Performance of different vigour rootstocks in Latvia during eighteen years

In the largest part of fruit production regions apples grown on dwarf rootstocks and the canopy performed dominantly as slender spindle. In conditions of Latvia mainly semi-dwarf apple rootstocks are used. Planting distances between them allow performing pyramidal and wider canopy. The aim of the trial was to evaluate the suitability of some apple rootstocks for growing in Latvia and their compatibility with the cultivar ‘Auksis’. In two trials a combination of 8 dwarf and 4 semi-dwarf rootstocks with apple cultivar ‘Auksis’ were compared. The largest yield was obtained for the dwarf rootstocks M9 EMLA, M26 EMLA, B9 and semi-dwarf rootstocks MM106 and G30. The highest cumulative yield efficiency of 18-year-old trees was obtained for combinations with the rootstocks B9, B396. Yield efficiency on the semi-dwarf rootstock G30 was only a little smaller than on dwarf rootstocks. In the group of semi-dwarf rootstocks G30 offers most perspective taking into account yield efficiency at the beginning and a little larger yield per canopy volume later. The yields even after tree renewal continued increasing – the productive period of trees on the rootstock G30 may exceed twenty years.