| Title: | Volatile Compounds of Endophytic Bacillus spp. have Biocontrol Activity Against Sclerotinia sclerotiorum |
| Author(s): | Massawe VC; Hanif A; Farzand A; Mburu DK; Ochola SO; Wu L; Tahir HAS; Gu Q; Wu H; Gao X; |
| Address: | "Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, PR China" |
| DOI: | 10.1094/PHYTO-04-18-0118-R |
| ISSN/ISBN: | 0031-949X (Print) 0031-949X (Linking) |
| Abstract: | "To develop an effective biological agent to control Sclerotinia sclerotiorum, three endophytic Bacillus spp. strains with high antagonistic activity were isolated from maize seed and characterized. In vitro assays revealed that the Bacillus endophytes could produce volatile organic compounds (VOC) that reduced sclerotial production and inhibited mycelial growth of S. sclerotiorum. Gas chromatography-mass spectrometry revealed that the selected strains produced 16 detectable VOC. Eight of the produced VOC exhibited negative effects on S. sclerotiorum, while a further four induced accumulation of reactive oxygen species in mycelial cells. A mixture of VOC produced by Bacillus velezensis VM11 caused morphological changes in the ultrastructure and organelle membranes of S. sclerotiorum mycelial cells. The bromophenol blue assay revealed a yellow color of untreated fungal mycelium, which grew faster and deeper from 24 to 72 h postinoculation, as an indication of reduced pH. The potassium permanganate (KMnO(4)) titration assay showed that the rate of oxalic acid accumulation was higher in minimal salt liquid medium cultures inoculated with untreated fungal plugs compared with the Bacillus VOC-treated ones. Interestingly, biological control assays using host-plant leaves challenged with treated fungal mycelial plugs produced reduced lesions compared with the control. These findings provide new viable possibilities of controlling diseases caused by S. sclerotiorum using VOC produced by Bacillus endophytes" |
| Keywords: | "*Antibiosis Antifungal Agents/metabolism/*pharmacology Ascomycota/*drug effects/growth & development/ultrastructure Bacillus/*chemistry/genetics/physiology Endophytes Solanum lycopersicum/microbiology Microscopy, Electron, Transmission Mycelium/drug effec;" |
| Notes: | "MedlineMassawe, Venance Colman Hanif, Alvina Farzand, Ayaz Mburu, David Kibe Ochola, Sylvans Ochieng Wu, Liming Tahir, Hafiz Abdul Samad Gu, Qin Wu, Huijun Gao, Xuewen eng Research Support, Non-U.S. Gov't 2018/06/22 Phytopathology. 2018 Dec; 108(12):1373-1385. doi: 10.1094/PHYTO-04-18-0118-R. Epub 2018 Oct 31" |
