Auricularia heimuer is one of the most popular edible fungi in China. In this study, the whole genome of A. heimuer was sequenced on the Illumina HiSeq X system and compared with other mushrooms genomes. As a wood-rotting fungus, a total of 509 carbohydrate-active enzymes (CAZymes) were annotated in order to explore its potential capabilities on wood degradation. The glycoside hydrolases (GH) family genes in the A. heimuer genome were more abundant than the genes in the other 11 mushrooms genomes. The A. heimuer genome contained 102 genes encoding class III, IV, and V ethanol dehydrogenases. Evolutionary analysis based on 562 orthologous single-copy genes from 15 mushrooms showed that Auricularia formed an early independent branch of Agaricomycetes. The mating-type locus of A. heimuer was located on linkage group 8 by genetic linkage analysis. By combining the genome sequence analysis with the genetic linkage map, the mating-type locus of A. heimuer was located on scaffold45 and consisted of two subunits, α and β. Each subunit consisted of a pair of homeodomain mating-type protein genes HD1 and HD2. The mapping revealed conserved synteny at the whole mating-type loci and mirror symmetry relations near the β subunit between A. heimuer and Exidia glandulosa. This study proposed the potential for the bioethanol production by consolidated bioprocessing of A. heimuer. It will promote understanding of the lignocellulose degradation system and facilitate more efficient conversion of the agricultural wastes used for mushroom cultivation. It also will advance the research on the fruiting body development and evolution of A. heimuer.

Morchella is an edible mushroom with medical applciations. To explore the correlation between the texture indices of Morchella and to establish a sensory quality evaluation system, the texture quality characteristics of 214 Morchella germplasm resources from our country were analyzed via the Texture Profile Analysis (TPA) method on a texture analyzer. The research revealed significant differences in the texture quality characteristics of both the pileus and stipe among Morchella populations. After the Kolmogorov–Smirnov test, the six texture characteristics were seen to conform to a normal distribution. According to the correlation analysis, there was a significant correlation between the texture characteristics of the pileus, and a significant positive correlation between the hardness and the gumminess of the stipe (correlation coefficient of 0.96). Additionally, the hardness was negatively correlated with cohesiveness and resilience, with correlation coefficients of −0.51 and −0.38. Variation analysis indicated abundant genetic variation in each characteristic. Furthermore, the coefficient of variation for the characteristics of Morchella sextalata was higher than those of other species. Principal component analysis simplified the texture evaluation indices of Morchella pileus into a palatable factor and cohesive factor, and arranged the texture evaluation indexes of Morchella stipe into toughness–hardness factor and cohesive factor. Through comprehensive evaluation and cluster analysis, 10 Morchella strains were selected for subsequent use as breeding or cultivation materials. By comparing three different methods, the ‘probability grading method’ was determined to be the most suitable evaluation method for the texture quality characteristics of Morchella. The research results established a texture evaluation system for Morchella, offering a reference for selecting and cultivating breeds with superior texture qualities.

To rationally utilize Morchella germplasm resources, this study investigated 13 phenotypic traits in 231 Chinese Morchella germplasm accessions. Accessions were grouped by cap color traits and analyzed using four sampling methods (simple proportion method, logarithmic proportion method, square root proportion method, and diversity proportion method) five sampling sizes (10%, 15%, 20%, 25%, and 30%), two genetic distances (Euclidean distance and Mahalanobis distance), and four clustering methods (class-means, minimum distance, maximum distance, and sum of squared deviations) to explore optimal sampling strategies and select core collection. Core collection for the optimal sampling strategy was selected based on six indicators: percentage difference in mean, percentage difference in variance, range conformity rate, coefficient of variation change rate, phenotypic frequency variance, and phenotypic retention ratio. Phenotypic traits of the core germplasm were evaluated using genetic diversity eigenvalues, t-tests, F-tests, and systematic clustering, with confirmation via principal component analysis. Results indicated that the logarithmic ratio method yielded optimal sampling, with 15% representing the optimal sample size. Euclidean distance outperformed Mahalanobis distance, and the maximum distance method proved optimal for clustering. Ultimately, 34 Morchella germplasm resources were selected, accounting for 14.72% of the total germplasm (original germplasm). Under the P < 0.05 probability threshold, the mean, standard deviation, coefficient of variation, and genetic diversity indices of the core collection showed no significant differences from the original germplasm. Cluster analysis revealed consistent grouping of germplasm resources and phenotypic trait clusters between the core and original germplasm. In principal component analysis, the eigenvalues and cumulative contribution rates of the first four principal components were higher for the core collection than for the original germplasm. This indicates that the core collection eliminated most genetic redundancy while retaining the genetic diversity of the original germplasm, demonstrating its representative selection. This study provides a reference basis for the effective utilization and germplasm innovation of Morchella germplasm resources.

To rationally utilize Morchella germplasm resources, this study investigated 13 phenotypic traits in 231 Chinese Morchella germplasm accessions. Accessions were stratified by cap color and subjected to comparative analyses using four sampling methods, five sampling intensities, two genetic distance metrics, and four hierarchical clustering algorithms to determine the optimal strategy for core collection construction. The optimal sampling strategy for core collection construction was identified using six evaluation. Phenotypic traits of the core collection were evaluated using genetic diversity eigenvalues, t-tests, F-tests, and systematic clustering, with confirmation via principal component analysis. The results indicate that the logarithmic ratio method yielded the smallest differences in group proportions, making it the optimal sampling method. A 15% sample intensity proved optimal, with Euclidean distance outperforming Mahalanobis distance. The longest-distance method was determined to be the optimal clustering approach. Within the optimal sampling strategy combination, the CR value reached its maximum (97.77%). Ultimately, 34 Morchella germplasm resources were extracted, accounting for 14.72% of the total germplasm (original germplasm). The mean values, standard deviations, and genetic diversity of phenotypic traits were similar between the original germplasm and the core collection. However, the coefficient of variation for quantitative traits showed significant differences. In the t-test, only the maturity period showed a significant difference. In the F-test, only the cap length/width and maturity period showed significant differences. Cluster analysis grouped the germplasm resources of the core collection and the original germplasm into relatively consistent clusters. In principal component analysis, the eigenvalues and cumulative contribution rates of the first four principal components were higher for the core collection than for the original germplasm. This indicates that the core collection eliminated most genetic redundancy while preserving the genetic diversity of the original germplasm. The core collection selection is representative and can be effectively utilized as breeding material. This study provides a reference for the effective utilization and germplasm innovation of Morchella germplasm resources.