Guangying Liu1,2, Xu Lin1,2, Shuangyu Xu1,2, Guang Liu1,2, Feng Liu1,2, Wei Mu1,2. 1. Key Laboratory of Pesticide Toxicology and Application Technique, College of Plant Protection Shandong Agricultural University, Tai'an, PR China. 2. College of Plant Protection, Shandong Agricultural University, Tai'an, PR China.
Abstract
BACKGROUND: Root-knot nematodes (Meloidogyne spp.) are soilborne pathogens that can cause great damage to and economic loss of crops globally. Owing to the high toxicity of chemicals toward humans and the environment, the use of biocontrol bacteria, a promising method for controlling root-knot nematodes, has gained attention. RESULTS: To screen novel bacterial strains for their ability to control root-knot nematodes, 106 bacterial strains were isolated from soil. Eight of the obtained isolates exhibited satisfactory nematicidal activity against Meloidogyne incognita at 2-fold dilutions (approximately 3 × 1012 CFU mL-1 ) after 12 h of exposure. Based on their physiological, biochemical and molecular (16S rRNA and gyrB gene sequences) characteristics, the eight strains were identified as Bacillus halotolerans, B. kochii, B. oceanisediminis, B. pumilus, B. toyonensis, B. cereus, Pseudomonas aeruginosa and B. pseudomycoides. In greenhouse and field experiments, the eight isolates suppressed M. incognita up to 69.96% compared to the control. Additionally, the yield of tomato increased 1.4-26.1% over that of the control. CONCLUSION: The strains of B. halotolerans DDWA, B. kochii DDWB, B. oceanisediminis DDWC and B. pseudomycoides JNC have potential to control M. incognita, which has not been previously reported.
BACKGROUND:Root-knot nematodes (Meloidogyne spp.) are soilborne pathogens that can cause great damage to and economic loss of crops globally. Owing to the high toxicity of chemicals toward humans and the environment, the use of biocontrol bacteria, a promising method for controlling root-knot nematodes, has gained attention. RESULTS: To screen novel bacterial strains for their ability to control root-knot nematodes, 106 bacterial strains were isolated from soil. Eight of the obtained isolates exhibited satisfactory nematicidal activity against Meloidogyne incognita at 2-fold dilutions (approximately 3 × 1012 CFU mL-1 ) after 12 h of exposure. Based on their physiological, biochemical and molecular (16S rRNA and gyrB gene sequences) characteristics, the eight strains were identified as Bacillus halotolerans, B. kochii, B. oceanisediminis, B. pumilus, B. toyonensis, B. cereus, Pseudomonas aeruginosa and B. pseudomycoides. In greenhouse and field experiments, the eight isolates suppressed M. incognita up to 69.96% compared to the control. Additionally, the yield of tomato increased 1.4-26.1% over that of the control. CONCLUSION: The strains of B. halotolerans DDWA, B. kochii DDWB, B. oceanisediminis DDWC and B. pseudomycoides JNC have potential to control M. incognita, which has not been previously reported.
Authors: Renjun Zhang; Jin Ouyang; Xingyang Xu; Jie Li; Muzammal Rehman; Gang Deng; Jie Shu; Dake Zhao; Suiyun Chen; R Z Sayyed; Shah Fahad; Yaqiong Chen Journal: Front Microbiol Date: 2022-06-10 Impact factor: 6.064