Abstract
This PhD thesis investigates the potential of pruning waste compost (PWC), either non inoculated or inoculated with a consortium of mycorrhizal fungi and Trichoderma, as sustainable alternatives to conventional fertilisation in vineyard management. This study employs a multi-level approach to evaluate the multifaceted impact of PWC and inoculated PWC (iPWC) on soil health, plant nutrition, and grape composition. The findings demonstrate the viability of organic amendments for enhancing vineyard productivity within a circular economy framework. The principal techniques employed included the application of compost treatments to potted grapevine cuttings, the analysis of soil and root nutrients, an assessment of microbial communities, and the profiling of metabolites in grape tissues. The findings demonstrate that PWC-based treatments markedly enhanced soil organic matter (SOM) content, microbial activity, and nutrient turnover, particularly in soils that had been previously disturbed by terracing. The compost amendments fostered microbial shifts that were conducive to the proliferation of beneficial copiotrophic and phosphorus-solubilising species, while simultaneously reducing pathogenic fungal populations. The enhanced soil fertility and biological function contributed to the sustained availability of nutrients throughout the critical grapevine growth stages, supporting regular vegetative development and promising yields. From an agronomic perspective, PWC and iPWC demonstrated the potential to yield comparable results to those achieved by mineral fertilisers, particularly in terms of nutrient cycling efficiency and nutrient uptake. Metabolomic analyses revealed that compost-based treatments influenced grape composition, with iPWC promoting the accumulation of hydroxycinnamic acids and NPK favouring the synthesis of terpenoids, thereby underscoring the distinctive benefits of organic amendments in modulating secondary metabolite production and overall grape quality. This research provides valuable insights into achieving the goals of the European Green Deal, and promotes sustainable agricultural practices through the valorisation of vineyard waste. By transforming pruning residues into a valuable resource, PWC-based strategies offer environmentally friendly alternatives to mineral fertilisers, promoting soil resilience, ecological integrity and agricultural sustainability. While the results highlight the efficacy of PWC and iPWC in promoting soil and plant health, further long-term field research is needed to investigate soil response and plant adaptability under different environmental conditions, and to optimise compost formulations tailored to specific vineyard settings. This work provides a basis for the wider adoption of compost-based fertilisation in viticulture, highlighting its critical role in creating more resilient, ecologically sound and sustainable vineyard ecosystems.