Biogenic Volatile Compounds for Plant Disease Diagnosis and Health Improvement

  • Sharifi, Rouhallah (Department of Plant Protection, College of Agriculture and Natural Resources, Razi University) ;
  • Ryu, Choong-Min (Molecular Phytobacteriology Laboratory, Infectious Disease Research Center, KRIBB)
  • Received : 2018.06.30
  • Accepted : 2018.09.12
  • Published : 2018.12.01


Plants and microorganisms (microbes) use information from chemicals such as volatile compounds to understand their environments. Proficiency in sensing and responding to these infochemicals increases an organism's ecological competence and ability to survive in competitive environments, particularly with regard to plant-pathogen interactions. Plants and microbes acquired the ability to sense and respond to biogenic volatiles during their evolutionary history. However, these signals can only be interpreted by humans through the use of state-of the-art technologies. Newly-developed tools allow microbe-induced plant volatiles to be detected in a rapid, precise, and non-invasive manner to diagnose plant diseases. Beside disease diagnosis, volatile compounds may also be valuable in improving crop productivity in sustainable agriculture. Bacterial volatile compounds (BVCs) have potential for use as a novel plant growth stimulant or as improver of fertilizer efficiency. BVCs can also elicit plant innate immunity against insect pests and microbial pathogens. Research is needed to expand our knowledge of BVCs and to produce BVC-based formulations that can be used practically in the field. Formulation possibilities include encapsulation and sol-gel matrices, which can be used in attract and kill formulations, chemigation, and seed priming. Exploitation of biogenic volatiles will facilitate the development of smart integrated plant management systems for disease control and productivity improvement.

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Fig. 1. Non-invasive diagnosis of microbial pathogenic infection and diseased plant tissues by volatile analysis. Volatile interpretation can be separated into two phases: 1. Volatile collection and 2. Volatile analysis. Analysis techniques include quantification of relative amounts of different volatiles and real-time analysis to assess ongoing changes. Volatile collection tools include dynamic sampling methods such as closed-loop-stripping-analysis (CLSA) and static headspace sampling methods such as solid phase microextraction (SPME), stir bar sorptive extraction (SBSE), and silicone tubing (ST). Quantification methods involve conventional gas chromatography-mass spectrometry (GC-MS) and portable GC-MS devices. Real-time analysis tools include Proton Transfer Reaction (PTR)-MS, multi-capillary column (MCC)-PTR-MS and E-nose. Two of these technologies, E-nose and portable GCMS, can be used in the field.

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Fig. 2. Preparation of biogenic volatile compound formulations. There are three main steps in the preparation of volatiles for application to crop plants: 1. Emulsification, where an emulsion of volatiles, a polymer such as alginate, gelatin, or starch, and an emulsifier is prepared; 2. Processing, where volatiles are coated with polymers by means of spray drying with heat, coacervation with dissolving compounds such as ethanol, or extrusion with cross-linking compounds such as CaCl2; and 3. Microcapsulation, where microcapsules are separated and dried for field applications.

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Fig. 3. Uses of biogenic volatiles in plant health applications. Microcapsule and sol-gel formulations of biogenic volatile compounds can be used in a range of situations: 1. Storage application; 2. Greenhouse application; 3. Insect pest control; 4. Open-field application; and 5. Seed priming.


Supported by : Ministry of Agriculture, Food and Rural Affairs, Ministry of Science and ICT


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