title: Resilience of the natural phyllosphere microbiota of the grapevine to chemical and biological pesticides.
abstract: The phyllosphere is colonized by complex microbial communities, which are adapted to the harsh habitat. Although the role and ecology of nonpathogenic microorganisms of the phyllosphere are only partially understood, leaf microbiota could have a beneficial role in plant growth and health. Pesticides and biocontrol agents are frequently applied to grapevines, but the impact on nontarget microorganisms of the phyllosphere has been marginally considered. In this study, we investigated the effect of a chemical fungicide (penconazole) and a biological control agent (Lysobacter capsici AZ78) on the leaf microbiota of the grapevine at three locations. Amplicons of the 16S rRNA gene and of the internal transcribed spacer were sequenced for bacterial and fungal identification, respectively. Pyrosequencing analysis revealed that the richness and diversity of bacterial and fungal populations were only minimally affected by the chemical and biological treatments tested, and they mainly differed according to grapevine locations. Indigenous microbial communities of the phyllosphere are adapted to environmental and biotic factors in the areas where the grapevines are grown, and they are resilient to the treatments tested. The biocontrol properties of phyllosphere communities against downy mildew differed among grapevine locations and were not affected by treatments, suggesting that biocontrol communities could be improved with agronomic practices to enrich beneficial populations in vineyards.
authors.forename: Michele
authors.initials: M
authors.lastname: Perazzolli
authors.forename: Livio
authors.initials: L
authors.lastname: Antonielli
authors.forename: Michelangelo
authors.initials: M
authors.lastname: Storari
authors.forename: Gerardo
authors.initials: G
authors.lastname: Puopolo
authors.forename: Michael
authors.initials: M
authors.lastname: Pancher
authors.forename: Oscar
authors.initials: O
authors.lastname: Giovannini
authors.forename: Massimo
authors.initials: M
authors.lastname: Pindo
authors.forename: Ilaria
authors.initials: I
authors.lastname: Pertot
mesh_terms: D001419:Bacteria / Q000145:classification / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D017753:Ecosystem; D005658:Fungi / Q000145:classification / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D005659:Fungicides, Industrial / Q000494:pharmacology; D053528:Lysobacter / Q000502:physiology*; D064307:Microbiota / Q000187:drug effects; D018515:Plant Leaves / Q000187:drug effects / Q000382:microbiology*; D027843:Vitis / Q000382:microbiology*
chemical_list: D005659:Fungicides, Industrial