Guo Yingqiu, Tian Li, Zhu Xinyu, Liu Shu, Wang Lili, Li Wankui
Shanghai University of Traditional Chinese Medicine, Shanghai, China.
Shanghai Pudong Zhangjiang Innovation Research Institute of Traditional Chinese Medicine, Shanghai, China.
Microb Ecol. 2025 May 8;88(1):40. doi: 10.1007/s00248-025-02539-8.
Saffron can be infected with pathogenic fungi that cause corm rot as it grows and multiplies, which can reduce the quality and yield of saffron. Corm rot has become one of the most serious diseases of saffron. In this study, rhizosphere bacteria were isolated from saffron rhizosphere soil, and bacteria exhibiting antagonistic effects against corm rot pathogenic fungi were screened using in vitro plate co-culture assays and dual-compartment agar plate systems. Selected strains were further evaluated for hydrolase activity determination and PGP potential assessment. Among them, Bacillus velezensis showed the best disease resistance activity. The degradative enzyme production and some beneficial characteristics of Bacillus velezensis for plant growth promotion were evaluated. It was found that Bacillus velezensis possesses nitrogen fixing, NH-producing, IAA production, and ACC-deaminating enzymes. The whole genome sequence of this strain was annotated and analyzed. The genome of Bacillus velezensis consists of a circular chromosome of 3,908,025 bp base pairs, with a guanine and cytosine content of 46.64%. There are 3737 protein-coding genes, including 86 tRNA genes, 27 rRNA genes, and 85 sRNA genes. The genome also contains four genomic islands, two pre-phages, and one transposon. The prediction of the secondary metabolic accumulation gene cluster demonstrated that the genome sequence of ZGE166 encodes 12 gene clusters involved in the synthesis of secondary metabolites, including macrolactin H, bacillaene, fengycin, difficidin, and bacillibactin. In summary, strain ZGE166 Bacillus velezensis has the potential to be developed as a biological agent.
藏红花在生长和繁殖过程中会受到导致球茎腐烂的致病真菌感染，这会降低藏红花的品质和产量。球茎腐烂已成为藏红花最严重的病害之一。在本研究中，从藏红花根际土壤中分离出根际细菌，并使用体外平板共培养试验和双室琼脂平板系统筛选对球茎腐烂致病真菌具有拮抗作用的细菌。对筛选出的菌株进一步进行水解酶活性测定和植物促生潜力评估。其中，贝莱斯芽孢杆菌表现出最佳的抗病活性。对贝莱斯芽孢杆菌的降解酶产生及一些促进植物生长的有益特性进行了评估。发现贝莱斯芽孢杆菌具有固氮、产氨、产吲哚-3-乙酸和1-氨基环丙烷-1-羧酸脱氨酶。对该菌株的全基因组序列进行了注释和分析。贝莱斯芽孢杆菌的基因组由一条3,908,025碱基对的环状染色体组成，鸟嘌呤和胞嘧啶含量为46.64%。有3737个蛋白质编码基因，包括86个tRNA基因、27个rRNA基因和85个sRNA基因。基因组还包含四个基因组岛、两个前噬菌体和一个转座子。次生代谢产物积累基因簇的预测表明，ZGE166的基因组序列编码12个参与次生代谢产物合成的基因簇，包括大环内酯H、杆菌烯、丰原素、艰难梭菌素和杆菌铁载体。总之，ZGE166贝莱斯芽孢杆菌菌株有潜力被开发为一种生物制剂。
