During the years 2012 to 2014 some research connected with highbush blueberry was taken. It described phenotypic and genotypic variability of 19 cultivars of highbush blueberries grown in the Lublin region. The cultivars included in the study were: ‘Bluecrop’, ‘Bluejay’, ‘Blueray’, ‘Bonifacy’, ‘Bonus’, ‘Brigitta Blue’, ‘Chandler’, ‘Chanticleer’, ‘Croatan’, ‘Darrow’, ‘Duke’, ‘Earliblue’, ‘Herbert’, ‘Jersey’, ‘Northland’, ‘Nelson’, ‘Patriot’, ‘Toro’ and ‘Spartan’. The flowering of highbush blueberry can be observed from the end of April to the beginning of June. Meanwhile, ripening depended on cultivar, starting from June 29^th and finishing by September 7^th. The strongest vegetative growth was characteristic of ‘Bluecrop’ cultivar on the oldest plantation – Niemce, whereas on the Spiczyn 1 – ‘Darrow’ cultivar, and ‘Patriot’ proved to be the best yielding cultivar on the youngest plantation. In the study, berries of the ‘Chandler’ cultivar were the largest, and berries of the ‘Northland’ cultivar were considered to be the smallest. To evaluate the tested cultivars at the DNA level RAPD markers were used. The set of 9 analysing primers generated a total of 91 fragments of which 81 (89%) were polymorphic. The average genetic similarity determined on the basis of the similarity matrix of RAPD markers was 0.41. Application of the UPGMA method for grouping varieties showed the highest distinction of cultivars: ‘Croatan’, ‘Chanticleer’, ‘Herbert’ and ‘Brigitta Blue’, in relation to the others. Among the tested cultivars genetic variation was detected since genetic similarity ranged from 0.22 to 0.60. Nevertheless the same cultivars grown in different locations demonstrated genetic identity.

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