Fungal communities in Nelumbinis semen characterized by high-throughput sequencing

The diversity of endophytic fungi in Tartary buckwheat (Fagopyrum tataricum) and its correlation with flavonoids and phenotypic traits

Tartary buckwheat (Fagopyrum tataricum) is a significant medicinal crop, with flavonoids serving as a crucial measure of its quality. Presently, the artificial cultivation of Tartary buckwheat yields low results, and the quality varies across different origins. Therefore, it is imperative to identify an effective method to enhance the yield and quality of buckwheat. Endophytic fungi reside within plants and form a mutually beneficial symbiotic relationship, aiding plants in nutrient absorption, promoting host growth, and improving secondary metabolites akin to the host. In this study, high-throughput sequencing technology was employed to assess the diversity of endophytic fungi in Tartary buckwheat. Subsequently, a correlation analysis was performed between fungi and metabolites, revealing potential increases in flavonoid content due to endophytic fungi such as Bipolaris, Hymenula, and Colletotrichum. Additionally, a correlation analysis between fungi and phenotypic traits unveiled the potential influence of endophytic fungi such as Bipolaris, Buckleyzyma, and Trichosporon on the phenotypic traits of Tartary buckwheat. Notably, the endophytic fungi of the Bipolaris genus exhibited the potential to elevate the content of Tartary buckwheat metabolites and enhance crop growth. Consequently, this study successfully identified the resources of endophytic fungi in Tartary buckwheat, explored potential functional endophytic fungi, and laid a scientific foundation for future implementation of biological fertilizers in improving the quality and growth of Tartary buckwheat.

Single-Molecule Real-Time Sequencing to Explore the Mycobiome Diversity in Malt

This study determined the composition of fungal communities and characterized the enriched fungal species in raw and roasted malts via the third-generation PacBio-based full-length single-molecule real-time (SMRT) sequencing of the full-length amplicon of the internal transcribed spacer (ITS) region. In total, one kingdom, six phyla, 23 classes, 56 orders, 120 families, 188 genera, 333 species, and 780 operational taxonomic units (OTUs) were detected with satisfactory sequencing depth and sample size. Wickerhamomyces (56%), Cyberlindnera (15%), Dipodascus (12%), and Candida (6.1%) were characterized as the dominant genera in the raw malts, and Aspergillus (35%), Dipodascus (21%), Wickerhamomyces (11%), and Candida (3.5%) in the roasted malts. Aspergillus proliferans, Aspergillus penicillioides, and Wickerhamomyces anomalus represented the crucial biomarkers causing intergroup differences. Correlation analysis regarding environmental factors indicated that the water activity (a_w) of the samples affected the composition of the fungal communities in the malts. In practice, special attention should be paid to the mycotoxin-producing fungi, as well as other fungal genera that are inversely correlated with their growth, to ensure the safe use of malt and its end products.

IMPORTANCE Fungal contamination and secondary metabolite accumulation in agricultural products represent a global food safety challenge. Although high-throughput sequencing (HTS) is beneficial for explaining fungal communities, it presents disadvantages, such as short reads, species-level resolution, and uncertain identification. This work represents the first attempt to characterize the fungal community diversity, with a particular focus on mycotoxin-producing fungi, in malt via the third-generation PacBio-based full-length SMRT sequencing of the ITS region, aiming to explore and compare the differences between the fungal communities of raw and roasted malts. The research is beneficial for developing effective biological control and conservation measures, including improving the roasting conditions, monitoring the environmental humidity and a_w, and effectively eliminating and degrading fungi in the industry chain according to the diverse fungal communities determined, for the safe use of malts and their end products, such as beers. In addition, the third-generation SMRT sequencing technology allows highly efficient analysis of fungal community diversity in complex matrices, yielding fast, high-resolution long reads at the species level. It can be extended to different research fields, updating modern molecular methodology and bioinformatics databases.