Lécolier A. auteur aut IRD Noirot Michel auteur aut IRD Escoute J. auteur aut IRD Chrestin Hervé auteur aut IRD Verdeil J. L. auteur aut IRD text journalArticle eng text/pdf born digital access The current article presents the investigations into the effect of the laurina mutation on the functioning and size of the shoot apical meristem (SAM) in Coffea arabica. This monolocus and Mendelian mutation is known to have pleiotropic effects on tree shape and dwarfism. A comparison between the wild type C. arabica var. Bourbon and its natural dwarf mutant C. arabica var. laurina, also called Bourbon pointu, was carried out leading to three main results: (1) the effects appeared immediately after the emergence of the buttress but did not affect the dome-shaped SAM (size and shape); (2) the effects were located at the peripheral zone and maintained subsequently within the leaf primordia; (3) the effects consisted of reduction in both the size of primordia and the height of incipient internode, consequently resulting in dwarfism of mature leaves and internodes. By contrast, the laurina mutation had no effect on the relationship between the phyllochron and the plastochron, the decussate and opposite phyllotaxis, and the relative timing of SAM functioning within the plastochron. specialized Coffea arabica Laurina mutation Primordia Leaf size Shoot apical meristem 076 23 3 673-682 2009 0931-1890 https://www.documentation.ird.fr/hor/fdi:010046104 10.1007/s00468-008-0311-y 0931-1890 [F B010046104] https://www.documentation.ird.fr/hor/fdi:010046104 https://www.documentation.ird.fr/intranet/publi/2009/06/010046104.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2009-07-08 2017-08-23 fdi:010046104 fre