This study proposes two new species and a new record in the Rhodocybe-Clitopilus clade, based on comprehensive morphological and molecular analyses. The nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2 (ITS), the large subunit ribosomal RNA gene (LSU), the RNA polymerase II second largest subunit (RPB2) and the translation elongation factor 1-alpha gene (TEF1), were employed to elucidate the relationships of Clitopilus and Rhodocybe. The first species, Clitopilus parasiticus, is capable of infecting the leaves of host plants in the genera Dryopteris and Oplismenus, exhibiting typical biotrophic behaviour while also demonstrating saprophytic growth on soil. Intraspecific comparisons were conducted, examining environmental factors as well as macro- and microscopic characteristics amongst individuals found on different plant hosts. Furthermore, this study reports the new saprophytic species, Rhodocybe zijinshanensis and provides a detailed description of Clitopilus baronii, a newly-recorded species in China.

Buchwaldoboletus xylophilus is an edible bolete species belonging to the family Boletaceae and the genus Buchwaldoboletus. It is found in tropical and subtropical regions, which are known for their rare wild resources. In this study, wild B. xylophilus was isolated and cultured, and its biological characteristics and artificial cultivation techniques were studied. The results show that the optimal carbon source, nitrogen source, and inorganic salt for the mycelium growth of B. xylophilus were maltose, ammonium tartrate, and magnesium sulfate, respectively. The most appropriate temperature was 28 °C, and the pH value was between 5 and 6. The most effective combination was determined via orthogonal experimentation, as follows: dextrose, ammonium nitrate, potassium dihydrogen phosphate, and 28 °C. The results of artificial cultivation in mushroom houses show that the mycelium of B. xylophilus was strong and grew well on the culture medium. The mycelial growth rate was 4.54 mm/d, and the fungus bags were filled about 50 days after inoculation. The primordia formed 9 to 14 days after covering with soil and the fruiting body matured in 6~8 days. The average yield of fresh mushrooms reached 131.07 ± 29.38 g/bag, and the average biological efficiency reached 28.48 ± 6.39%. In this study, artificial cultivation technology in respect of B. xylophilus in mushroom houses is reported for the first time. The fruiting bodies obtained through cultivation were identified using morphological and molecular biological methods. This technology offers benefits such as affordability, a brief cultivation cycle, substantial yields, and superior quality, making it ideal for industrial-scale and extensive cultivation.

Hevea brasiliensis (Willd. ex A.Juss.) Müll.Arg., the world’s primary source of natural rubber, faces increasing threats from emerging diseases in tropical cultivation regions. During recent field surveys in Yunnan and Hainan provinces of China, previously uncharacterized brown, water-soaked necrotic lesions were observed on tender stems and leaves of rubber trees. This study aimed to identify the causal pathogen, characterize its biological traits, and evaluate candidate fungicides for disease management. The pathogen was isolated via tissue explant methods and identified through morphological observation combined with multigene phylogenetic analyses based on the internal transcribed spacer (ITS) region, large subunit (LSU) ribosomal DNA, and cytochrome c oxidase subunits I and II (coxI and coxII) sequences. Pathogenicity was rigorously confirmed by fulfilling Koch’s postulates on rubber tree seedlings. The isolates produced spherical to ovoid, papillate sporangia, and phylogenetic reconstruction strongly supported clustering them with Phytopythium vexans. The pathogen grew optimally at 16–31 °C, with growth ceasing at 35 °C. Fungicide sensitivity assays revealed that metalaxyl exhibited the strongest inhibitory activity against mycelial growth, with half-maximal effective concentration (EC₅₀) values as low as 0.04 μg/mL. To our knowledge, this is the first report of P. vexans causing foliar and stem necrosis on H. brasiliensis. These findings provide a theoretical foundation for accurate disease diagnosis, epidemiological surveillance, and the development of effective chemical control strategies for rubber plantations.

Callistosporiaceae is a recently established family within the suborder Tricholomatineae, encompassing tricholomatoid, collybioid or pleurotoid morphological forms. While most species of this family exhibit a saprotrophic lifestyle and have been predominantly documented in Europe and Americas, records from Asia remain comparatively sparse. In this study, Pulchragaricus rhodophyllus gen. et sp. nov., discovered in a Pinaceae and Fagaceae mixed forest in southwestern China, is described based on a comprehensive approach integrating both multigene phylogenetic analyses and morphological methods. A concatenated dataset comprising nuclear ribosomal DNA (ITS, LSU) and protein-coding genes (rpb2, tef1-α) provides robust statistical support for the placement of Pulchragaricus within Callistosporiaceae. Morphologically, this new taxon is characterized by a tomentose and yellowish-brown pileus, pink to pinkish lamellae, a solid and basally tapering stipe, broadly ellipsoid to ellipsoid basidiospores, sparse and subclavate cheilocystidia, and plentiful clamp connections. This discovery not only broadens the known diversity and distribution of the poorly documented Chinese Callistosporiaceae, but also offers a potential clue for understanding the evolutionary origins of the ectomycorrhizal symbiosis within the family.

Boletaceae, a family of profound ecological influence and economic value, has been the subject of prolific taxonomic research over the past decade, with new taxa continually being discovered. In this study, Similiboletinus tomentopileatus gen. et sp. nov., collected from a tropical region of China, is proposed based on integrative morphological and phylogenetic analyses. Phylogenetic analyses of a multigene dataset (LSU-rpb2-tef1-α-atp6) strongly support the position of Similiboletinus within the Suillelloideae. Morphologically, it is characterized by a tomentose and yellow–brown pileus, a subdecurrent hymenophore, unchanging context when injured, a boletoid hymenophoral trama, a cutis-type pileipellis, and broadly ellipsoid to ovoid basidiospores. The identification of Similiboletinus further underscores the striking and largely unexplored diversity of Boletaceae within tropical China.