Latest ArticlesIn order to clarify the genetic diversity and population genetic structure of Botrytis cinerea on solanaceous vegetables in Qinghai Province, 213 strains of Botrytis cinerea isolated from solanaceous vegetables were analyzed by ISSR molecular marker technology. A total of 243 polymorphic loci was amplified by 12 primers. Cluster analysis based on ISSR data showed that 213 strains could be divided into 9 groups at the level of 0.65 similarity coefficient. The Nei's gene diversity index (H) was 0.437 0, the percentage of polymorphic loci (P) was 100%, the effective number of alleles (Ne) was 1.807 3, the Shannon's information index (I) was 0.625 6, and the observed number of alleles was 2.000 0. The genetic differentiation coefficient (Gst) was 0.203 6, and the gene flow (Nm) was 1.956 4. The genetic variation of B. cinerea mainly occurred within the population (85%). Based on the similarity coefficient of 0.89, the five geographical populations could be divided into two main groups and three subgroups. The PCoA analysis reveals that although there is some degree of overlap among the populations, they generally exhibit a geographically clustery tendency. The genetic variation among the three host populations is only 2%. Compared with the geographical origin population, the population genetic distance is close and the genetic similarity is high. In the PCoA analysis, most of the individual strains formed a close cross, and a small number of strains were discrete.
The C2H2 zinc finger transcription factor AZF1 in fungi has multiple biological functions such as regulating growth and development, secondary metabolism synthesis, and pathogenicity, however, the functions of this homologous protein in Aspergillus flavus is still unclear. Homology comparison revealed that the protein encoded by AFLA_054800 shares 50% homology with the AZF1 protein in Trichoderma reesei, and it was named AflAZF1. This study found that the colony size of the AflAZF1 gene deletion strain (ΔAflAZF1) was not significantly different from that of the wild type, but the conidiation was significantly reduced, and the sclerotia could not form. The production of aflatoxin AFB1 in the ΔAflAZF1 strain was significantly increased. When glucose, arabinose, mannose, sucrose, and xylose were used as carbon sources, the conidiation ability of the ΔAflAZF1 strain was significantly decreased, but it was significantly increased in lactose and glycerol. Additionally, under pH 5 and pH 11 conditions, the number of conidia in the ΔAflAZF1 strain was significantly lower than that in the wild type. The results indicate that AflAZF1 not only regulates conidiation and sclerotial formation and AFB1 biosynthesis, but also modulates the utilization of different carbon sources and adaptation to extreme pH conditions by affecting conidiation ability. This discovery not only reveals the key role of AflAZF1 in the growth and development and toxin synthesis of A. flavus, but also provides a theoretical basis for the prevention and control of A. flavus contamination and the development of new biological control strategies.
A new disease was found on Vernicia fordii with symptom of root rot in Dushan, Guizhou Province. The disease occurred most seriously at growth stage (May to July), primarily affecting the roots. The diseased plants initially showed wilting and leaves fade green to withered until plant death. The fungal community composition of the rhizosphere soil was analyzed from healthy and diseased plants. The result showed that mainly dominant phyla and genera in the rhizosphere soil of diseased and healthy plants were similar, but the relative abundance was absolutely different. Moreover, the genus Fusarium causing a wide range of plant diseases only appeared in the fungal community of rhizosphere soil of diseased V. fordii, with relative abundance accounting for 2.44%. The pathogens were isolated and purified through tissue isolation. Ten strains were isolated from the healthy junction of V. fordii rhizome suffering from typical root rot. Among them, strain AX-2 induced typical symptoms of root rot after being back-inoculated to the seedlings of V. fordii. The pathogen was subsequently isolated from the roots and stems of diseased plants. Its morphological characteristics were found to be consistent with those of the pathogen isolated from the field. Molecular identification further verified that this strain was identical to AX-2. Morphological characteristics and multi-loci (ITS+tef1-α+rpb2+CaM+tub2) phylogeny classified AX-2 as Fusarium foetens. The species is firstly reported as the pathogen of root rot in V. fordii. This study provides a theoretical foundation for investigating the infection characteristics and control strategies of root rot disease in V. fordii.
The prevention effects of Hericium coralloides polysaccharides (HCP) on chronic colitis and the impact of HCP on gut microbial communities in mice were investigated. Sixty mices were randomly divided into six groups: blank control (CK), model control (MC), positive control (PC), low-dose HCP (L-HCP), medium-dose HCP (M-HCP), and high-dose HCP (H-HCP). Biochemical indicators of serum, colonic tissue and histopathological sections were compared among these groups, and 16S rRNA high-throughput sequencing was used to analyze the relative abundance and the diversity of the intestinal microflora at the phyla and class levels. Results showed that HCP significantly reduced the levels of serum interleukin-1β (IL-1β), serum interleukin-2 (IL-2), serum interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in the serum, and decreased the levels of the Toll-like receptor 4 (TLR4), cysteine protease 1 (Casp-1), apoptosis-associated speck-like protein (ASC) and phosphorylated p65 protein (pp65) in colonic tissue. The 16S rRNA sequencing showed that HCP significantly increased the α-diversity indices Chao1, Shannon, and observed species, reduced the Simpson index, and regulated the abundance of Bacteroides and Firmicutes, thereby reducing colonic tissue damage. In conclusion, HCP can prevent DSS-induced chronic colitis and possesses potential utilization value in the field of functional food.
The Xinjiang mining area faces a severe soil salinization problem that restricts plant growth. Addressing saline-alkali soil is crucial for ecological restoration in the mining area. Dark septate endophytes (DSE) can enhance plant stress resistance and are important for ecosystem restoration and promoting vegetation restoration. The DSE in the roots of the dominant plant Suaeda salsa in unmined areas, vegetation reclamation areas, and undisturbed area without reclamation around the Hongshaquan saline-alkali mining area in Xinjiang are investigated. DSE micromorphology and physiological and biochemical responses under varying NaCl concentrations, and the salt tolerance characteristics of plant root symbiotic DSE are explored, aiming at providing a theoretical basis for ecological restoration in this region. The study found that S. salsa from different sampling sites in the area could form a favorable symbiotic relationship with DSE, and 23 DSE strains were isolated from S. salsa roots. Following initial screening for salt tolerance, four strains were selected. Among these, Chaetomium globosum maintained growth under 3 mol/L NaCl stress, exhibiting significantly superior biomass, reduced glutathione content, and sporulation capacity compared to the other strains. The remaining three Alternaria spp. strains displayed distinct microstructural alterations under 2 mol/L NaCl salt stress, including a significant increase in mycelium diameter, shortened septum spacing, and a wrinkled surface. This structural differentiation may represent their adaptive response to salt stress. Furthermore, these three DSE strains mitigated salt stress damage through physiological mechanisms such as increasing soluble protein content and enhancing superoxide dismutase (SOD) and catalase (CAT) activities. The results provide a theoretical basis for screening salt-tolerant microorganisms and applying microbial reclamation technology in saline-alkali mining areas in Xinjiang.
Arbuscular mycorrhiza (AM) plays crucial roles in terrestrial ecosystems. This study employed high-throughput sequencing to analyze the structure and diversity, ecological distribution patterns, and relationships with soil factors of AM fungal communities in the rhizosphere soil and roots of Allium ramosum at different elevations on Chunkun Mountain in North China. In total, 1 431 amplicon sequence variants (ASVs) belonging to 95 AM fungal virtual taxa (VTs) encompassing 7 families and 8 genera were obtained from rhizosphere soil and root samples. Among these, the genus Ambispora was exclusively detected in the rhizosphere soil. The genus with the highest relative abundance was Glomus, and Claroideoglomus was the next. Altitude significantly influenced the diversity of AM fungal communities in the rhizosphere soil and roots of A. ramosum. The Chao1 indices for both roots and rhizosphere soil, together with the root Shannon index, peaked in the middle altitude range, whereas the Shannon index of rhizosphere soil reached its highest value in the high-altitude range. The AM fungal alpha diversity index in the rhizosphere soil was significantly higher than that in the roots (P<0.05), suggesting that roots exhibit selectivity towards symbiotic AM fungi. The results of the redundancy analysis (RDA) and the Monte Carlo permutation test indicated that soil organic carbon is a key driving factor for the arbuscular mycorrhizal (AM) fungal communities in the rhizosphere soil and roots of A. ramosum (P<0.001). Total phosphorus also had highly significant influence on the AM fungal community in rhizosphere soil (P<0.001). This study provides reference for the further development and utilization of A. ramosum.
Fungal drug-resistance poses a serious threat to global public health, with mechanisms encompassing genetic mutations, epigenetic regulation, and genomic instability. Chromosomal aneuploidy has recently emerged as a critical driver of resistance. This review comprehensively summarizes the molecular mechanisms by which aneuploidy mediates resistance in pathogenic fungi, including gene dosage effects, transcriptional dysregulation, and metabolic pathway interference. Key findings reveal that Candida albicans upregulates efflux pump genes (CDR1/2) through chromosomal duplication, while Aspergillus fumigatus reduces azole susceptibility via cyp51A copy number amplification. In Cryptococcus neoformans, stress-induced aneuploidy exhibits dynamic plasticity, rapidly emerging under drug pressure and reverting upon withdrawal. Technologies such as whole genome sequencing (WGS) and qPCR have proven pivotal to be for clinical resistance prediction and therapeutic monitoring, yet cost and technical barriers hinder their widespread implementation. Future research should focus on deciphering the interplay between aneuploidy, epigenetic modifications, and mutational accumulation, alongside developing therapeutic strategies to correct aneuploidy and optimize rapid diagnostics for precision of medicine application. By synthesizing cross-species evidence, this review advances our understanding of fungal resistance mechanisms and informs the development of novel interventions.
The informal term ‘dahongjun' or ‘big red mushroom' is a group of red-coloured russulas widely collected and consumed in southern China, originally mistakenly recognized as the European Russula vinosa. Russula griseocarnosa was described from China in 2009, and since then, it has become the only available scientific name for ‘dahongjun'. Nevertheless, several lineages exist within this complex, and whether these lineages represent real species is still an open question. Sampling in major producing areas of ‘dahongjun' and phylogenetic species recognition using multi-locus data were conducted. Besides R. griseocarnosa nine additional species were identified under the commercial name ‘dahongjun', including R. dhakuriana, R. quercina, R. purpureozonata, R. yanheensis and a new species sister to R. griseocarnosa here described as R. occulta. The others were undescribed species close to R. laricina, R. lepida, and R. purpureozonata respectively. Six evolutionary lineages within R. griseocarnosa were defined by genealogical concordance phylogenetic species recognition based on five-locus DNA data. Conflicts among different genealogies suggested that R. griseocarnosa is best considered as a single phylogenetic species, comprising several infraspecific taxa. Lower coverage whole genome sequencing of R. griseocarnosa holotype discovered that its three individuals belong to three different clades. Lectotypification was made using one of the three individuals. A new variety R. griseocarnosa var. ailaoshanensis is described to name one of the terminal clades that is mainly distributed in Ailao Mountains. This variety differs morphologically from the type variety in its nearly white context, bigger spores and more inflated hyphae in the pileipellis. The morphological and molecular data provided in this study are helpful to identify wild edible mushrooms of Russula subgen. Russula.
The chemical constituents of Morchella eximia were isolated by modern chromatographic separation techniques, and the structures were elucidated by nuclear magnetic resonance (NMR), mass spectrometry (MS), etc. Subsequently, a HPLC method was established for determining the ergosterol content in the fruiting bodies of different species of morels. This method was applied to comparatively analyze the ergosterol content in different growth stages (juvenile, mature, and aging stages) of the fruiting bodies of three cultivated species of morels (Morchella importuna, M. sextelata and M. eximia). In total, 13 compounds were isolated and identified from the fruiting bodies of M. eximia, including 5 ergosterol-related compounds. Among these, compounds 2, 9, 10 and 12 were isolated from the genus Morchella for the first time. HPLC analysis revealed significant differences in ergosterol content in the fruiting bodies of different species and growth stages of morels. The highest content was found in the juvenile fruiting bodies of the three species [(1.647±0.013)-(2.289±0.011) mg/g], however the content comparatively decreased in the mature stage. M. sextelata had the highest content [(1.796± 0.008) mg/g], while M. importuna had the lowest [(1.250±0.004) mg/g] in the mature stage. These findings are significant for the further development, utilization, and quality evaluation of morels.
A manganese-oxidizing fungal strain designated as ZL8-1 was isolated from the soil in a manganese mining area and identified as Aspergillus flavipes based on morphological characteristics and molecular phylogenetic method. The strain exhibited rapid growth, reaching colony diameter of 5.44 cm on AY medium in 7 days of incubation. A. flavipes ZL8-1 demonstrated strong manganese tolerance, withstanding concentrations up to 8 mmol/L, and showed minimal growth inhibition at 1-4 mmol/L Mn2+. The highest manganese removal efficiency of 77.50% was achieved at concentration of 1 mmol/L over 22-day period. A. flavipes ZL8-1 could be regarded as a promising microbial resource for manganese bioremediation.