The article is devoted to the research of the effect of tree pruning practices and terms on a diameter, a volume, an area of a crown projection and a level of using a nutrition area by fruiting apple trees, cv. Gala (Mitchgla), Golden Delicious (clone B) and Johnagold (Vilmutа) in the irrigated orchard on rootstock M.9 T337.
It has been found out that the change of crown parameters, first of all, depends on pruning practice and term. Optimal correlation of the processes of growth and fruit-bearing – the keystone of high orchard productivity – depends on crown dimensions.
In present-day intensive horticulture small-size crowns in densely planted orchards are formed by pruning in the areas determined by a planting scheme. Due to the increase of the level of labor remuneration and labor force deficit, mechanized handling of the orchards becomes urgent, in particular machine (contour) pruning of a crown. Considerably limiting fruit tree dimensions, contour pruning becomes one of the most efficient techniques in the optimization of fruit tree growth and productivity.
First winter contour pruning of all variants was performed according to a pattern: 80 cm in a lower part and 50 cm in an upper part of a crown, further new growths in a periphery were shortened annually. Hand work was done in the areas between trees, removing drooping, old and very thick branches.
When mechanized contour pruning is done (hand work between trees), a crown diameter is smaller by 12%, and when pruning is done after harvest – by 21%; as compared with winter pruning, a crown diameter is smaller by 39%, and when pruning is done after harvest – by 25%. A crown projection of cultivars Gala and Golden Delicious is smaller by 8-15%, as compared with cultivar Johnagold. The area of a crown projection is smaller by 35% after contour pruning (by 14% after harvest); the use of a nutrition area is smaller by 35% and by 14% when pruning is done after harvest. Pruning practice has a serious effect on the change of a crown volume (factor effect is 68%), the area of a crown projection (73%) and the level of using a nutrition area (73%).
apple tree, habit, projection area of a crown, contour pruning, pruning term