1,721,043 research outputs found
Valorizzazione del compost ottenuto dalla pulitura dei castagneti attraverso la messa a punto di cumuli statici areati
No full textDati preliminari sulla caratterizzazione di un mutante di Sinorhizobium meliloti 1021 Kanamicina resistente e sale sensibile.
No full textBiomass conversion strategies and wastewater reuse: a deep focus on hydrothermal liquefaction as a circular economy approach
No full textA wide variety of eco-friendly and at zero waste techniques are developed for biomass conversion and valorization
of its residues and by-products such as water fraction and organic residues which could be further utilized. The wastewater reuse is one of the best strategies for water security, sustainability, and resilience. To date, the municipal wastewater was the most widely used, nowadays the innovative technologies for biomass conversion and energy production allow the recovery of wastewater with better and safer features than the municipal effluents. Depending on the moisture content of the starting feedstock, the hydrothermal liquefaction process (HTL) generates also up to 95% of wastewater (HTL–WW) generally rich in nitrogen, phosphorus, and sulfate as well as micronutrients and miner- als. Although it is currently recycled through various biological systems such as microalgae cultivation and anaerobic digestion, the possibility of using the wastewater from HTL process as irrigation water for agricultural purpose is dis- cussed representing a source of crop nutrients for the high amount of organic and inorganic compounds and a new approach in contributing to reduce the increasing pressure on freshwater resources
Effectiveness of Plant Beneficial Microbes: Overview of the Methodological Approaches for the Assessment of Root Colonization and Persistence
No full textIssues concerning the use of harmful chemical fertilizers and pesticides that have large negative impacts on environmental and human health have generated increasing interest in the use of beneficial microorganisms for the development of sustainable agri-food systems. A successful microbial inoculant has to colonize the root system, establish a positive interaction and persist in the environment in competition with native microorganisms living in the soil through rhizocompetence traits. Currently, several approaches based on culture-dependent, microscopic and molecular methods have been developed to follow bioinoculants in the soil and plant surface over time. Although culture-dependent methods are commonly used to estimate the persistence of bioinoculants, it is difficult to differentiate inoculated organisms from native populations based on morphological characteristics. Therefore, these methods should be used complementary to culture-independent approaches. Microscopy-based techniques (bright-field, electron and fluorescence microscopy) allow to obtain a picture of microbial colonization outside and inside plant tissues also at high resolution, but it is not possible to always distinguish living cells from dead cells by direct observation as well as distinguish bioinoculants from indigenous microbial populations living in soils. In addition, the development of metagenomic techniques, including the use of DNA probes, PCR-based methods, next-generation sequencing, whole-genome sequencing and pangenome methods, provides a complementary approach useful to understand plant–soil–microbe interactions. However, to ensure good results in microbiological analysis, the first fundamental prerequisite is correct soil sampling and sample preparation for the different methodological approaches that will be assayed. Here, we provide an overview of the advantages and limitations of the currently used methods and new methodological approaches that could be developed to assess the presence, plant colonization and soil persistence of bioinoculants in the rhizosphere. We further discuss the possibility of integrating multidisciplinary approaches to examine the variations in microbial communities after inoculation and to track the inoculated microbial strains
Probiotic activities and root colonization of new Kosakonia pseudosacchari strains isolated from wheat rhizosphere under stress conditions.
No full textIsolamento e caratterizzazione di lieviti autoctoni per la valorizzazione di vini tipici campani.
No full textEffect of agricultural practices on soil microbial communities
No full textSoil carbon sequestration is an important and immediate sink for removing atmospheric carbon dioxide and slowing global warming. Agricultural practices strongly impact CO2 emission from the soil and the loss of soil organic matter is lower when “no-till” agriculture is practiced. The present work was performed in order to investigate effects of different agricultural practices on soil microbial communities.
Field experiments took place at three Italian locations strongly differing in pedological, chemical and climatic characteristics: Naples, Turin and Piacenza. Soils were subjected to four management practices such as traditional (TRA), minimum tillage (MIN) and amendments with compost (COM) known to be responsible in limiting CO2 release from agricultural soils, and synthetic metalporphyrins (POR) addition. Soil and rhizosphere samples from pots under wheat and maize cropping were sampled at different time and the composition of microbial groups directly implicated in OM mineralization, such as actinobacteria, fungi and cellulosolytic bacteria, as well as microbial groups involved in key bio-geochemical processes (e.g. aerobic free-living N2-fixing bacteria and ammonia-oxidizing bacteria) was estimated and culturable populations structure discussed. Moreover, the effect of synthetic metalporphyrins addition on the destiny of microbial populations responsible for important processes in soil biological activity was evaluated.
As expected, different results were obtained depending on the field under study. A Principal Component Analysis (PCA) was applied to the overall set of results obtained from our field experiments to get a general outlook of the major factors influencing microbial distribution. The factors bulk – maize rhizosphere were the principal ones influencing distribution within the samples. In fact, a strong rhizosphere effect was exerted from the maize rhizosphere towards almost all microbial groups. Among the treatments only the compost addition (COM) showed a similar trend.
Moreover, synthetic metalporphyrins amendment did not strongly influence the cultivable bacterial population. In fact, the strongest effect associated to the POR treatment in comparison with the control without porphyrin (NO POR) was related to the relatively higher counts of nitrogen - fixing bacteria found in the POR treatment and a decrease in ammonia-oxidizing bacteria.
Our results emphasize the positive effect exerted by compost addition towards many microbial populations known to be important in the turn-over of OM, such as actinobacteria, fungi and cellulosolytic bacteria. This was particularly true in bulk soil, whereas in maize rhizosphere the different practices did not show such an obvious effect.
This work was supported by FISR-MIUR Italy, (MESCOSAGR Project
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