Adjustments in photosynthetic pigments, PS II photochemistry and photoprotection in a tropical C4 forage plant exposed to warming and elevated [CO2]

Autor(es)

Approbato, Andressa Uehara ; Contin, Daniele Ribeiro ; Oliveira, Eduardo Augusto Dias de ; Habermann, Eduardo ; Cela, Jana ; Pinto-Marijuan, Marta ; Munne-Bosch, Sergi ; Martinez, Carlos Alberto

• Tipo de documento: Artigo Científico
• Fonte: Plant Physiology and Biochemistry; v. 194, p. 16-pg., 2023-01-01.

Resumo

Global climate change will impact crops and grasslands, affecting growth and yield. However, is not clear how the combination of warming and increased atmospheric carbon dioxide concentrations ([CO2]) will affect the photosystem II (PSII) photochemistry and the photosynthetic tissue photoinhibition and photoprotection on tropical forages. Here, we evaluated the effects of elevated [CO2] (similar to 600 mu mol mol(-1)) and warming (+2 degrees C increase temperature) on the photochemistry of photosystem II and the photoprotection strategies of a tropical C4 forage Panicum maximum Jacq. grown in a Trop-T-FACE facility under well-watered conditions without nutrient limitation. Analysis of the maximum photochemical efficiency of PSII (F-v/F-m), the effective PSII quantum yield Y(II), the quantum yield of regulated energy dissipation Y(NPQ), the quantum yield of non-regulated energy dissipation Y(NO), and the malondialdehyde (MDA) contents in leaves revealed that the photosynthetic apparatus of plants did not suffer photoinhibitory damage, and plants did not increase lipid peroxidation in response to warming and [CO2] enrichment. Plants under warming treatment showed a 12% higher chlorophyll contents and a 58% decrease in alpha-tocopherol contents. In contrast, carotenoid composition (zeaxanthin and beta-carotene) and ascorbate levels were not altered by elevated [CO2] and warming. The elevated temperature increased both net photosynthesis rate and aboveground biomass but elevated [CO2] increased only net photosynthesis. Adjustments in chlorophyll, de-epoxidation state of the xanthophylls cycle, and tocopherol contents suggest leaves of P. maximum can acclimate to 2 degrees C warmer temperature and elevated [CO2] when plants are grown with enough water and nutrients during tropical autumn-winter season. (AU)

• Processo FAPESP: 08/58075-8 - Miniface climate-change impact experiment to analyze the effects of elevated CO2 and warming on photosynthesis, gene expression, biochemistry, growth, nutrient dynamics and yield of two contrasting tropical forage species
• Beneficiário: Carlos Alberto Martinez y Huaman
• Modalidade de apoio: Auxílio à Pesquisa - Programa de Pesquisa sobre Mudanças Climáticas Globais - Temático
• Processo FAPESP: 14/00317-7 - Fluxo de carbono e de gases estufa em ecossistema de pastagem composta por Panicum maximum Jacq. e Stylosanthes capitata Voegel cultivadas sob elevada concentração de CO2 e elevada temperatura em sistemas FACE/T-FACE
• Beneficiário: Eduardo Augusto Dias de Oliveira
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado