A Burkholderia cepacia population naturally occurring in the rhizosphere of Zea mays was evaluated by metabolic and molecular profiling and for some traits associated with biocontrol and plant growth promoting (PGP) activity. The purpose was to investigate the potential of this bacterial species closely associated with maize to act as a PGP inoculant. The bacterial strains, isolated on semiselective PCAT medium, were assigned to the species B. cepacia by an analysis of the restriction patterns produced by amplified DNA encoding 16S rRNA (16S rDNA) (ARDRA) with the enzyme AluI. Biodiversity among the 14 B. cepacia isolates was analyzed by the Biolog GN system and by the random amplified polymorphic DNA (RAPD) technique with two 10‐mer primers. The analysis of the Biolog data revealed that all rhizosphere B. cepacia strains formed a tight phenetic cluster which includes B. cepacia LMG 11351, a reference strain isolated from the maize rhizosphere, and allowed us to distinguish single isolates from one another. The analysis of RAPD patterns allowed us to identify two principal groups in this bacterial population. Other tests included in vitro inhibition of the maize pathogens Fusarium spp., analysis of siderophore production, bioassay using maize seeds coated with B. cepacia in soil artificially infested with the maize pathogens Fusarium spp., and greenhouse‐based plant growth promotion experiments with maize. The data obtained demonstrated that all B. cepacia strains displayed a wide antibiosis against the phytopathogenic fungi studied and produced, under low iron conditions, hydroxamate‐like and thiazo‐like siderophores. Moreover, the bioassay allowed us to select six and eight B. cepacia strains with a potential for the biological control of F. proliferatum ITEM‐381 and F. moniliforme ITEM‐504, respectively. Growth promotion experiments showed that the effect of seed bacterization with B. cepacia isolates on maize growth depended on the potting medium used. When a sand‐peat/manure mixture was used, almost all B. cepacia isolates promoted maize growth; whereas, when the soil collected from the field of bacterial isolations was used, only four strains exerted a positive effect on maize growth.

Aquatic ecosystems represent one of the largest reservoirs of phytoplankton accounting for most of the primary production of the Earth. The Lake Massaciuccoli located in Tuscany (Italy) is one of the largest swamps that in ancient times entirely covered the Versilia coastal plain. Despite its peculiar features, especially the eutrophic characteristics, its native microalgal consortia have never been explored up to now. In this work, we isolated and described four autochthonous microalgal strains from different sites in the lake (FB, Idr, CL_Sc, and CL_Ch); the four microalgal strains were identified within the Chlorella sorokiniana clade. We exposed them to ten of the most common or emerging environmental contaminants in order to describe their preliminary response to the tested substances: five metals (As, Fe, Ni, Cu, and Zn), two herbicides (Metolachlor and Sethoxydim), two antibiotics (Ciprofloxacin and Benzylpenicillin) and a non-steroidal anti-inflammatory drug (Ibuprofen). Physiological response of the strains highlighted intraspecific differences; strain CL_Sc was the most tolerant in presence of metals while strain Idr was the most sensitive. All strains were sensitive to sethoxydim and tolerant to metolachlor at all the tested concentrations. Strains FB and Idr were the most sensitive in presence of Ibuprofen while strain CL_Ch was the most sensitive to the highest Benzylpenicillin concentration. Resistance pattern of strain Idr somehow reflects both the phylogenetic and the geographic “isolation” from all other three strains. Finally, optical microscope observation confirmed some differences also in the microalgae morphological aspect. Overall, all the strains showed interesting responses in presence of high concentrations of the tested substances, representing putative interesting candidates for water remediation in wastewater treatment plants.

Fusarium head blight (FHB) is a major fungal disease that causes severe yield and quality loss in wheat. Biological control can be integrated with other management strategies to control FHB. For this purpose, Trichoderma gamsii strain T6085 is a potential biocontrol agent to limit the infection of F. graminearum and F. culmorum in wheat. However, the possible impacts of T. gamsii T6085 on the broader microbiome associated with the wheat plant are not currently understood. Therefore, we identified bacteria and fungi associated with different wheat tissues, including assessment of their relative abundances and dynamics in response to the application of T6085 and over time, using amplicon sequencing. Residues of the prior year’s wheat crop and the current year’s wheat spikes were collected at multiple time points, and kernel samples were collected at harvest. DNA was extracted from the collected wheat tissues, and amplicon sequencing was performed to profile microbiomes using 16S v4 rRNA amplicons for bacteria and ITS2 amplicons for fungi. Quantitative PCR was performed to evaluate the absolute abundances of F. graminearum and T. gamsii in different wheat tissues. Disease progression was tracked visually during the growing season, revealing that FHB severity and incidence were significantly reduced when T6085 was applied to wheat spikes at anthesis. However, treatment with T6085 did not lessen the F. graminearum abundance in wheat spikes or kernels. There were substantial changes in F. graminearum abundance over time; in crop residue, pathogen abundance was highest at the initial time point and declined over time, while in wheat spikes, pathogen abundance increased significantly over time. The predominant bacterial taxa in wheat spikes and kernels were Pseudomonas, Enterobacter, and Pantoea, while Alternaria and Fusarium were the dominant fungal groups. Although the microbiome structure changed substantially over time, there were no community-scale rearrangements due to the T6085 treatment. The work suggests several other taxa that could be explored as potential biocontrol agents to integrate with T6085 treatment. However, the timing and the type of T6085 application need to be improved to give more advantages for T6085 to colonize and reduce the F. graminearum inoculum in the field.

Verticillium species are known as plant pathogens responsible for wilt diseases in a large variety of dicotyledon plants and crops in many parts of the world. Here we present the draft genome sequence of Verticillium dahliae Kleb. (strain VdGL16) isolated in Italy from the invasive alien species Ailanthus altissima (Mill.; commonly known as tree-of-heaven) showing Verticillium wilt symptoms. The comparison between the newly sequenced genome with those publicly available revealed candidate genes putatively involved in pathogenicity. The genome represents a new useful source for future research on Verticillium genetics and biology as well as research on novel approaches in the control of A. altissima.