title: Effect of biocontrol agent Pseudomonas fluorescens 2P24 on soil fungal community in cucumber rhizosphere using T-RFLP and DGGE.
abstract: Fungi and fungal community play important roles in the soil ecosystem, and the diversity of fungal community could act as natural antagonists of various plant pathogens. Biological control is a promising method to protect plants as chemical pesticides may cause environment pollution. Pseudomonas fluorescens 2P24 had strong inhibitory on Rastonia solanacearum, Fusarium oxysporum and Rhizoctonia solani, etc., and was isolated from the wheat rhizosphere take-all decline soils in Shandong province, China. However, its potential effect on soil fungal community was still unknown. In this study, the gfp-labeled P. fluorescens 2P24 was inoculated into cucumber rhizosphere, and the survival of 2P24 was monitored weekly. The amount decreased from 10(8) to 10(5) CFU/g dry soils. The effect of 2P24 on soil fungal community in cucumber rhizosphere was investigated using T-RFLP and DGGE. In T-RFLP analysis, principle component analysis showed that the soil fungal community was greatly influenced at first, digested with restriction enzyme Hinf I and Taq I. However, there was little difference as digested by different enzymes. DGGE results demonstrated that the soil fungal community was greatly shocked at the beginning, but it recovered slowly with the decline of P. fluorescens 2P24. Four weeks later, there was little difference between the treatment and control. Generally speaking, the effect of P. fluorescens 2P24 on soil fungal community in cucumber rhizosphere was just transient.
authors.affiliation: State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China.
authors.forename: Guanpeng
authors.initials: G
authors.lastname: Gao
authors.forename: Danhan
authors.initials: D
authors.lastname: Yin
authors.forename: Shengju
authors.initials: S
authors.lastname: Chen
authors.forename: Fei
authors.initials: F
authors.lastname: Xia
authors.forename: Jie
authors.initials: J
authors.lastname: Yang
authors.forename: Qing
authors.initials: Q
authors.lastname: Li
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
mesh_terms: D018553:Cucumis sativus / Q000382:microbiology*; D058645:Denaturing Gradient Gel Electrophoresis; D005658:Fungi; D010572:Pest Control, Biological / Q000379:methods*; D010935:Plant Diseases / Q000517:prevention & control*; D012150:Polymorphism, Restriction Fragment Length; D011551:Pseudomonas fluorescens; D058441:Rhizosphere; D012987:Soil; D012988:Soil Microbiology
chemical_list: D012987:Soil