Samsoniella is a very important fungal resource, with some species in the genus having great medical, economic and ecological value. This study reports five new species of Samsoniella from Yunnan Province and Guizhou Province in Southwestern China and Dole Province in Vietnam, providing morphological descriptions, illustrations, phylogenetic placements, associated hosts and comparisons with allied taxa. Based on morphological observations and phylogenetic analyses of combined nrSSU, nrLSU, tef-1α, rpb1 and rpb2 sequence data, it was determined that these five new species were located in the clade of Samsoniella and different from other species of Samsoniella. The five novel species had morphologies similar to those of other species in the genus, with bright orange cylindrical to clavate stromata (gregarious). The fertile part lateral sides usually had a longitudinal ditch without producing perithecia, and superficial perithecia. The phialides had a swollen basal portion, tapering abruptly into a narrow neck and oval or fusiform one-celled conidia, often in chains. The morphological characteristics of 23 species in Samsoniella, including five novel species and 18 known taxa, were also compared in the present study.

The Cordyceps militaris complex, which is a special group in the genus Cordyceps, is rich in species diversity and is widely distributed in nature. Throughout the investigations of arthropod-pathogenic fungi in the national reserves and in Vietnam parks, collections of C. militaris attacking lepidopteran pupae or larvae were located in the soil and on the leaf litter. The phylogenetic analyses of the combined nrSSU, nrLSU, TEF, RPB1, and RPB2 sequence data indicated that the fungal materials collected in Vietnam belonged to C. militaris and two hidden species in the C. militaris complex. The phylogenetic analyses and morphological comparisons presented here strongly supported the descriptions of C. polystromata and C. sapaensis as new taxa as well as C. militaris as a known species. The morphological characteristics of 11 species in the C. militaris complex, which included two novel species and nine known taxa, were also compared.

Gibellula (Cordycipitaceae, Hypocreales) represents a group of highly specialized obligate fungal pathogens restricted to spider hosts. Species delimitation was conducted using morphological characteristics in combination with multilocus phylogenetic analyses (nrSSU, ITS, nrLSU, tef1-α, rpb1, rpb2), and we recognized nine spider-associated Gibellula species from specimens collected in the Lancang–Mekong biodiversity hotspot (China, Laos, Thailand, and Vietnam). Among them, four are described as new to science: Gibellula longiconidiophora sp. nov., G. mekongensis sp. nov., G. ovorum sp. nov., and G. pseudopilosa sp. nov. The other five species represent new national distributional records: G. yunnanensis (new to Laos), G. pseudopigmentosa (new to Thailand), G. trimorpha (new to Vietnam), G. penicillioides (new to Laos), and G. scorpioides (new to China and Laos). Phylogenetic analyses resolved these taxa into well-supported lineages. Notably, G. ovorum is a rare example of a Gibellula species parasitizing spider egg sacs rather than adult spiders, revealing an unusual substrate shift. Morphological distinctions among the new species include differences in conidiophore length, synnematal development, conidial size, and sporulation patterns. Detailed descriptions, illustrations, and taxonomic comparisons are provided. This study significantly expands the known diversity and geographic distribution of Gibellula in the Lancang–Mekong region and underscores the importance of integrative taxonomy for uncovering hidden diversity in spider-pathogenic fungi.

Poly gamma glutamic acid (PGA) là một polymer có khả năng phân hủy sinh học, hòa tan trong nước và không gây độc, đơn phân gồm D và L – glutamic. PGA được tổng hợp chủ yếu từ Bacillus, được ứng dụng trong nhiều lĩnh vực như thực phẩm, y học, chất dẻo, đặc biệt là nông nghiệp. Nghiên cứu này nhằm mục đích phân lập, tuyển chọn chủng vi khuẩn có khả năng sinh tổng hợp Poly gamma glutamic acid. Từ 30 mẫu đất canh tác rau màu thu thập tại tỉnh Thái Bình, sau khi gia nhiệt (80oC, thời gian 40 phút), đã phân lập được 14 chủng vi khuẩn trong đó 9 chủng được xác định sơ bộ thuộc chi Bacillus theo khoá phân loại của Bergey (1957) và kí hiệu từ TB1 đến TB9. Kết quả nghiên cứu cho thấy 9 chủng này đều có khả năng sinh PGA bằng phương pháp đo quang phổ hấp thu. Trong đó sàng lọc được chủng TB2 có khả năng tổng hợp PGA cao nhất đạt 17,43 (mg/ml). Chủng TB2 được định danh bằng trình tự gen 16S RNA có sự tương đồng 97,73% với chủng Bacillus velezensis AY603658, 97,30% với chủng Bacillus siamensis AJVF01000043 và 97,15% với Bacillus subtilis ABQL01000001.