Leaf senescence in tomato mutants as affected by irradiance and phytohormones

Autor(es)

Carvalho, R. F. ^[1] ; Monteiro, C. C. ^[1] ; Caetano, A. C. ^[2] ; Dourado, M. N. ^[2] ; Gratao, P. L. ^[1] ; Haddad, C. R. B. ^[3] ; Peres, L. E. P. ^[2] ; Azevedo, R. A. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Estadual Paulista, Fac Ciencias Agr & Vet, BR-14884900 Jaboticabal, SP - Brazil

^[2] Univ Sao Paulo, Escola Super Agr Luiz de Queiroz, BR-13418900 Piracicaba, SP - Brazil

^[3] Univ Estadual Campinas, Inst Biol, BR-13083970 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Biologia Plantarum; v. 57, n. 4, p. 749-757, DEC 2013.
• Citações Web of Science: 11

Resumo

We explored the interaction between radiation of different wavelength and jasmonic acid (JA) or brassinosteroids (BR) on leaf senescence-induced oxidative stress. Three approaches were used: 1) jasmonic acid insensitive1-1 (jai1-1) and brassinosteroid-deficient {[}dumpy (dpy)] mutants were treated with red (R) or far-red (FR) radiation; 2) phytochromedeficient aurea (au) and high pigment-1 (hp-1) (radiation exaggerated response) mutants were treated with methyl jasmonate (MeJA) or epibrassinolide (epiBL); and 3) double mutants au jai1-1 and au dpy were produced. Leaf chlorophyll content, lipid peroxidation, and antioxidant enzyme activities were determined. After senescence induction in detached leaves, we verified that the patterns of chlorophyll degradation of hormonal and photomorphogenic mutants were not significantly different in comparison with original cv. Micro-Tom (MT). Moreover, there was no significant change in lipid peroxidation measured as malondialdehyde (MDA) production, as well as catalase (CAT), ascorbate peroxidase (APX), and glutathione reductase (GR) activities in the hormonal mutants. Exogenous BR increased CAT and APX activities in MT, au, and hp-1. As concerns the double mutants, severe reduction in H2O2 production which was not accompanied by changes in MDA content, and CAT and APX activities was observed during senescence in au dpy. The results suggest that JA and BR do not participate in light signaling pathway during leaf senescence-induced oxidative stress. (AU)

• Processo FAPESP: 09/54676-0 - Estresse oxidativo induzido por metais: novas abordagens
• Beneficiário: Ricardo Antunes de Azevedo
• Linha de fomento: Auxílio à Pesquisa - Temático
• Processo FAPESP: 08/53065-4 - Interação de fitocromo com ácido jasmônico e com brassinoesteróide no controle da senescência foliar em Lycopersicon esculentum Mill. syn. Solanum lycopersicum L., cultivar Micro-Tom
• Beneficiário: Rogério Falleiros Carvalho
• Linha de fomento: Bolsas no Brasil - Pós-Doutorado