway. The F. filiformis mycelia exhibited a notable enrichment capacity for zinc, with the highest zinc content observed in the 30 mg/L treatment. The zinc-enriched growth performance of wild strain FV18 was found to be superior to that of cultivated strain FV8, which is considered a suitable breeding material. This study provides a foundation for further exploration of the lysine synthesis pathway in F. filiformis mycelia, and selection of functional varieties of F. filiformis.

Auricularia cornea is rich in nutrients and bioactive compounds, and with the continuous expansion of its industrial cultivation, elucidating the genetic basis of key agronomic traits is essential for marker-assisted breeding and cultivar improvement. In this study, 140 A. cornea germplasm accessions representing diverse geographic origins were subjected to a comprehensive two-year phenotypic evaluation of ten agronomic traits, including FBL, FBW, FBT, Yield, MGR, GP, and fruiting body color. The results showed that all traits exhibited substantial genetic variation across the population, and most traits displayed high heritability. Genome-wide association studies (GWAS) identified 1178 and 821 SNPs significantly associated with agronomic traits in the two respective years, with yield-related loci predominantly located on chromosome 9. Based on an integrated significance threshold, ten core SNPs were ultimately retained, and 42 putative candidate genes were identified within ±5kb flanking regions of these SNPs. These candidate genes were mainly involved in cell wall polysaccharide modification, redox regulation, pigment biosynthesis, metabolic processes, and signal transduction. Furthermore, haplotype analysis identified six superior haplotypes associated with ear morphology, yield, MGR, and GP, and accessions carrying these superior haplotypes exhibited significantly enhanced phenotypic performance. Overall, this study provides a systematic dissection of the genetic architecture of important agronomic traits in A. cornea and offers a solid theoretical foundation for high-yield and high-quality molecular breeding and genetic improvement.

To address the “fungus-forest conflict” in the edible mushroom industry and the challenge of resource utilization for bamboo substrate waste, this study focused on white Auricularia cornea, and cultivation systems were established with bamboo substrate replacing wood chips at ratios of 0%, 18%, 38%, 58%, and 78%. By integrating liquid chromatography–tandem mass spectrometry (LC-MS/MS) analysis with agronomic trait measurements, the study elucidated the metabolic adaptation mechanisms of the substrate. Results indicated that white A. cornea could grow normally in all bamboo substrates, with the 58% bamboo substrate replacement group (D_58) demonstrating the most optimal overall performance. The mycelial growth rate reached 3.55 ± 0.24 mm/d, and the growth period was the shortest (86.2 d), balancing growth efficiency with cost advantages. Metabolomics detected 3779 metabolites, primarily amino acids and their derivatives (42.2%) and organic acids (35.54%). Compared to the control group, each treatment group exhibited 104–528 upregulated and 192–630 downregulated differential metabolites, with 93 shared differential metabolites and numerous unique markers. KEGG pathway enrichment analysis revealed that varying bamboo substrate ratios shaped growth adaptation strategies by regulating core pathways such as nucleotide metabolism and ABC transporters. This study established the feasibility and optimal formulation of bamboo substrate substitution, elucidated the substrate–metabolite–phenotype linkage mechanism, and provided theoretical foundations and practical references for high-quality cultivation of white A. cornea and sustainable development through “substituting bamboo for wood” to reduce carbon emissions.