Plant metabolic enhancement
The process of enhancement of plant metabolism refers to an increase of general plant metabolic responses. This process will indirectly help the plants with coping against pathogens and pests rather than directly targeting a specific pathogen or pest. Pathogens and or pests do not necessarily have to be present when this process occurs. Examples of this process are the enhancement of plant nutrition (e.g., N fixation, P solubilisation, Fe chelation), reduction of abiotic stresses, increasing photosynthetic rate, enhancement of constitutive defence against pathogen/pests, production of phytohormones with positive effect on root growth and development (e.g., auxine and gibberellins). Often the plant has a direct role in choosing the organisms that will enhance its health by attracting them through the release of volatiles or exudates.
Enhancement of plant metabolism is considered under the Disease and Pest Management function only. Through the enhancement of plant metabolism, soil organisms are ultimately able to increase plant health and resistance to pathogens and pests, limiting their damages and controlling the damages they might cause to plants.
Enhancement of plant metabolism can be estimated by measuring plant growth promoting activities with in-lab based bioassays[1], or culturing organisms and extract specific compounds involved in plant metabolism enhancement[2]. Other methods rely on molecular quantification of functional genes and transcripts involved in enhancement of plant metabolism with qPCR and RT-PCR, respectively[3],[4].
[1] Abbasi S et al. 2019. Streptomyces Strains Induce Resistance to Fusarium oxysporum f. Sp. Lycopersici Race 3 in Tomato through Different Molecular Mechanisms. Frontiers in Microbiology 10.
[2] Idris AH et al. 2008. Suppression of Pythium ultimum root rot of sorghum by rhizobacterial isolates from Ethiopia and South Africa. Biological Control 45: 72–84.
[3] Imperiali N et al. 2019. Relationships between Root Pathogen Resistance, Abundance and Expression of Pseudomonas Antimicrobial Genes, and Soil Properties in Representative Swiss Agricultural Soils. Frontiers Plant Science 29.
[4] De Coste NJ et al. 2010. Verticillium dahliae alters Pseudomonas spp. populations and HCN gene expression in the rhizosphere of strawberry. Canadian Journal of Microbiology 56: 906-915.