Abstract
This PhD thesis investigates grapevine resilience under multiple abiotic and biotic stresses, integrating physiological, ionomic, and microbiome approaches to elucidate how rootstock and scion genotypes interact to sustain plant performance under adverse conditions. The research redefines stress tolerance as a holobiont-driven process, where plant genetics, nutrient homeostasis, and rhizosphere microbial communities jointly determine the capacity for adaptation and recovery. Across a series of controlled experiments, the responses of resistant cultivars and rootstocks were evaluated under drought, copper toxicity, and pathogen infection. The findings revealed that genotype identity strongly influenced the coordination between plant physiology and soil–microbe interactions. In particular, resilient genotypes maintained higher photosynthetic efficiency, water status, and ionomic balance, especially for key elements such as potassium, phosphorus, and manganese. These physiological traits were associated with distinct and functionally stable rhizosphere microbiomes enriched in stress-adaptive and nutrient-cycling taxa. The combined analysis of plant and microbial responses demonstrated that the capacity to preserve nutrient stability and microbial functionality under simultaneous stresses represents a fundamental component of grapevine resilience. Moreover, resistant cultivars displayed enhanced physiological recovery and reduced oxidative damage under multifactorial conditions, underscoring the synergistic role of genetic resistance and beneficial microbial associations. This research provides a holistic understanding of grapevine adaptation within the framework of sustainable viticulture. By linking physiological and ionomic regulation with microbial dynamics, it highlights the potential of genotype selection and microbiome management to improve vineyard performance under climate change. The outcomes contribute to the development of resilient, low input viticultural systems that align with the principles of ecological sustainability and resource efficiency.