Rootstocks induce contrasting photosynthetic responses of orange plants to low night temperature without affecting the antioxidant metabolism

Autor(es)

Sao Pedro Machado, Daniela Favero ^[1] ; Ribeiro, Rafael Vasconcelos ^[2] ; Gomes da Silveira, Joaquim Albenisio ^[3] ; Magalhaes Filho, Jose Rodrigues ^[1] ; Machado, Eduardo Caruso ^[1]

Afiliação do(s) autor(es)

^[1] Inst Agron IAC, Lab Plant Physiol Coaracy M Franco, Campinas, SP - Brazil

^[2] Univ Estadual Campinas UNICAMP, Plant Biol Dept, Inst Biol, Campinas, SP - Brazil

^[3] Univ Fed Ceara, Biochem & Mol Biol Dept, Fortaleza, Ceara - Brazil

• Tipo de documento: Artigo Científico
• Fonte: THEORETICAL AND EXPERIMENTAL PLANT PHYSIOLOGY; v. 25, n. 1, p. 26-35, 2013.
• Citações Web of Science: 8

Resumo

Low temperatures negatively impact the metabolism of orange trees, and the extent of damage can be influenced by the rootstock. We evaluated the effects of low nocturnal temperatures on Valencia orange scions grafted on Rangpur lime or Swingle citrumelo rootstocks. We exposed six-month-old plants to night temperatures of 20 degrees C and 8 degrees C under controlled conditions. After decreasing the temperature to 8 degrees C, there were decreases in leaf CO2 assimilation, stomatal conductance, mesophyll conductance and CO2 concentration in the chloroplasts, in plant hydraulic conductivity and in the maximum electron transport rate driven ribulose-1,5-bisphosphate (RuBP) regeneration in plants grafted on both rootstocks. However, the effects of low night temperature were more severe in plants grafted on Rangpur rootstock, which also presented reduction in the maximum rate of RuBP carboxylation and in the maximum quantum efficiency of the PSII. In general, irreversible damage due to night chilling was found in the photosynthetic apparatus of plants grafted on Rangpur lime. Low night temperatures induced similar changes in the antioxidant metabolism, preventing oxidative damage in citrus leaves on both rootstocks. As photosynthesis is linked to plant growth, our findings indicate that the rootstock may improve the performance of citrus trees in environments with low night temperatures, with Swingle rootstock improving the photosynthetic acclimation in leaves of orange plants. (AU)

• Processo FAPESP: 07/53520-0 - Resposta da fotossíntese a variação da temperatura no sistema radicular em laranjeira Valência
• Beneficiário: José Rodrigues Magalhães Filho
• Linha de fomento: Bolsas no Brasil - Mestrado
• Processo FAPESP: 05/57862-8 - Florescimento e frutificação em laranjeira Valência: aspectos anatômicos, fisiológicos, bioquímicos e moleculares
• Beneficiário: Marcelo Carnier Dornelas
• Linha de fomento: Auxílio à Pesquisa - Temático
• Processo FAPESP: 06/59382-6 - Respostas da fotossíntese a baixa temperatura noturna em laranjeira "valência"
• Beneficiário: Daniela Favero São Pedro Machado
• Linha de fomento: Bolsas no Brasil - Mestrado