RECIPROCAL CROSS-COMPATIBILITY IN CUT ROSE BREEDING

Abstract

Rose breeding companies have developed new rose varieties in response to increasing demands for color, fragrance and shapes. Hybridization is one of the most important methods of creating new rose variations. Breeders focus on fertility, reproduction, and a high number of seeds per fruit. In the present study, four Rosa genotypes ('Jumilia', 'Black Magic', 'Tineke', 'Black Baccara') were crossed to assess genetic compatibility, seed formation potential and germination rate. The results showed that all genotypes were tetraploid, and pollen germination varied from 11.36% to 23.41%. The highest crossability rate (94.44%) was found in the 'Black Baccara' x 'Jumilia' combination, followed by 'Black Magic' x 'Jumilia' (60%). The highest seedyields were obtained in 'Jumilia' x 'Tineke' (60.50). 'Tineke' x 'Jumilia' (43.74) showed the second highest number of seeds per fruit, whereas limited success was determined in cross 'Jumilia' x 'Black Magic (2.25). The maximum germination percentage was found in 'Jumilia' when crossed with 'Tineke'. Significant variations were recorded for the weight of hips and weight of fruit. The PCA-biplot results indicated a positive correlation between crossability rate and seed production efficiency. Overall, the choice of parents was crucial for the crossability indices, which are the average crossability rate and seed production efficiency.