Productive and pomo-technical properties of fruits of plum cultivars grown under dense planting system

The studies were conducted at Fruit Research Institute, Čačak (Serbia) over 2007-2010. The trial included two plum cultivars, i. e. 'Čačanska Rodna' and 'Stanley'. The chosen cultivars were grown under dense planting system in five variants of treatment, i.e. I - 4.0 x 1.0 m (2,500 trees/ha); II - 4.0 x 1.5 m (1,666.6 trees/ha); III - 4.0 x 2.0 m (1,250 trees/ha); IV - 5.0 x 3.0 m (666.6 trees/ha) and V (control) - 5.0 x 4.0 m (500 trees/ha). The obtained results in 'Čačanska Rodna' did not vary significantly among treatments in respect of size and weight of fruit and stone, flesh ratio, stalk mass and length and soluble solids content. Difference was highly significant in yield per tree and unit land area, as well as in cumulative yields. The highest yield per tree and unit land area (4.59 kg and 11.5 t, respectively) as well as the highest cumulative yields (13.8 kg and 34.4 t, respectively) were recorded in the variant 4.0 x 1.0 m (2,500 trees/ha). Yield per tree and unit land area (2.76 kg and 1,48 t, respectively) and cumulative yields (5,9 kg and 2,96 t, respectively) were lowest in the control variant 5,0 x 4,0 m (500 trees/ha). In 'Stanley', major variation was observed in size of fruit and stone, flesh ratio, stalk mass and soluble solids content. Highly significant difference was recorded in fruit weight, yield per tree and unit land area as well as in cumulative yields. The highest yield per tree and unit land area, as well as the highest cumulative yields (8.04 kg, 7.56 t and 18.1 kg, 22.7 t, respectively) were observed at spacing 4.0 x 2.0 m (1,250 trees/ha), whereas these were the lowest (433 kg, 2.89 t and 13.0 kg, 8.66 t, respectively) at a spacing of 5,0 x 3,0 m (666,6 trees/ha).