With the growing numbers of the urban population, an increasing number of commuters have relied on subway systems for rapid transportation in daily life. Analyzing the temporal distribution of air microbiomes in subway environments is crucial for the assessment and monitoring of air quality in the subway system, especially with regard to public health. This study employed culture-independent metabarcode sequencing to analyze bacterial diversity and variations in bacterial compositions associated with bioaerosols collected from a subway station in Bangkok over a four-month period. The bacteria obtained were found to consist primarily of Proteobacteria, Firmicutes, and Actinobacteria, with variations at the family, genus, and species levels among samples obtained in different months. The vast majority of these bacteria are most likely derived from outside environments and human body sources. Many of the bacteria found in Bangkok subway station were also identified as "core microorganisms" of subway environments around the world, as suggested by the MetaSUB Consortium. The diversity of bacterial communities was shown to be influenced by several air quality variables, especially ambient temperature and the quantity of particulate matters, which showed positive correlations with several bacterial species such as Acinetobacter lwoffii, Staphylococcus spp., and Moraxella osloensis. In addition, metabolic profiles inferred from metabarcode-derived bacterial diversity showed significant variations across different sampling times and sites and can be used as a starting point to further explore the functional roles of specific groups of bacteria in the subway environment. This study thus introduced the information required for surveillance of microbiological impacts and their contributions to the well-being of subway commuters in Bangkok.

Rust fungi in the order Pucciniales represent one of the largest groups of phytopathogens, which occur on mosses, ferns to advanced monocots and dicots. Seven suborders and 18 families have been reported so far, however recent phylogenetic studies have revealed para- or polyphyly of several morphologically defined suborders and families, particularly in Melampsorineae. In this study, a comprehensive phylogenetic framework was constructed based on a molecular phylogeny inferred from rDNA sequences of 160 species belonging to 16 genera in Melampsorineae (i.e. Chrysomyxa, Cerospora, Coleopuccinia, Coleosporium, Cronartium, Hylospora, Melampsora, Melampsorella, Melampsoridium, Milesina, Naohidemyces, Pucciniastrum, Quasipucciniastrum, Rossmanomyces, Thekopsora, Uredinopsis). Our phylogenetic inference indicated that 13 genera are monophyletic with strong supports, while Pucciniastrum is apparently polyphyletic. A new genus, Nothopucciniastrum was therefore established and segregated from Pucciniastrum, with ten new combinations proposed. At the family level, this study further demonstrates the importance of applying morphologies of spore-producing structures (basidia, spermogonia, aecia, uredinia and telia) in higher rank taxonomy, while those traditionally applied spore morphologies (basidiospores, spermatia, aeciospores, urediniospores and teliospores) represent later diverged characters that are more suitable for the taxonomy at generic and species levels. Three new families, Hyalopsoraceae, Nothopucciniastraceae and Thekopsoraceae were proposed based on phylogenetic and morphological distinctions, towards a further revision of Pucciniales in line with the phylogenetic relationships.

Armillaria species have a global distribution and play various roles in the natural ecosystems, e.g., pathogens, decomposers, and mycorrhizal associates. However, their taxonomic boundaries, speciation processes, and origin are poorly understood. Here, we used a phylogenetic approach with 358 samplings from Europe, East Asia, and North America to delimit the species boundaries and to discern the evolutionary forces underpinning divergence and evolution. Three species delimitation methods indicated multiple unrecognized phylogenetic species, and biological species recognition did not reflect the natural evolutionary relationships within Armillaria; for instance, biological species of A. mellea and D. tabescens are divergent and cryptic species/lineages exist associated with their geographic distributions in Europe, North America, and East Asia. While the species-rich and divergent Gallica superclade might represent three phylogenetic species (PS I, PS II, and A. nabsnona) that undergo speciation. The PS II contained four lineages with cryptic diversity associated with the geographic distribution. The genus Armillaria likely originated from East Asia around 21.8 Mya in early Miocene when Boreotropical flora (56–33.9 Mya) and the Bering land bridge might have facilitated transcontinental dispersal of Armillaria species. The Gallica superclade arose at 9.1 Mya and the concurrent vicariance events of Bering Strait opening and the uplift of the northern Tibetan plateau might be important factors in driving the lineage divergence.

Leptosphaerulina leaf blight occurs on most turfgrasses. Hitherto, Leptosphaerulina species associated with this disease include L. americana, L. argentinensis, L. australis, and L. trifolii. However, following Koch’s postulates, L. australis was confirmed as saprobes but not pathogens, and the other three species have not been tested. The pathogenicity of Leptosphaerulina spp. is still questionable. In this study, we isolated 19 Leptosphaerulina strains from diseased golf turfgrasses in China, and they were identified as L. gaeumannii, L. saccharicola, and a new species, L. macrospora, through multilocus (ITS, 28S, rpb2, and tub2) phylogenetic analyses and morphological observations. Pathogenicity test revealed that the three Leptosphaerulina species identified in this study cannot infect live/healthy turfgrass tissues of Poa pratensis and Agrostis stolonifera and only produced pseudothecia on the dead leaves of stressed seedlings. Considering the results of pathogenicity tests in this and previous studies, we speculate that most Leptosphaerulina species isolated from diseased turfgrass are not pathogens but saprobes. Applying proper management practices to prevent severe turfgrass stress is a key measure to reduce or eliminate the effects of Leptosphaerulina on golf turfgrass.

Emerging pathogen races spreading via long‐distance migration increasingly threaten global agricultural ecosystems. Understanding how pathogens migrate and adapt to new hosts via virulence evolution is crucial for developing strategies to mitigate future crop damage. Here we performed biosurveillance of Puccinia polysora , a global fungal pathogen causing southern corn rust (SCR), across China, Thailand and the Philippines. By analysing 193 field transcriptomic data, we detected both epidemic and endemic lineages co‐circulating in each country and elucidated the crucial role of host selection in driving the diversification of endemic lineages. Gene flow assessments and trajectory tracking indicated that the SCR infection source in northern China is likely of domestic origin and pathogen migration from the Philippines/Thailand into China is restricted to Hainan, coastal Guangdong and southern Yunnan. We detected country‐specific variants in 32 effector genes, with AvrRppC exhibiting the strongest positive selection. A phylogenetically distinct Luzon Island lineage (Philippines), carrying a novel AvrRppC allele capable of overcoming RppC ‐mediated resistance and represents a potentially invasive threat. Finally, we reviewed the global migration history of P. polysora in light of our findings. Our work represents the first step toward establishing an international surveillance network for P. polysora and emphasised a comprehensive control strategy integrating local governance and invasion prevention of international races.