Cytological basis for a tetraspory in Cupressus sempervirens L. megagametogenesis and its implications in genetic studies |
| |
Authors: | M. El Maâtaoui C. Pichot H. Alzubi N. Grimaud |
| |
Affiliation: | (1) Université d’Avignon, Laboratoire de Biologie Végétale Expérimentale, 33 rue L. Pasteur, 84000 Avignon, France Fax: +33(0) 4 90 14 4459 E-mail: mohamed.elmaataoui@univ.avignon.fr, FR;(2) INRA, Unité de Recherches Forestières Méditerranéennes, Equipe de Génétique, Av. Vivaldi, 84000 Avignon, France, FR |
| |
Abstract: | The processes of megasporogenesis and early megagametogenesis were cytologically investigated in Cupressus sempervirens L. in order to elucidate, at the cellular level, the origin of the megagametophyte. After pollination, sporogenous tissue developed in the chalazal region of the nucellus, but only one megaspore mother cell differentiated and divided meiotically without cell-wall formation. This led to the development of a cell with four nuclei which directly functioned as a megaspore. The C. sempervirens megagametophyte is thus tetrasporic, in contrast to the majority of conifers where the megagametophyte is monosporic. The consequenses of this observation are discussed from a genetics point of view. Received: 15 August 1997 / Accepted: 19 September 1997 |
| |
Keywords: | Cupressus sempervirens Cytology Megasporogenesis Megagametogenesis Genetics |
本文献已被 SpringerLink 等数据库收录! |
|