MODIFIED BRUNNER-SPINDLE AS A TRAINING SYSTEM FOR SEMI-INTENSIVE SWEET CHERRY ORCHARDS

Dwarf cherry trees are inevitable for intensive orchards and hand picking. The Brunner-spindle training system was developed for sweet cherry trees, but scarcely used in practice. In order to save space in our rootstock trial at the Department of Pomology, Budapest we intended to apply the Brunner's spindle-training system. During the first 5–7 years it turned out that the original method resulted in some disadvantages. That is why we had to modify certain elements of the training system.

Modifications were made in the following elements:

1. Delayed heading and pinching upright shoots around the terminal one.
2. Brunner's sectorial double pruning is used only in the early years in limited extent.
3. The strong upright shoots on the flat branches should be pinched or pruned back.
4. Zahn's method of using a stump or a longer stub as a form of corrective pruning is used for the removal of large branches.

Modified Brunner-spindle trees are developed with a central leader and wide-angled branches on it. Light bearing wood is positioned on the central leader and wide-angled branches. During training, shoots for branches are bent or a sectorial double pruning is used. The growth of central leader is reduced by delayed heading, and the strong upright shoots are pinched in summer. Based upon tree size spacing of 5 to 6 m between row and 3 to 4 m between tree appears appropriate. This training system is useful for handpicking and it is suitable for mechanical harvesting as well.

Modified Brunner-spindle is suitable for either strong or medium-strong or semi-dwarf rootstocks. However, when defining the spacing, the rootstock's effect on growth should be taken into account. One-year-old trees with or without laterals can be used. Laterals with narrow-crotch-angles should be bent so that sectorial double pruning can be used. For trees without laterals the above procedure should be carried out on the growing shoots. Delayed heading, Brunner's sectorial double-pruning and pinching reduce considerably labour requirements for training operations.