Desenvolvimento de plântulas de sobreiro com maior vitalidade associada à função de fungos micorrízicos (FM) e aquaporinas: promovendo a conservação do importante ecossistema socioeconómico do montado

The sustainability of the montado ecosystem has been reducing due to decreased cork oak density, low tree regeneration rate and high seedlings mortality. Drought stress is a primary challenging factor for cork oak decline, threatening the balance of this ecosystem. Artificial reforestation offers a better choice, however it needs specific strategies to avoid transplantation shock and soil degradation near roots. Establishing a buffer zone near roots, like promoting roots-mycorrhizal association, will avoid soil degradation. The symbiotic relationship between cork oak and mycorrhizal fungi (MF) provides a promising strategy to enhance nutrient uptake and drought tolerance. However, selecting suitable MF inoculants can be delicate due to their niche-dependency. Thus, it required a profound understanding of underlying mechanisms of plant-MF relations. Significance of water channels, aquaporins (AQPs) during plant-microbe interaction has been associated for better stress tolerance by improving water and nutritional acquisition in host plants. Lack of knowledge about cork oak AQPs limits the broad understanding of water transport and associated stress tolerance mechanisms in cork oak at the molecular level, specifically during MF association. Our preliminary findings suggest AQPs play a crucial role in cork oak, influencing water and small molecule transport. It inspires the novel approach of the present proposal to explore the molecular mechanisms related to AQPs role during mycorrhiza association. The project also emphasizes the sustainability and conservation of cork oak ecosystems by replacing chemical fertilizers. Specifically, the project includes four major objectives based on novel concepts and interdisciplinary approaches: 1. Selection of beneficial MF (AMF/EMF) for the growth and survival of cork oak seedlings in drought-prone and arsenic-contaminated areas 2. Determination of role of cork oak aquaporins in mycorrhiza interaction by their differential expression under stress conditions and tissue-specific immunolocalization of AQP subfamilies 3. Cloning and expression of identified cork oak AQPs in yeast expression system to avoid the varied temporal and spatial response of AQPs in plants 4. Functional characterization for water and atypical substrates (like glycerol and arsenic) transport of cork oak AQPs, expressed in yeast. To determine their individual role in response to stress conditions and determination of their regulatory factors and stress tolerance mechanisms 5. Applying the identified regulatory factors (pH, light, temperature) at young seedlings of cork oak for providing practical guidelines for nurseries for optimum AQP expression and further resilience in the field The interdisciplinary collaboration of research groups enhances the scope of the project. It will combine the expertise in Plant Molecular Biology especially in cork oak (L Morais, ISA and L Marum, CEBAL) and Plant Physiology and Biochemistry [LCarvalho and FSabir (ISA)], mycorrhiza association (LMarum, CEBAL), Yeast Molecular Biology and Physiology (CPrista, FSabir (ISA), and Biophysics (CPrista (ISA), FSabir (ISA), and GSoveral (consultant, FARM-ID).