Silicon in agroecological agroforestry fruit woody systems

Silicon (Si) plays a crucial role in enhancing plant resilience and productive capacity. The thesis integrates literature and experimental research to advance our understanding of Si dynamics from soil-plant systems, particularly within Mediterranean agroecosystems. Chapter 1 reviews current research on Si, identifying critical gaps in Si acquisition and accumulation in fruit and woody species. Innovative agroecological (AE) and agroforestry (AF) models are proposed to bolster ecosystem resilience. Chapter 2 employs interdisciplinary methodologies to characterize soil Si pools and their spatial distribution within the soil matrix, revealing how practices and environment influence Si availability, guiding future precision agriculture and sustainable soil management efforts. Chapter 3 focuses on the economically and culturally significant grapevine (Vitis vinifera) in the Mediterranean. By examining Si concentrations and leaf distribution in the cv. Gaglioppo grafted onto various rootstocks, the study reveals genotype-dependent Si accumulation with rootstocks 17-37 Mgt, and 140 R, demonstrating higher Si concentrations compared to K5BB under hydroponic +Si conditions. Advanced microscopy highlights Si deposition and leaf structures. Insight suggests that rootstocks can improve tolerance to abiotic and biotic stresses and enhance overall viticultural performance. Chapter 4 explores Si nutrition within agroforestry systems by intercropping grapevines with Fraxinus ornus, a resilient woody species. Intercropping improved Si uptake in grapevine leaves and unveiled novel patterns of Si distribution in woody tissues and plant metabolic responses. Chapter 5 surveys selected Mediterranean maquis species to assess variations in plant and soil Si concentration. Analyses highlight site-specific nutrient dynamics and plant–soil interactions, providing deeper insights into Si in semi-arid ecosystems. Collectively, these integrated studies underscore Si’s importance in plant and ecosystem resilience, offering a framework for developing Si-based AE and AF systems. Further research into Si transporters, microbiology, and rhizosphere mechanisms could deepen our understanding of Si processes and their broader implications in agroecosystems.