Annona Species Monograph.pdf - Crops for the Future

Chapter 10. Agronomy
methods (whip and veneer) to propagate soursop on several rootstocks
(commercial soursop, a local soursop type called Chocó soursop, custard
apple, and sugar apple). The shield-budding method on both soursops as
rootstocks showed the highest percentage take, with 83% of success. The
graft or bud union should be placed 15-20 cm above ground level (Pinto and
Silva, 1994; Nakasone and Paull, 1998) to avoid long trunks and tall
canopies.
Both budding and grafting are better carried out in spring with the start of sap
flow (Wester, 1912; Campbell and Phillips, 1983). According to George and
Nissen (1986), in the Philippines patch budding of sugar apple is
recommended prior to leaf abscission, which occurs during the dry season
(November to February).
Occasionally an annona grower may establish an orchard with an
unproductive or unpopular cultivar, whose negative results will only show up
three years later. He can replace the undesired canopy by using top working
methods (George and Nissen, 1987), essentially establishing a new
productive orchard with a high quality cultivar without replanting (Fig. 10-6).
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