School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang 621010, China.
J Appl Microbiol. 2023 Aug 1;134(8). doi: 10.1093/jambio/lxad185.
This study evaluated the phylogenetic diversity, plant growth promotion capacity, antifungal activity, and biocontrol potential of culturable actinobacterial endophytes isolated from the medicinal plant Aconitum carmichaelii Debeaux.
Isolation of actinobacteria from healthy A. carmichaelii plants was carried out on six different media. Full-length 16S rRNA gene was amplified by PCR from the genomic DNA of each strain. Indole-3-acetic acid and siderophore production were quantitatively assessed by the Salkowski and Chrome Azurol S methods, respectively. Rice seeds germination and seedling growth were employed to evaluate plant growth promotion capacities of candidate strains. Dual-culture assay and pot experiments were performed to investigate the antifungal and biocontrol potential of isolates. We obtained 129 actinobacterial isolates from A. carmichaelii, and they belonged to 49 species in 7 genera. These strains exhibited diverse plant growth promotion ability, among which one strain significantly enhanced rice seeds germination, while 31 strains significantly facilitated rice seedling growth. SWUST-123 showed strong antifungal activity against four pathogens in vitro and was most compatible with Qingchuan cultivar. SWUST-123 reduced around 40% of southern blight disease occurrence compared to blank control treatment. .
Aconitum carmichaelii harbored genetically diverse actinobacterial endophytes exhibiting diverse plant growth promotion and antifungal potential, some of which can be served as good candidates for biofertilizers and biocontrol agents.
本研究评估了从药用植物乌头（Aconitum carmichaelii Debeaux）中分离出的可培养放线菌内生菌的系统发育多样性、植物促生能力、抗真菌活性和生防潜力。
在六种不同的培养基上从健康的乌头植株中分离放线菌。从每个菌株的基因组 DNA 中通过 PCR 扩增全长 16S rRNA 基因。通过 Salkowski 和 Chrome Azurol S 方法定量评估吲哚-3-乙酸和铁载体的产生。采用水稻种子萌发和幼苗生长试验评估候选菌株的植物促生能力。采用双培养试验和盆栽试验研究分离物的抗真菌和生防潜力。从乌头中获得 129 株放线菌，它们属于 7 个属的 49 个种。这些菌株表现出不同的植物促生能力，其中一株显著促进了水稻种子的萌发，而 31 株显著促进了水稻幼苗的生长。SWUST-123 对四种病原菌具有较强的体外抗真菌活性，与庆川品种最相容。与空白对照处理相比，SWUST-123 使南方枯萎病的发生率降低了约 40%。
乌头中蕴藏着具有遗传多样性的放线菌内生菌，具有不同的植物促生和抗真菌潜力，其中一些可以作为生物肥料和生防剂的良好候选物。
