Comparison of 18 rootstocks for apple tree cv. "Elise" in V planting system

The experiment was set up on a fertile alluvial soil, at the Warsaw-Wilanów Experimental Station, Central Poland, in spring of 2000. Apple trees of cv. ‘Elise’ were planted on 18 rootstocks of different origin and grew in “V” planting system. Different rootstocks were classified into three groups, depending on expected tree vigour: semi-dwarfing (P 14, P 60, B.396 and M.26), dwarfing (B.9, B.146, P 2, P 59 and seven subclones of M.9 – EMLA, Burgmer 984 & 751, T339, Pajam 1, Pajam 2, RN29) and superdwarfing (M.27, P 16, PB-4). Trees on rootstocks assumed as semi-dwarfing were spaced at a distance of 3.8 × 1.0 m, on dwarfing – at a distance of 3.5 × 0.7 m and on superdwarfing – at a distance of 3.2 × 0.5 m. The trunk cross-sectional area (TCSA) after 6 years on semi-dwarfing rootstocks was the greatest on P 14; vigour of trees on other rootstocks was similar. The cumulative yield per tree (2001-2005) was the lowest on M.26. Fruit size did not depend on the rootstock. The cropping efficiency coefficient (CEC) was the highest of trees on B.396 and the lowest – on P 14. On rootstocks considered as dwarfing, TCSA after six years was the smallest on P 59 and the largest on M.9 EMLA; vigour of trees on other subclones of M.9 was smaller and similar. The lowest cumulative yield per tree was obtained on P 59 and the highest – on M.9 751, M.9 984 and M.9 EMLA. Fruit size was similar and did not depend on rootstock. The CEC was the highest on P 59. On superdwarfing rootstock trees on PB... [to full text]