Long-term evaluation of super-dwarf rootstock: impact on tree growth, productivity and apple fruit quality
Impact of planting distances on apple tree growth, yield parameters and internal fruit quality was evaluated in a 14- to 17-year-old orchard planted on super-dwarf P.22 rootstock. Trial was performed at the Institute of Horticulture Lithuanian Research Centre for Agriculture and Forestry in 2014-2017. 'Auksis' apple trees were planted at the distances 3×1, 3×0.75, 3×0.50, and 3×0.25 m. The strongest growth, the highest number and total length of shoots, the highest amount of flower clusters and yield tree‑1 was recorded at planting distances 3×1 and 3×0.75. The growth and yield tree‑1 of very densely planted apples (3×0.25) was significantly lower, in spite of these trees being the most productive and giving the highest yield area‑1. The average fruit weight, diameter and colour were the best at planting distances 3×1 and 3×0.75. Fruit quality parameters significantly decreased in the super dense orchard. Long-term evaluation of apple trees on super-dwarf P.22 rootstock revealed that planting distance 3×0.75 guarantee annual yields of high quality fruits even in a 14- to 17-year-old intensive orchard. In the case of orchard replacement after 10-12 years the optimal planting distance of apple trees on P.22 rootstock is 3×0.5 in order to get the highest yield in the young age.
Uselis, N., Lanauskas, J., Vi'kelis, J., Liaudanskas, M., Samuolienė, G. and Kviklys, D. (2020). Long-term evaluation of super-dwarf rootstock: impact on tree growth, productivity and apple fruit quality. Acta Hortic. 1281, 185-190
vegetative growth, yield, Malus × domestica, planting distance, flowering