Shanping Wan’s research while affiliated with Yunnan Agricultural University and other places

Background During surveys of hypogeous fungi in the Hengduan Mountains, south-western China, three specimens of the genus Truncocolumella were discovered in Sichuan Province. New information Morphological and molecular analyses revealed that the collections represent a new species, Truncocolumella pseudocolumella. This article describes the new species and discusses its relationship with the other two members of the genus.

CITATION: Wang, R.;† Dong, G.†; Li, Y.; Wang, R.; Yang, S.; Yuan, J.; Xie, X.; Shi, X.; Yu, J.; Pérez-Moreno, J.; Fu-qiang Y.; Shanping, W. Three New Truffle Species (Tuber, Tuberaceae, Pezizales, and Ascomycota) from Yunnan, China, and Multigen Phylogenetic Arrangement within the Melanosporum Group. J. Fungi 2024, 10, 640. † These authors contributed equally to this work. ABSTRACT: Based on a multi-locus phylogeny of a combined dataset of ITS, LSU, tef1-α, and rpb2 and comprehensive morphological analyses, we describe three new species from the Melanosporum group of genus Tuber and synonymize T. pseudobrumale and T. melanoexcavatum. Phylogenetically, the three newly described species, T. yunnanense, T. melanoumbilicatum and T. microexcavatum, differ significantly in genetic distance from any previously known species. Morphologically, T. yunnanense is distinctly different from its closest phylogenetically related species, T. longispinosum, due to its long shuttle-shape spores (average the ratio of spore length to spore width for all spores (Qm) = 1.74). Tuber melanoumbilicatum differs from the other species in having a cavity and long shuttle-shaped spores (Qm = 1.65). Although T. microexcavatum sampled ascomata have relatively low maturity, they can be distinguished from its closely related species T. pseudobrumale by the ascomata size, surface warts, and spore number per asci; additionally, phylogenetic analysis supports it as a new species. In addition, molecular analysis from 22 newly collected specimens and Genebank data indicate that T. pseudobru-male and T. melanoexcavatum are clustered into a single well-supported clade (Bootstrap (BS) = 100, posterior probabilities (PP) = 1.0); and morphological characteristics do not differ. Therefore, based on the above evidence and publication dates, we conclude that T. melanoexcavatum is a synonym of T. pseudobrumale. By taking into account current knowledge and combining the molecular, multigene phylogenetic clade arrangement and morphological data, we propose that the Melanosporum group should be divided into four subgroups. Diagnostic morphological features and an identification key of all known species in the Melanosporum group are also included. Finally, we also provide some additions to the knowledge of the characterization of T. pseudobrumale, T. variabilisporum, and T. pseudohimalayense included in subgroup 1 of the Melanosporum group.

Three new species of Tuber, T. albicavum, T. laojunshanense, and T. umbilicicavatum belonging to the Puberulum phylogroup, are described based on specimens collected in alpine Abies forests at 3600–4000 m, Northwest Yunnan, China. T. albicavum is distinguished by its ascomata with a single chamber of 0.5–1.8 cm diameter, with an apical opening of 0.2–0.6 cm in diameter, and light golden-brown alveolate reticulate ascospores up to 30 μm in length; T. laojunshanense is characterized by having ascomata with a slightly tomentose surface, sometimes with a white navel, a relatively thick peridium, up to 280 µm, and yellow-brown spores with alveolate reticulate ornamentation, up to 34 µm in length; T. umbilicicavatum is characterized by smooth ascomata with a distinct white navel, a relatively thin peridium, up to 110 µm, and golden or golden-brown alveolate reticulate ascospores, up to 40 μm in length. The molecular analysis of the internal transcribed spacer region also supports that these three new species differ from previously described Tuber species.

Background and aims Mycorrhizal fungi-released phosphatases have long been claimed pivotal to mobilize soil organic phosphorus (P). We hypothesized that ectomycorrhizal (ECM) fungi, compared with their saprotrophic ancestors, evolved adaptive strategies to enhance the release of phosphatases to meet the P demand of ECM fungi and their host plants. Methods We analyzed genes potentially encoding secreted phosphatases in 103 fungal species, ECM fungi hyphae associated- and ectomycorrhizosphere phosphatase enzyme activities, and gene expression of Lactarius spp. and Laccaria bicolor fungi-secreted phosphatases during ECM formation. We also determined ectomycorrhizosphere abundance of bacterial phosphatase genes, and analyzed Pinus yunnanensis–Lactarius deliciosus ectomycorrhiza-associated P-mobilizing bacteria. Results We found that during transition from saprotrophy to ECM symbiosis, genes encoding fungal-secreted phosphatases did not manifest adaptive or convergent evolution. Among 10 genes potentially encoding secreted fungal phosphatases in Lactarius spp. and Laccaria bicolor, only two were up-regulated during ECM formation. Furthermore, unlike saprotrophic fungi, pure-cultured ECM fungi hyphae released very few or no phosphatases to the surroundings, while ECMs generally increased the phosphatase activities in the ectomycorrhizosphere under glasshouse conditions. Additionally, ECM-associated bacteria exhibited an increased abundance of P-cycling genes in the ectomycorrhizosphere under both glasshouse and field conditions. A substantial part of culturable bacteria from ECM tips hydrolyzed organic P and promoted fungal P acquisition. Conclusion We found no evidence for adaptive evolution of secreted phosphatases in ECM fungi; some ECM fungi may not even release phosphatases, and ECM-associated bacteria likely play a pivotal role in ECM-promoted organic P hydrolysis and plant P acquisition.

Background and aims Mycorrhizal fungi-released phosphatases have long been claimed pivotal to mobilize soil organic phosphorus (P). We hypothesized that ectomycorrhizal (ECM) fungi, compared with their saprotrophic ancestors, evolved adaptive strategies to enhance the release of phosphatases to meet the P demand of ECM fungi and their host plants. Methods We analyzed genes potentially encoding secreted phosphatases in 103 fungal species, ECM fungi hyphae associated- and ectomycorrhizosphere phosphatase enzyme activities, and gene expression of Lactarius spp. and Laccaria bicolor fungi-secreted phosphatases during ECM formation. We also determined ectomycorrhizosphere abundance of bacterial phosphatase genes, and analyzed Pinus yunnanensis–Lactarius deliciosus ectomycorrhiza-associated P-mobilizing bacteria. Results We found that during transition from saprotrophy to ECM symbiosis, genes encoding fungal-secreted phosphatases did not manifest adaptive or convergent evolution. Among 10 genes potentially encoding secreted fungal phosphatases in Lactarius spp. and Laccaria bicolor, only two were up-regulated during ECM formation. Furthermore, unlike saprotrophic fungi, pure-cultured ECM fungi hyphae released very few or no phosphatases to the surroundings, while ECMs generally increased the phosphatase activities in the ectomycorrhizosphere under glasshouse conditions. Additionally, ECM-associated bacteria exhibited an increased abundance of P-cycling genes in the ectomycorrhizosphere under both glasshouse and field conditions. A substantial part of culturable bacteria from ECM tips hydrolyzed organic P and promoted fungal P acquisition. Conclusion We found no evidence for adaptive evolution of secreted phosphatases in ECM fungi; some ECM fungi may not even release phosphatases, and ECM-associated bacteria likely play a pivotal role in ECM-promoted organic P hydrolysis and plant P acquisition.

Ectomycorrhizal (EM) fungi play important roles in nutrient cycling and plant community establishment in forest ecosystems. Effects of EM formation on global alterations of the transcriptome and metabolome during plant-fungal interaction and the key metabolites involved in EM development are largely unknown. Here, dual RNA-Seq and untargeted metabolomic analyses were used to reveal stage-specific and core responses of Pinus yunnanensis and Lactarius deliciosus during mycorrhizal colonization. We found that L. deliciosus colonization in P. yunnanensis roots induced different transcriptional changes across three interaction stages, with a small core of genes consistently regulated at all stages. Concentrations of retinol (vitamin A) and retinoic acid increased while that of B group vitamins decreased during EM formation , which was coordinately regulated by these two plant-fungus partners, with L. deliciosus possibly playing a dominant role. Exogenous retinol altered the diameter and mantle thickness of P. yunnanensis-L. deliciosus EM tips and affected host plant growth and phosphorus acquisition. In the absence of L. deliciosus, exogenous retinol increased the root diameter and the number of root tips of P. yunnanensis. Furthermore , the concentration of auxin increased, but that of abscisic acid decreased during EM formation, and the genes involved in plant hormone signal transduction were gradually activated, and auxin and cytokinin signal transduction potentially played a positive role in this EM symbiosis. In conclusion, we propose that the interaction of P. yunnanensis and L. deliciosus alters vitamin metabolism, which may further affect plant hormone biosynthesis and signal transduction, modulating root morphology and EM traits.

Black truffles and white truffles are widely studied around the world, but their effects on plant growth and physiological responses, and on the mycorrhizosphere bacterial community of the host plant remain unclear. Here, mycorrhizal colonization of Castanopsis rockii by Tuber indicum (Chinese black truffle) and T. lijiangense (Chinese white truffle), respectively, was induced in a greenhouse study, and their effects on host growth, physiological responses and mycorrhizosphere bacterial communities were compared. The results show that colonization of both Tuber species significantly increased leaf photosynthetic rate, leaf P concentration and mycorrhizosphere acid phosphatase activity, as well as richness of mycorrhizosphere bacterial communities of C. rockii seedlings. However, T. indicum colonization on the one hand significantly decreased tartrate content, bacterial acid phosphatase, phoC gene abundance in the mycorrhizosphere, and peroxidase (POD) activity of ectomycorrhizal root tips, but on the other hand increased mycorrhizosphere pH and superoxide dismutase (SOD) of ectomycorrhizal root tips, compared to T. lijiangense colonization. Moreover, principal coordinate and β-diversity analyses show significant differences in mycorrhizosphere bacterial community composition between T. indicum and T. lijiangese colonized C. rockii seedlings. Finally, the relative abundance of the bacterium Agromyces cerinus significantly correlated to mycorrhizosphere acid phosphatase activity and leaf P concentration, suggesting that this bacterium might play an important role in P mobilization and acquisition. Overall, these results suggest that T. indicum and T. lijiangense differently regulate their host plant’s physiological responses and mycorrhizosphere bacterial community.

A new Choiromyces species was discovered at local wild mushroom markets in Songpan County, Sichuan, southwest China where it has been considered as a Chinese white truffle. Based on both morphological and phylogenetic analyses, the collection was described as Choiromyces si-chuanensis sp. nov. This study confirms the occurrence of members of Choiromyces in China. In addition , the mycorrhizal synthesis via spore inoculation between C. sichuanensis and Pinus armandii or two Picea species of Pi. likiangensis and Pi. crassifolia was attempted in a greenhouse. Both mor-phoanatomical and molecular analyses evidenced well-developed mycorrhization between C. si-chuanensis and P. armandii, but not in Picea seedlings. Our current study provides data about the species diversity and mycorrhizal research of this genus for further studies. In addition, a successful mycorrhization between C. sichuanensis and selected tree species, irrespective of Pinus genus or other plant species, would broaden the set of species for a successful mycorrhization in greenhouse conditions and potential outplanting for cultivation purposes.

Tuber qujingense and T. songlu are described as new species based on both phylogenetic and morphological analyses. Phy-logenetically, these two species are clearly distinct from described species of Tuber. Morphologically, these two species have whitish smooth ascomata, pubescent and prosenchymatous peridium and 1-4 spored asci; however, T. qujingense is characterized by its fusiform ascospores and taller alveolar walls (4.5-11 µm) while T. songlu has larger ellipsoid ascospores and lower alveolar walls (1-7 µm).

Pachyphlodes atropurpurea and P. excavata are described as new species of truffles based on both phylogenetic and morphological analyses. Phylogenetically these two species are clearly distinct from described species of Pachyphlodes. Morphologically, P. atropurpurea is characterized by subglobose, purple black ascomata, and ascospores with acute-tipped spines. P. excavata is characterized by its ascomata with an obvious basal and internal cavity and slender fusiform asci (150-180 × 30-40 μm).