A PRIMARY STUDY ON GROWTH AND DEVELOPMENT OF HIGHBUSH BLUEBERRIES IN CENTRAL POLAND

The results of 5-year studies on growth and development of seven highbush blueberry cultivars under the climate conditions of Central Poland are presented. The experiment was established in 1971. Bushes were planted in special concrete rings which were sunk into the ground. Three types were used: (1) podzolic, collected from the farm field with peat-moss at ratio 3:1; (2) forest podzolic, top layer; (3) peat-moss with sand at ratio 3:1. The following highbush blueberry cultivars were tested: Blueray, Bluecrop, Rekord, Concord, Darrow, Lateblue, and Herbert. The vegetative growth of the blueberry bushes was evaluated on the basis of their total terminal growth, number of terminals, and volume of bushes. All data were subjected to statistical analysis.

It was found that Rekord and Concord cultivars produced the highest total terminal growth. In the case of the number of terminals, the only significant difference was noted for Rekord and Lateblue. The plants grown on the peat-moss substrate produced significantly higher total terminal growth, if compared to the other treatments.

The yield performance of the investigated cultivars is presented as average of yield per bush, weight per 100 berries, and cup count. The best bearers were Lateblue, Rekord, and Concord. In regard to size of the berry, the largest were produced by cultivars in the following order: Darrow, Blueray, Bluecrop, Lateblue, and Herbert. There was no effect of soil on the yield of the tested cultivars.

In addition, the results of winterkilling in 1972 are presented. The biggest winter injury of the investigated highbush blueberries was recorded from plants grown on the substrate No 1. Among the cultivars, Darrow and Blueray had the highest percentage of winterkilling, if compared to the total terminal growth. Whereas in the case of the number of winterkilled terminals, Darrow, Herbert, and Lateblue were affected.