UV light and adaptive divergence of leaf physiology, anatomy, and ultrastructure drive heat stress tolerance in genetically distant grapevines

• DOI: 10.3389/fpls.2024.1399840
• Publication Date: 2024-06-18T05:41:17Z
• Authors: Ana Fernandes de ...; Giovanni Kamal Piga; Soumiya Najoui; Giovanna Becca; Salvatore Marceddu; Maria Pia Rigoldi; Daniela Satta; Simonetta Bagella; Giovanni Nieddu
• Keywords: 0301 basic medicine; 03 medical and health sciences; stress tolerance; Vitis vinifera L.; Plant culture; Cannonau; Plant Science; UV-B light; Carignano; in vivo metabolite dynamics; Cannonau; Carignano; in vivo metabolite dynamics; leaf cell barriers; leaf reflectance; stress tolerance; UV-B light; Vitis viniferaL; SB1-1110

The genetic basis of plant response to light and heat stresses had been unveiled, different molecular mechanisms leaf cell homeostasis keep high physiological performances were recognized in grapevine varieties. However, the ability develop stress tolerance strategies must be further elucidated since morpho-anatomical traits involved may vary with genotype × environment combination, intensity, duration. A 3-year experiment was conducted on potted plants Sardinian red cultivars Cannonau (syn. Grenache) Carignano Carignan), exposed prolonged inside a UV-blocking greenhouse, either submitted low daily UV-B doses 4.63 kJ m −2 d −1 (+UV) or 0 (−UV), compared control (C) solar radiation (4.05 average dose). Irrigation supplied avoid water stress, canopy thermal microclimate monitored continuously. Heat exceeded one-third duration greenhouse 6% C. In vivo spectroscopy, including reflectance fluorescence, allowed for characterizing patterns metabolites oxidative protection. showed lower stomatal conductance under C (200 mmol s ) but more than twice values (400 900 ), where use efficiency reduced similarly both Under severe −UV, sharper decrease primary photochemical activity higher pigment indexes mass area. increased pigments, especially Carignano, regulatory prevent damage observed cross-sections. induced chloroplast swelling, plastoglobule diffusion, accumulation secretion deposits varieties, aggravated −UV by vacuolation, membrane dilation, diffused blade spot swelling. Conversely, UV-B, wall barriers calcium oxalate crystals proliferated mesophyll cells. These responses suggest an adaptive divergence among light. Further research biodiversity, heat, interactions give new insights extent improve viticulture climate change hotspots.