| Title: | Soil bacterial diffusible and volatile organic compounds inhibit Phytophthora capsici and promote plant growth |
| Author(s): | Syed-Ab-Rahman SF; Carvalhais LC; Chua ET; Chung FY; Moyle PM; Eltanahy EG; Schenk PM; |
| Address: | "Plant-Microbe Interactions Laboratory, School of Agriculture and Food Sciences, The University of Queensland, Brisbane, Queensland 4072, Australia; School of Pharmacy, The University of Queensland, Pharmacy Australia Centre of Excellence (PACE), Woolloongabba, Queensland 4102, Australia. Electronic address: s.syedabrahman@uqconnect.edu.au. Centre for Horticultural Science, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Ecosciences Precinct, GPO Box 267, Queensland 4001, Australia. Plant-Microbe Interactions Laboratory, School of Agriculture and Food Sciences, The University of Queensland, Brisbane, Queensland 4072, Australia. School of Pharmacy, The University of Queensland, Pharmacy Australia Centre of Excellence (PACE), Woolloongabba, Queensland 4102, Australia. Botany Department, Faculty of Science, Mansoura University, Mansoura 35516, Egypt" |
| DOI: | 10.1016/j.scitotenv.2019.07.061 |
| ISSN/ISBN: | 1879-1026 (Electronic) 0048-9697 (Linking) |
| Abstract: | "Biotic interactions through diffusible and volatile organic compounds (VOCs) are frequent in nature. Soil bacteria are well-known producers of a wide range of volatile compounds (both organic and inorganic) with various biologically relevant activities. Since the last decade, they have been identified as natural biocontrol agents. Volatiles are airborne chemicals, which when released by bacteria, can trigger plant responses such as defence and growth promotion. In this study, we tested whether diffusible and volatile organic compounds (VOCs) produced by soil bacterial isolates exert anti-oomycete and plant growth-promoting effects. We also investigated the effects of inoculation with VOC-producing bacteria on the growth and development of Capsicum annuum and Arabidopsis thaliana seedlings. Our results demonstrate that organic VOCs emitted by bacterial antagonists negatively influence mycelial growth of the soil-borne phytopathogenic oomycete Phytophthora capsici by 35% in vitro. The bacteria showed plant growth promoting effects by stimulating biomass production, primary root growth and root hair development. Additionally, we provide evidence to suggest that these activities were deployed by the emission of either diffusible organic compounds or VOCs. Bacterial VOC profiles were obtained through solid phase microextraction (SPME) and analysis by gas chromatography coupled with mass spectrometry (GC-MS). This elucidated the main volatiles emitted by the isolates, which covered a wide range of aldehydes, alcohols, esters, carboxylic acids, and ketones. Collectively, twenty-five VOCs were identified to be produced by three bacteria; some being species-specific. Our data show that bacterial volatiles inhibits P. capsici in vitro and modulate both plant growth promotion and root system development. These results confirm the significance of soil bacteria and highlights that ways of harnessing them to improve plant growth, and as a biocontrol agent for soil-borne oomycetes through their volatile emissions deserve further investigation" |
| Keywords: | Arabidopsis/*drug effects/growth & development Bacteria/*chemistry Capsicum/*drug effects/growth & development Mycelium/drug effects/growth & development Phytophthora/*drug effects/growth & development Seedlings/drug effects/growth & development *Soil Mic; |
| Notes: | "MedlineSyed-Ab-Rahman, Sharifah Farhana Carvalhais, Lilia C Chua, Elvis T Chung, Fong Yi Moyle, Peter M Eltanahy, Eladl G Schenk, Peer M eng Netherlands 2019/07/28 Sci Total Environ. 2019 Nov 20; 692:267-280. doi: 10.1016/j.scitotenv.2019.07.061. Epub 2019 Jul 5" |
