Abstract: Plant associated microbial communities play key roles in biotic and abiotic stress tolerance as well as nutrient acquisition. The rhizosphere (the nearest soil area to the roots) hosts a rich microbial plant community which provides a pivotal series of beneficial outcomes related to plant growth. Plant roots recruit their rhizosphere microbiome from bulk soil and a small number of the microbes from the rhizosphere enter the plant colonising the root endosphere and some then move to other plant organs. The phylogenetic conservation of rhizosphere microbiomes infers an organized assembly of microbiomes which is directed by mechanisms which are at large unknown. These most likely involve cell-cell interactions amongst microbes, plant-microbe signalling and root exudate effects. Microbial cell-cell communication is a way to dynamically regulate a variety of metabolic and physiological activities in response to the host, environment and microbial neighbors. Plant microbiomes contain a very large number of diverse bacterially produced molecules such as quorum sensing signals, volatiles and secondary metabolites which can play cell-cell signaling roles amongst members of the microbiome. Our present understanding of the numerous different signal molecules which are produced in a microbial community, on how the many different bacteria signal each other and what functions are regulated, is very much in its infancy. Understanding the chemical languages shape the plant microbiome will be very informative on how these communities contribute to plant health and physiology. And will also lead to the development of prebiotic compounds as well as microbial probiotic competence for a more sustainable agriculture of economically important crops.

Bio: Vittorio Venturi (graduated from Edinburgh University, UK in 1988, and received his Ph.D. degree in Microbiology from the University of Utrecht, The Netherlands in 1994. During his PhD research he focused in the regulation of iron-transport processes of beneficial plant associated bacteria which promote plant growth; the monopolization of iron nearby plant roots is an important trait which keeps microbial pathogens away. He then moved as a postdoctoral fellow to the International Centre for Genetic Engineering & Biotechnology (ICGEB), Trieste, Italy, where he started investigating intercellular signaling among bacteria. He then went on to become Group Leader at ICGEB in 1998 continuing his studies on intercellular signaling. He is now particularly interested in (i) how plant associated bacteria undergo interspecies communication and interkingdom signaling with plants and (ii) plant microbiomes and the development of microbial products for a more sustainable agriculture. Since October 2019 he is also acting as the Scientific Coordinator of ICGEB. He has published over 150 articles in peer-reviewed international journals, supervised 17 PhD students and over 10 postdocs.