DIVERSITY IN ROSA RUGOSA × ROSA HYBRIDA INTERSPECIFIC CULTIVARS

Modern roses represent a relatively narrow gene pool resulting in poor disease and abiotic stress resistance.
The diploid species Rosa rugosa Thunb. shows high disease resistance and tolerance to environmental stress conditions.
However, their ornamental characteristics are in need of improvement.
Interspecific crosses between Rosa hybrida and Rosa rugosa are difficult to obtain, but they could potentially yield resistant varieties with valuable ornamental properties.
Eight Latvian varieties that resulted from crosses with R. rugosa type roses and six parents were analyzed with 21 microsatellite markers to confirm the results of interspecific crosses and to identify presence of modern rose genetic material.
According to preliminary data, the majority of varieties that resulted from interspecific crosses showed strong presence of R. rugosa gene pool both in terms of genotype and phenotype.
However, two crosses, ‘Abelzieds’ (R. rugosa ‘Alba’ × ‘Poulsen’s Pink’) and ‘Zaiga’ (R. rugosa ‘Plena’ × ‘Flammentanz’), exhibited presence of Floribunda and Climbing rose characteristics.
Phenotypically, only one interspecific cultivar, ‘Zaiga’, showed modern garden rose type flower color and leaf shape.
Nevertheless, both ‘Abelzieds’ and ‘Zaiga’ could be used for breeding owing to good disease resistance, rigorous growth, and ornamental characteristics.

XXIII International Eucarpia Symposium, Section Ornamentals: Colourful Breeding and Genetics

A. Sparinska, R. Zarina, N. Rostoks

Rosa, microsatellite genotyping, disease resistance, interspecific hybridization, blackspot

https://doi.org/10.17660/ActaHortic.2009.836.15