The production of 2n pollen in rose |
| |
Authors: | L Crespel S C Ricci S Gudin |
| |
Institution: | 1. Meilland International, Domaine Saint André, F-83340, Le Cannet des Maures, France 2. Institut Méditerranéen d’Ecologie et Paléoécologie (IMEP),Faculté de Saint Jér?me, Université Paul Cézanne (Aix-Marseille III), Service 442, Av. Escadrille Normandie-Niemen, F-13397, Marseille Cedex 20, France
|
| |
Abstract: | Based on the size differences found between haploid and diploid pollen produced by diploid and tetraploid rose cultivars, respectively, 2n pollen producers were identified in a population of 53 diploid hybrids from a cross between a dihaploid rose, derived from the haploidization of a tetraploid modern cultivar and the diploid species R. wichuraiana. Frequency of 2n pollen producers was estimated in 2002, 2003 and 2004. Highly variable frequencies were found i) within population; ii) during years of observation (between years and between different months in the same year). The variation of 2n pollen production could be related to environmental fluctuations. A cytological analysis of male meiosis was carried out in 10 hybrids randomly chosen. Among meiotic abnormalities leading to 2n pollen formation, triads (containing a 2n microspore at one pole and two n microspores at the other) resulting from abnormal spindle geometry were frequently observed. The mode of 2n pollen formation is genetically equivalent to a First Division Restitution (FDR) mechanism. FDR 2n pollen transmits a high percentage of the heterozygosity from the diploid parent – 2n pollen producer-to the tetraploid offspring. |
| |
Keywords: | Rosa Dihaploid 2n gametes Meiotic abnormalities Sexual polyploidization |
本文献已被 SpringerLink 等数据库收录! |
|