GENOTYPIC ABILITY OF ROSA HYBRIDA L. TO PRODUCE PARTHENOGENETIC PLANTS AFTER POLLINATION WITH IRRADIATED POLLEN

The fertility of the parthenogenetic diploid roses is extremely variable but generally very weak. So, for applied breeding purposes, the haploidization method of Rosa hybrida must be carried out with a selection object of fertility and consequently requires to work with sufficient numbers.

We observed that the main optimization factor of the haploidization was the genotypic ability to parthenogenesis (Meynet et al., 1995). The implemented method consists in activating the embryo development after a semblance of fertilization by irradiated pollen which is able to germinate and get in contact with the ovule but without exchange of the male nucleus contents. The first stages of the pollination are the same wether the polllen is irradiated or not, now, we know that they cause important effects on the yield of fertilized achenes (Gudin and Arène, 1991). So, we will try to establish a correlation between parthenogenetic and fertilized achene production ability.