Moderate warm temperature improves shoot growth, affects carbohydrate status and stimulates photosynthesis of sweet orange plants

Autor(es)

Rafael Vasconcelos Ribeiro ^[1] ; Eduardo Caruso Machado ^[2] ; Erick Espinoza-Núñez ^[3] ; Rômulo Augusto Ramos ^[4] ; Daniela Favero São Pedro Machado ^[5]

Afiliação do(s) autor(es)

^[1] Agronomic Institute. Center for Research and Development in Ecophysiology and Biophysics. Laboratory of Plant Physiology Coaracy M. Franco - Brasil

^[2] Agronomic Institute. Center for Research and Development in Ecophysiology and Biophysics. Laboratory of Plant Physiology Coaracy M. Franco - Brasil

^[3] Agronomic Institute. Center for Research and Development in Ecophysiology and Biophysics. Laboratory of Plant Physiology Coaracy M. Franco - Brasil

^[4] Agronomic Institute. Center for Research and Development in Ecophysiology and Biophysics. Laboratory of Plant Physiology Coaracy M. Franco - Brasil

^[5] Agronomic Institute. Center for Research and Development in Ecophysiology and Biophysics. Laboratory of Plant Physiology Coaracy M. Franco - Brasil

• Tipo de documento: Artigo Científico
• Fonte: Brazilian Journal of Plant Physiology; v. 24, n. 1, p. 37-46, 2012-00-00.

Resumo

Citrus plants were grown under two thermal conditions for evaluating carbon metabolism acclimation to moderate warm temperature (30/20ºC, day/night), and its likely impact on plant growth. As reference, plants were grown at 25/20ºC, in which they were subjected to optimum temperature for photosynthesis during the diurnal period (25ºC). Higher photosynthetic rates were found at 30/20ºC as compared to 25/20ºC in both mature and young leaves, being this response associated with higher stomatal conductance. After 30 days of thermal treatment, plants grown at 30/20ºC presented higher shoot growth as compared to those at 25/20ºC. The carbohydrate concentration decreased in stem and root tissues, while it increased in leaf tissues under moderate warm conditions. Both mature and young leaves showed higher photoassimilate consumption/exportation at 30/20ºC than at 25/20ºC. In this paper, we have proven that citrus plants present a positive balance in carbon metabolism as an acclimation mechanism to temperature changes, with plants presenting increased photosynthesis. Such photosynthetic acclimation was associated with improved vegetative growth, being both mature and young tissues sensitive to changes in thermal regimen. (AU)

• Processo FAPESP: 05/57862-8 - Florescimento e frutificação em laranjeira Valência: aspectos anatômicos, fisiológicos, bioquímicos e moleculares
• Beneficiário: Marcelo Carnier Dornelas
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 02/08480-7 - Variação sazonal da fotossíntese, relações hídricas e do teor de carboidratos em laranjeira Valência
• Beneficiário: Rafael Vasconcelos Ribeiro
• Modalidade de apoio: Bolsas no Brasil - Doutorado