| Title: | Volatile Molecules Secreted by the Wheat Pathogen Parastagonospora nodorum Are Involved in Development and Phytotoxicity |
| Author(s): | Muria-Gonzalez MJ; Yeng Y; Breen S; Mead O; Wang C; Chooi YH; Barrow RA; Solomon PS; |
| Address: | "Research School of Biology, ACT, Australian National University, Canberra, ACT, Australia. Department of Oral Biology and Biomedical Sciences, MAHSA University, Selangor, Malaysia. School of Molecular Sciences, University of Western Australia, Perth, WA, Australia. Graham Centre for Agricultural Innovation, Charles Sturt University, Wagga Wagga, NSW, Australia. Plus 3 Australia Pty Ltd., Hawker, ACT, Australia" |
| ISSN/ISBN: | 1664-302X (Print) 1664-302X (Electronic) 1664-302X (Linking) |
| Abstract: | "Septoria nodorum blotch is a major disease of wheat caused by the fungus Parastagonospora nodorum. Recent studies have demonstrated that secondary metabolites, including polyketides and non-ribosomal peptides, produced by the pathogen play important roles in disease and development. However, there is currently no knowledge on the composition or biological activity of the volatile organic compounds (VOCs) secreted by P. nodorum. To address this, we undertook a series of growth and phytotoxicity assays and demonstrated that P. nodorum VOCs inhibited bacterial growth, were phytotoxic and suppressed self-growth. Mass spectrometry analysis revealed that 3-methyl-1-butanol, 2-methyl-1-butanol, 2-methyl-1-propanol, and 2-phenylethanol were dominant in the VOC mixture and phenotypic assays using these short chain alcohols confirmed that they were phytotoxic. Further analysis of the VOCs also identified the presence of multiple sesquiterpenes of which four were identified via mass spectrometry and nuclear magnetic resonance as beta-elemene, alpha-cyperone, eudesma-4,11-diene and acora-4,9-diene. Subsequent reverse genetics studies were able to link these molecules to corresponding sesquiterpene synthases in the P. nodorum genome. However, despite extensive testing, these molecules were not involved in either of the growth inhibition or phytotoxicity phenotypes previously observed. Plant assays using mutants of the pathogen lacking the synthetic genes revealed that the identified sesquiterpenes were not required for disease formation on wheat leaves. Collectively, these data have significantly extended our knowledge of the VOCs in fungi and provided the basis for further dissecting the roles of sesquiterpenes in plant disease" |
| Keywords: | Parastagonosopora nodorum disease sesquiterpenes volatiles wheat pathogens; |
| Notes: | "PubMed-not-MEDLINEMuria-Gonzalez, Mariano Jordi Yeng, Yeannie Breen, Susan Mead, Oliver Wang, Chen Chooi, Yi-Heng Barrow, Russell A Solomon, Peter S eng Switzerland 2020/04/10 Front Microbiol. 2020 Mar 25; 11:466. doi: 10.3389/fmicb.2020.00466. eCollection 2020" |
