Influence of nine dwarfing apple rootstocks on vigour and productivity of apple cultivar 'Granny Smith'

The influence of nine dwarf apple rootstocks (M.9 T 984, M.9 T 337, Jork 9, Mark 9, Budagowski 9, M.9 EMLA, Pajam 1, Pajam 2, and Supporter 4) on the vegetative characteristics, yield and yield efficiency, was evaluated on 'Granny Smith' apple variety (Malus domestica Borkh.). The experimental orchard was established in 2004, with a planting distance 3.5 m x 1.5 m, in Prespa region (Resen, R. Macedonia). The study has been performed during three consecutive years (2008-2010). The following characteristics were investigated: trunk cross section area, volume of the tree crown and tree crown area, leaf area, yield and yield efficiency. In general, it can be concluded that the effect of different rootstocks on most of the analyzed parameters was variable. The growth vigour of the trees grafted on Supporter 4, Jork 9, M.9 EMLA and Pajam 2 (Cepiland) was somewhat larger than the growth vigour of those on Mark 9, M.9 T 337, Pajam 1 (Lancep) and M.9 T 984. Trees grafted on Budagowski 9 have the lowest growth vigour. Rootstock Supporter 4 is semi-vigorous and the grafted trees had low yield efficiency compared to other evaluated rootstocks. The highest yield efficiency was observed at Pajam 1, Budagowski 9, M9 T 984 and Mark 9. The following rootstocks are recommended for growing in commercial plantations: M.9 EMLA and Pajam 2, as well as M9 T 337 and Pajam 1 for higher density orchards. (C) 2011 Elsevier B.V. All rights reserved.