Croissance rythmique endogegrave;ne de la feuille deGuarea guidonia(Meacute;liaceacute;es): Eacute;tude preacute;liminaire expeacute;rimentale

摘要

The composed pennate adult leaf ofGuarea guidonia(Meliaceae) has a multiannual rythmic growth shown by the successive sequential setting of leaflet pairs. This is demonstrated at the level of the foliar central vein by the differentiation of periodic rings in the wood. Microsurgically isolated foliar primordia produced large leaves, the tops of which supported several foliar sequences. Early removal of foliar primordia suppressed the endogenous rythmic growth pattern and the functioning of the foliar apex became continuous. Isolated cuttings of the composed leaf were readily rooted, the rythmic growth being maintained. This was also possible with cuttings of isolated nodes. Data show that rooted cuttings of this plant could be used as a model for the study of endogenous rythmic growth of woody plants.Key words:Guarea guidonia, composed leaf, endogenous rythmic growth, root cutting. Journal translation