Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp Original article đề tài: The route of the pollen tube from stigma to ovule in Populus nigra : a new look | Ann. Sci. For. 1987 44 2 259-264 The route of the pollen tube from stigma to ovule in Populus nigra a new look M. VILLAR M. GAGET et c. DUMAS INRA Station d Amelioration des Arbres forestiers Ardon F 45Ì60 Olivet Université Cl. Bernard Lyon I. RCAP UM CNRS 380024 F 60622 Villeurbanne Cedex Summary The complete progress of the Populus nigra pollen tube from the stigma surface to the ovule micropyle of p. nigra has been examined recently by the classical ABF method and by a new scanning electron microscope connected to a cryogenic preparation system. Key words Pollen stigma ovule. Populus. 1. Introduction Hybridization programmes in Populus are limited by incompatibility barriers whose cellular sites and molecular mechanisms have not yet been defined. In spite of studies dealing with incompatibility in Populus in the last decade Willing Pryor 1976 Stettler Ager 1984 reproduction events especially intra-pistillar phenomena have not been clarified yet. During an investigation of these events we have examined the pollination pathway especially the behaviour of the pollen tube from the stigma surface to the ovule. This work is part of a programme on interspecific incompatibility in Populus involving both the INRA Station d Amelioration des Arbres forestiers Orleans France and the Université de Lyon Laboratoire de Reconnaissance cellulaire et d Amelioration des Plantes Villeurbanne France Gaget et al. 1984 b . 2. Materials and methods Branches of Populus nigra bearing flower buds were forced and flowers were matured in growth chambers at the Université de Lyon Villeurbanne France . Before pollination pollen viability was checked using the FCR test Fluorochromatic Reaction Heslop-Harrison Heslop-Harrison 1970 . 260 M. VILLAR M. GAGET c. DUMAS The progress of the pollen tube was monitored on the stigmatic surface and in the ovary cavity by scanning electron microscope SEM JEOL 35 CF connected to an EMSCOPE SP 2000 cryogenic system of the Centre de Microscopie Electronique .
