Preliminary evaluation results of new plum cultivars in a dense planting

Sixteen new plum cultivars mostly bred in Germany were tested together with several standards in a high density experimental orchard established at Holovousy in the spring of 2004 with spacing 5 × 1.5 m. Trees were trained as spindles on St. Julian A rootstock. In the orchard the following characteristics were evaluated: tree vigour based upon measuring of trunk-cross section area and canopy volume, yields, time of flowering, time of fruit ripening and basic parameters of fruit quality. The highest yields and precocity of fruiting were recorded on cultivars Tophit, Jojo, Elena, and President, whereas the least productive were Ruth Gerstetter, Anna Späth, and Topgigant Plus. Cultivars Katinka, Jojo, Topper, and Empress had the highest values of yield efficiency whilst the lowest ones were recorded on Topgigant Plus and Anna Späth. All evaluated cultivars were characterized by mean start of fruit ripening and length of harvest period. Topgigant Plus had the largest fruits (mean 75.9 g) followed by Bluefre, Empress and Tophit, whereas the smallest ones were recorded in Katinka, Gabrovská and Valjevka. The highest scores for fruit quality were given to Hanita, Tophit and Presenta. New cultivar Tophit was the most remarkable regarding all evaluated characteristics including its time of ripening that would prolong the season of commercially grown fresh fruit cultivars for use in the Czech Republic.