|Authors: ||C. Botez, R. Sestras, M. Ardelean, D. Pamfil, B. Patrascu, A. Sestras|
|Keywords: ||apple, scab, breeding, selection, marker, Vf gene|
Apple scab, caused by Venturia inaequalis, is an important disease, which has a major negative impact in fruit production.
Phenotypic selection for scab resistance in apple seedling populations (F1), derived from semidiallel hybridizations among four apple cultivars (‘Liberty’ and ‘Florina’ - scab resistant; ‘Starkrimson’ and ‘Golden Spur’ - scab susceptible), was completed by marker-assisted selection.
The conventional selection methods for apple scab resistance can be greatly improved using genetic markers tightly linked with scab resistance genes.
PCR analysis conducted with AL-07, AM-19, and Ul400 specific primers, usually confirmed the presence or absence of Vf allele for scab resistance in resistant or sensitive plantlet isolated by phenotypic selection.
The co-dominant marker AL-07 was very useful to discriminate homozygous from heterozygous plantlet for that locus.
Using Bulk Segregant Analysis we have attempt to find RAPD markers linked with other resistance genes to apple scab.
Although we have obtained a significant polymorphism between resistant and susceptible parental seedlings, for few primers we have found RAPD molecular markers linked in couplings state with putative scab-resistant genes.
In such a favourable situation, the selection for scab resistance among hybrid seedlings segregates, using molecular markers, usually confirmed phenotypic selection even for some seedlings lacking Vf allele, so these markers could be linked with other scab-resistant genes.
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