Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm n"Variation of morphological traits in natural populations of maritime pine (Pinus pinaster Ait.) in Morocco"ghiệp Original article đề tài: | Ann. For. Sci. 63 2006 83-92 INRA EDP Sciences 2006 DOI forest 20050100 83 Original article Variation of morphological traits in natural populations of maritime pine Pinus pinaster Ait. in Morocco Nadya WAHIDa b Santiago C. González-Martínezc Ismail El HADRAMIb Abdelali BouLLia a Laboratoire d analyse et de valorisation des ressources environnementales Département de Biologie Université Cadi Ayyad Faculté des Sciences et Technique de Béni Mellal BP 523 Béni Mellal Morocco b Laboratoire de physiologie végétale Département de Biologie Université Cadi Ayyad Faculté des Sciences Semlalia BP 2390 40000 Marrakech Morocco c Unidad de Genética Forestal CIFOR-INIA Carretera de La Coruna km 28040 Madrid Spain Received 2 June 2004 accepted 26 May 2005 Abstract - Pinus pinaster Ait. is the main species used for reforestation in Morocco both in mountain and low lands areas. However little information is available about its intraspecific variation and adaptability in this range. This work studied the morphological variation of nine native populations covering the distribution area of maritime pine in Morocco Rif Middle Atlas and High Atlas . Thirteen morphological and anatomical traits from cones length and width seeds length width thickness and weight seed wings length and width and needles length width thickness and the number of stomata rows on the dorsal and convex faces of the needle were measured in 232 trees. A Principal Component Analysis was used to explain the variation observed in four principal components related to cone PCA3 seed PCA1 and needle PCA2 and PCA4 traits. Variability in morphological traits was high in Moroccan populations of maritime pine and significant differences among populations were found. Moreover cone and needle traits showed clinal variation responding to latitude altitude gradients. A hierarchical classification of all populations led to the formation of three major groups i Mediterranean coastal populations ii southeastern Rif .