Tree shaping strategies for higher density mango orchards.
Stassen P. J. C., Grové H. G., Davie S. J.
Author Affiliation: Institute for Tropical and Subtropical Crops, Private Bag X11208, Nelspruit 1200, South Africa.
: 106-109
Abstract : This study examined different tree training systems for shaping trees to be more effective in higher density orchards when they have filled their allotted space. Open vase, closed vase, central leader, palmette and standard pruning systems were compared with unpruned controls. Postharvest pruning and pruning after fruit set was also evaluated with each of the tree training systems as measures to maintain tree size. Seven-year-old 'Sensation' and 6-year-old 'Tommy Atkins' mango trees that have been trained and pruned consecutively for 3 years (1995, 1996 and 1997) were used in the trial conducted in Nelspruit, South Africa. Results clearly showed that the 7×3 m spacing is too wide for 'Sensation' under prevailing conditions. Planting of trees at 5×2 m is therefore justified if a tree training and manipulation programme is in place for maintaining such an orchard from its third year. The informal pyramidal form (something between a central leader and a closed vase) appears to be ideal for achieving good light management, with a possible yield exceeding 30 t/ha after 7 years. In windy areas, the palmette system has certain benefits as the bearers are supported by wires but this is more expensive because of the trellis system. In the case of a late cultivar, such as 'Sensation', a system must be adopted where annually a percentage of the bearers can be hardened off in time for bearing fruits in the current season and the rest will be new bearers for the fruits of the following season. Rejuvenation pruning can be carried out on the bearing tree of 'Sensation' in October/November. An early cultivar such as 'Tommy Atkins' should be pruned immediately after harvest to an informal pyramidal shape to allow enough light into the canopy for good colour development on the fruit.