Abstract

The role of microbial-emitted volatiles also termed ‘infochemicals’ in agriculture is an emerging area of research with many perceived attributes including but not limited to the alleviation of abiotic and biotic stress factors. Several reports in the literature to date have demonstrated the potential of these mVOCs in plant growth-promotion and disease-suppression, albeit mainly under artificial conditions. The mVOCs are low molecular mass compounds with a high vapour pressure and low boiling point and through diffusion can affect a response over a long distance both above and below ground. They belong to many different classes of chemicals that include terpenes, alcohols, alkenes and ketones amongst others. This review examines recent literature in this area and cites examples of mVOCs, or more particularly; bacterial-derived volatile compounds hereby referred to as ‘BVCs’, that have plant growth promoting and biocontrol effects. The multifaceted role of BVCs can be viewed as an integral part of a second green revolution in agriculture where alternative environmentally-friendly solutions are being sought for crop protection and bio-stimulation. Their ability to modulate plant photosynthetic and ISR pathways may provide the agricultural sector with more sustainable solutions for increased crop protection and production in the face of increasing climate and population changes.