ANEUPLOIDS CULTIVATED IN VITRO AS A SOURCE OF GENETIC VARIABILITY FOR APPLE

Aneuploids from ‘Jonagold’ (3n) x ‘McIntosh Wijcik’ (2n) crosses survived after in vitro germination, classical micropropagation and micrografting on pre-acclimatized rootstocks.
From flow cytometry data of seeds collected in the orchard from H48 and H123, a genetic variability was detected from diploïdy to tetraploïdy, together with slight different levels of aneuploidy.
The progeny of H48, when fingerprinted by microsatellite markers, was shown not to be apomictic.
Adventitious budding induced polyploidisation and cytochimerism on aneuploids.
Most cytochimeras from H48 were revealed to be unstable and led to different ploidy patterns in the regenerants of secondary adventitious budding: homogeneous ploidy, new aneuploidy and new cytochimerism.
The reversion of cytochimeras could be under efficient control.
Our data demonstrated that the genetic variability induced by the in vitro treatment of aneuploid genotypes was clearly expressed, frequent and concerned small parts of the genome while viable plants even aneuploids, can be provided for classical breeding.

XI Eucarpia Symposium on Fruit Breeding and Genetics

PH. Druart

Malus x domestica, aneuploidy, cytochimera, adventitious bud regeneration, flow cytometry, microsatellites

https://doi.org/10.17660/ActaHortic.2004.663.82