True morels (Morchella, Pezizales) cultivated in soil are subject to complex influences from soil microbial communities. To explore the characteristics of soil microbial communities on morel cultivation, and evaluate whether these microbes are related to morel production, we collected 23 soil samples from four counties in Sichuan and Yunnan Provinces, China. Based on ITS and 16S rDNA amplicon sequencing, the alpha diversity analysis indicated that the biodiversity of morel cultivation soil showed a downward trend compared with the bare soil. The results also showed that there were no significant differences in soil microbial communities between OC (bare soil) and OO (after one-year suspension of sowing). This means that, after about one year of stopping sowing, the component and structure of soil that once cultivated morel would be restored. In co-occurrence networks, some noteworthy bacterial microbes involved in nitrogen fixation and nitrification have been identified in soils with high morel yields, such as Arthrobacter, Bradyhizobium, Devosia, Pseudarthrobacter, Pseudolabrys, and Nitrospira. In contrast, in soils with low or no morel yield, some pathogenic fungi accounted for a high proportion, including Gibberella, Microidium, Penicillium, Sarocladium, Streptomyces, and Trichoderma. This study provided valuable information for the isolation and culturing of some beneficial microbes for morel cultivation in further study and, potentially, to harness the power of the microbiome to improve morel production and health.

Two new species Laccaria pseudoalba and L. subroseoalbescens are described and illustrated, based on morphological characteristics and molecular phylogenetic analysis. Two new records, Laccaria umbilicata and L. yunnanensis from Thailand, are also reported. Laccaria subroseoalbescens is characterized by small basidiomata, stipe equal with an enlarged base, and nearly subclavate, pale pink to light orange. Laccaria pseudoalba is characterized by pale orange to orange white pileus, has umbo when young on the pileus, and fistulose stipe of the pale to pastel red color. Phylogenetic analysis based on sequence data from rDNA internal transcribed spacer ITS1-5.8S-ITS2 rDNA (ITS), nuc 28S rDNA (28S), RNA polymerase II subunit 2 (rpb2), and translation elongation factor 1-α (tef1-α) are provided as further evidence. Molecular analysis confirms the phylogenetic positions of the two new species and two new records. The differences in characteristics of these two new species and closely related species are discussed herein.

Lyophyllum plays an important role in the natural ecosystem and has significant economic value. Some species of this genus have been cultivated in Asia, America, and Europe. This study describes four edible species of Lyophyllum, two of which were newly discovered. Lyophyllum edulis has a dark grayish orange pileus, a grayish orange upper part of the stipe, and globose, subglobose to broadly ellipsoid basidiospores, while L. sinense has a dark gray-orange when injured pileus, dark grayish orange points and lines on the stipe surface, and quadrangular to broadly fusiform basidiospores. Molecular phylogenetic analyses using the internal transcribed spacer ITS1-5.8S-ITS2 ribosomal RNA (ITS), the large subunit ribosomal RNA (LSU), the second-largest subunit of RNA polymerase II (rpb2), and translation elongation factor 1-alpha (tef1-α) indicated that L. edulis is related to L. shimeji, L. heimogu, and L. decastes, and L. sinense has an affinity to L. bulborhizum and L. nigrum. We also summarize the cultivation techniques of the two edible species, L. shimeji and L. decastes.

Two new species, Termitomyces tigrinus and T. yunnanensis are described based on specimens collected from southwestern China. Termitomyces yunnanensis is morphologically characterized by a conspicuously venose pileus surface that is grey, olive grey, light grey to greenish grey at center, light grey towards margin, and a cylindrical white stipe. Termitomyces tigrinus is morphologically characterized by a densely tomentose to tomentose-squamulose pileus showing alternating greyish white and dark grey zones, and a stipe that is bulbous at the base. The two new species are supported by phylogenetic analyses of combined nuclear rDNA internal transcribed spacer ITS1-5.8S-ITS2 rDNA (ITS), the mitochondrial rDNA small subunit (mrSSU) and the nuclear rDNA large subunit (nrLSU). The morphological variability of T. intermedius, including five specimens newly collected from Yunnan Province, China, is also discussed. The collections showed variability in colour of the stipe surface and in the shape of cheilocystidia when compared to the original description. Full descriptions of the two new species and of T. intermedius, as well as a taxonomic key to the 14 Termitomyces species reported from China are provided.

Urnula is a prominent and older genus within the family Sarcosomataceae. Its members are widely distributed and have very similar features in the field. This study proposes two novel Urnula species collected from Yunnan Province, China. Detailed descriptions, illustrations, and phylogenetic analyses are provided. Urnula ailaoshanensis grows on rotten wood surrounded by moss and is characterized by its brighter hymenial surface, wider asci, and longer ascospores. Urnula subcrateria was collected on the soil humus layer of a subtropical forest with many fallen leaves, mosses, and lichens. It is morphologically and molecularly related to Urnula craterium (Schwein.) Fr., but can easily be distinguished by its shorter stipe and smaller asci and ascospores.

As symbiotic mycorrhizal associates, species within the genus Laccaria play pivotal roles in forest ecosystems, specifically forming ectomycorrhizal relationships with the root systems of various plants. Some Laccaria species are recognized for their edibility, holding potential as a sustainable food source in the context of future food security and dietary diversification. In this study, the species diversity of Laccaria in Yunnan was investigated, and four novel species were identified. Their taxonomical positions and phylogenetic affinities were confirmed through phylogenetic analysis based on ITS, nrLSU, tef1-α, and rpb2 sequence data. Macro- and micro-morphological characteristics of the new species are also given here. Laccaria brownii sp. nov. has a dark to slightly desaturated orange pileus, stipe context broadly fistulose and soft orange, and relatively smaller cheilocystidia and pleurocystidia. Laccaria orangei sp. nov. has a hemispherical to paraboloid pileus, abundant narrowly clavate, flexuose, and branched cheilocystidia. Laccaria ruber sp. nov. pileus is red on the margin, clearly striate on the pileus surface, basidia clavate, mostly four-spored, rarely two-spored. Laccaria stipalba sp. nov. stipe surface is white, long sterigmata (4–13 μm × 2–3 μm), pleurocystidia narrowly clavate to subclavate, flexuose or mucronate, rarely branch. The descriptions, illustrations, and phylogenetic analysis results of the new taxa are provided. In addition, the new taxa are compared with closely related taxa.