Dormancy breakage of Stylosanthes humilis seeds by aluminium

• Autor(a) principal: Ribeiro, Dimas M.
• Data de Publicação: 2010
• Outros Autores: Mapeli, Ana M., Carnelossi, Marcelo A. G., Delatorre, Carla A., Barros, Raimundo S.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://dx.doi.org/10.1017/S0960258510000164; http://www.locus.ufv.br/handle/123456789/23309
• topic: Aluminium; Dormancy; Ethylene; Reactive oxygen species; Stylosanthes humilis; Seeds

Physiological dormancy of scarified seeds of Townsville stylo (Stylosanthes humilis HBK) was released by acidic aluminium (Al3+) solution. Antiethylenic substances inhibited germination of low-pH-stimulated dormant seeds, with a correspondingly low ethylene production and low activity of 1-aminocyclopropane-1-carboxylate (ACC) oxidase in seeds. On the other hand, antiethylenic substances did not decrease the germination of Al3+-stimulated seeds, but ACC oxidase activity and ethylene production by the seeds was decreased to a large extent. These data provide evidence that dormancy breakage by Al3+ differs from that caused by low pH and is not associated with ethylene production. Similarly to Al3+ action, methyl viologen (MV), a reactive oxygen species-generating compound, broke dormancy of Townsville stylo seeds. Sodium selenate and N-acetyl cysteine, antioxidant compounds, largely decreased germination of MV- and Al3+-stimulated dormant seeds. Altogether these data point to oxidative radicals constituting key molecules in the chain of events triggered by Al3+ leading to dormancy breakage.