4株生防细菌对燕麦根腐病原菌抑菌特性研究

Inhibition characteristics of four strains of biocon⁃trol bacteria against root rot pathogens of oats

摘要:

【目的】 探究3 株芽孢杆菌LSH11、R1、TZF‐1 和1 株类芽孢杆菌CCM 对燕麦根腐病病原菌的抑制效果及其抑菌特性。【方法】 以燕麦根腐病病原菌麦根腐平脐孺孢菌（Bipolaris sorokiniana）和串珠赤霉菌（Gibberella moniliformis）为靶标菌，利用十字交叉法测定4 株生防细菌的抑菌能力；采用透明圈法测定菌株产蛋白酶、纤维素酶及其淀粉酶的能力；采用结晶紫染色检测菌株形成生物膜的能力，利用分子生物学方法检测菌株是否具有合成相关脂肽类物质的基因。【结果】 4 株生防细菌对两种病原菌均具有较好的抑制效果，抑制率达53% 以上，并导致真菌菌丝出现异常断裂、分枝、畸形、内含物质外泄的现象。4 株菌均具备产蛋白酶、淀粉酶和纤维素酶的能力，并且均具有形成生物膜的能力。扩增脂肽物质相关基因（ituA 、ituB 、ituC 、ituD 、fenA、fenD、srfAA ）发现3 株芽孢杆菌均具有脂肽类物质合成的相关基因。【结论】 4 株生防细菌可分泌水解酶等抑菌类物质，具有良好的应用潜力，其中菌株R1和TZF-1 综合生防特性较好，可用于后期生防菌肥的制作和燕麦根腐病的生物防治。

Abstract:

【Objective】 This research aimed to investigate the inhibitory effect and characteristics of three strainsof Bacillus LSH11，R1，TZF ‐1 and one strain of Bacillus cereus CCM on the root rot pathogen of oats.【Method】The oat root rot pathogens （Bipolaris sorokiniana and Gibberella moniliformis） were selected as target bacteria todetermine the bacterial inhibitory capacity of four strains of biocontrol bacteria using the crossover method. The abilityof the strains to produce protease，cellulase and its amylase was assessed using the clear circle method. The abilityof the strains to form biofilm was detected using crystalline violet staining，and molecular biological methods were em ‐ployed to ascertain whether the strains possessed genes for the synthesis of related lipopeptide substances.【Result】The results showed that allfour strains of biocontrol bacteria exhibited a significant inhibitory effect on both pathogens，with an inhibition rate of 53%. This inhibition led to abnormal fracture of fungal mycelium，manifested asbranching，deformation，and leakage of inner material. All four strains demonstrated the ability to produce protease，amylase and cellulase，and they all exhibited biofilm ‐forming capabilities. Amplification of lipopeptide ‐related genes（ituA，ituB，ituC，ituD，fenA，fenD，srfAA） revealed that all three Bacillus strains possessed genes related to the synthesisof lipopeptides.【Conclusion】 The four strains of antibacterial bacteria demonstrated the secretion of antibacterialsubstances such as hydrolytic enzymes，which have great potential for application. Notably，strains R1 and TZF‐1exhibited superior integrated biocontrol characteristics，making them suitable for the production of late stage biocontrolfertilizer and biological control of oat root rot.