Many Isaria-like species have recently been moved into more appropriate genera. However, more robust molecular phylogenetic analyses are still required for Isaria-like fungi to ensure accurate taxonomic identification. We analyzed these Isaria-like strains using multi-gene phylogenetics. Cryptic diversity was discovered in several Isaria farinosa strains, and two new species, Samsoniella pseudogunnii and S. pupicola, are proposed. Our results reveal that more attention needs to be paid to cryptic intraspecific diversity across different isolates and genotypes of the Isaria-like species, some of which will need to be transferred to Samsoniella. Interestingly, S. hepiali, with a very broad host distribution, has been widely used as a medicinal and edible cordycipitoid fungus.

Samsoniella species have been often found in the forest habitat and rarely found in special karst eco-environments, such as Tiankeng, valleys and caves. In this research, eleven cordyceps specimens were collected from Mayao River Valley. A known species (S. haniana) and two new species (S. duyunensis and S. vallis) were established and described according to a multilocus phylogenetic analysis and morphological characteristics. Our results provide insight that the richness of Samsoniella species in karst eco-environments and further attention should be paid to entomopathogenic fungi in such habitats.

The karst region in southwestern China is one of the biodiversity hotspots in the world with rich fungal diversity but under-studied. Four fungal species belonging to Chlorocillium (Clavicipitaceae) and Gamszarella (Cordycipitaceae) were isolated from dead spiders. Morphological comparisons, phylogenetic analyses and a PHI analysis based on multigene datasets support the establishment of these new species viz., Chlorocillium guizhouensesp. nov., C. vallensesp. nov., Gamszarella sinensissp. nov., and G. vallensissp. nov. are introduced. A new genus, Neogamszarella, is proposed to accommodate Gamszarella antillana, which is phylogenetically distinct from Gamszarellas. str. Our results revealed that further attention needs to be paid to the diversity of araneogenous fungi in the karst regions of southwestern China.

The karst regions of southwest China are rich in biodiversity and have critically threatened ecosystems, harboring unique species that could be new to science. During the investigations of arthropods associated-fungi, several fungal strains were collected. Among these, three new species, Conoideocrella tiankengensissp. nov. (Clavicipitaceae), Ovicillium zunyiensesp. nov. (Bionectriaceae) and Trichothecium sinensesp. nov. (Myrotheciomycetaceae), isolated from a dead scale insect, larva and spider, respectively, were introduced as novel taxa, based on the morphological characteristics and DNA-based phylogenetic analyses. This is the first time that a species from Myrotheciomycetaceae is reported from the karst habitats. In addition, the genus Myrotheciomyces is treated as a synonym of Trichothecium based on the phylogenetic analysis, and the type species of the former is transferred to the latter genus.

Auxin was recognized as a secondary dormancy phytohormone, controlling seed dormancy and germination. However, the exogenous auxin-controlled seed dormancy and germination remain unclear in physiological process and gene network. Tobacco seeds soaked in 1000 mg/l auxin solution showed markedly decreased germination compared with that in low concentration of auxin solutions and ddH2O. Using an electron microscope, observations were made on the seeds which did not unfold properly in comparison to those submerged in ddH2O. The radicle traits measured by WinRHIZO, were found to be also weaker than the other treatment groups. Quantified by ELISA, there was no significant difference found in β-1,3glucanase activity and abscisic acid (ABA) content between the seeds imbibed in gradient concentration of auxin solution and those soaked in ddH2O. However, gibberellic acid (GA) and auxin contents were significantly higher at the time of exogenous auxin imbibition and were gradually reduced at germination. RNA sequencing (RNA-seq), revealed that the transcriptome of auxin-responsive dormancy seeds were more similar to that of the imbibed seeds when compared with primary dormancy seeds by principal component analysis. The results of gene differential expression analysis revealed that auxin-controlled seed secondary dormancy was associated with flavonol biosynthetic process, gibberellin metabolic process, adenylyl-sulfate reductase activity, thioredoxin activity, glutamate synthase (NADH) activity and chromatin regulation. In addition, auxin-responsive germination responded to ABA, auxin, jasmonic acid (JA) and salicylic acid (SA) mediated signaling pathway (red, far red and blue light), glutathione and methionine (Met) metabolism. In this study, exogenous auxin-mediated seed secondary dormancy is an environmental model that prevents seed germination in an unfavorable condition. Seeds of which could not imbibe normally, and radicles of which also could not develop normally and emerge. To complete the germination, seeds of which would stimulate more GA synthesis to antagonize the stimulation of exogenous auxin. Exogenous auxin regulates multi-metabolic networks controlling seed secondary dormancy and germination, of which the most important thing was that we found the auxin-responsive seed secondary dormancy refers to epigenetic regulation and germination to enhance Met pathway. Therefore, this study uncovers a previously unrecognized transcriptional regulatory networks and physiological development process of seed dormancy and germination with superfluous auxin signal activate.