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Selci, M.

Publications and source records attributed to Selci, M..

2 recordsLinked to original sources

Bacterioplankton Diversity and Distribution in Relation to Phytoplankton Community Structure in the Ross Sea surface waters

Primary productivity in the Ross Sea region is characterized by intense phytoplankton blooms whose temporal and spatial distribution are driven by changes in environmental conditions as well as interactions with the bacterioplankton community. Exchange of exudates, metabolism by-products and cofactors between the phytoplankton and the bacterioplankton communities drive a series of complex interactions affecting the micronutrient availability and co-limitation, as well as nutrient uptakes in Antarctic waters. Yet, the number of studies reporting the simultaneous diversity of the phytoplankton and bacterioplankton in Antarctic waters are limited. Here we report data on the bacterial diversity in relation to phytoplankton community in the surface waters of the Ross Sea during the austral summer 2017. Our results show partially overlapping bacterioplankton communities between the stations located in the Terra Nova Bay coastal waters and the Ross Sea open waters, suggesting that the two communities are subjected to different drivers. We show that the rate of diversity change between the two locations is influenced by both abiotic (salinity and the nitrogen to phosphorus ratio) and biotic (phytoplankton community structure) factors. Our data provides new insight into the coexistence of the bacterioplankton and phytoplankton in Antarctic waters.

microbiology↗

Genomic Mining and Physiological Characterization of new Halophilic Plant Growth Promoting Bacilli

Massive application of chemical fertilizers and pesticides has been the main strategy used to cope with the rising crop demands in the last decades. The indiscriminate use of chemicals while providing a temporary solution to food demand has led to a decrease in crop productivity and an increase in the environmental impact of modern agriculture. A sustainable alternative to the use of chemicals for crop production is the use of microorganisms naturally capable of enhancing plant growth and protecting crops from pests, known as Plant-Growth-Promoting Bacteria (PGPB). Aim of the present study was to isolate and characterize PGPB from salt-pans sand samples able to ameliorate plant fitness. To survive high salinity, salt-tolerant microbes produce a broad range of compounds with heterogeneous biological activities that are potentially beneficial for plant growth. We have isolated and screened in vitro a total of 20 halophilic spore-forming bacteria for phyto-beneficial traits and compared the results with two Bacilli recently isolated from the rhizosphere of the same collection site and recently characterized as potential biocontrol agents. Whole-genome analysis on five selected halophilic strains confirmed the presence of numerous gene clusters with PGP and biocontrol functions and of novel secondary-metabolite biosynthetic genes potentially involved in plant growth promotion and protection. The predicted biocontrol potential was confirmed in dual culture assays against several phytopathogenic fungi and bacteria. Interestingly, the absence of predicted gene clusters with known biocontrol functions in some of the isolates was not predictive of the in vitro results, supporting the need of combining laboratory assays and genome mining in PGPB identification for future applications.

microbiology↗