Annona Species Monograph.pdf - Crops for the Future

Chapter 10. Agronomy
atemoya ‘African Pride’ on sugar apple rootstock and the widest spacing for
atemoya ‘Pink's Mammoth’ on cherimoya. In Brazil, soursop spacing varies
from 6 x 6 m to 8 x 8 m (Pinto and Silva, 1996), while sugar apple has a
wider range of spacing depending on the rootstock vigour, and varies from 6
x 4 m with sugar apple as a rootstock to 8 x 5 m with custard apple as a
rootstock (Kavati and Piza Jr., 1997).
10.3 Orchard management
Orchard management can be complex and there is a need to experiment to
ascertain the validity of many aspects. Innovation is also needed, e.g.
intensive cultural methods, such as trellising or espaliering, require study.
NRC (1989) reported that espaliering of cherimoya in Madeira (Portugal)
was extremely successful.
10.3.1 Windbreaks
Since most of the Annona species are shallow rooting and consequently very
susceptible to wind damage, the use of windbreaks is an important orchard
practice, particularly during the first three years (George et al., 1987). The
windbreak should be established prior to transplanting the annonas into the
field. Casuarina (Casuarina equisetifolia) has been used in some Brazilian
regions as a windbreak, although this species is very competitive for water
and is susceptible to natural combustion, thus offering a fire risk. The best
option is to consult the local extension service about windbreak species that
have proven useful locally, as well as their placement, which depends upon
their root distribution, plant height and crown density.
10.3.2 Pruning
Tustin (1997, cited by Castro et al., 1999) stated that pruning is an important
cultural practice used to regulate the tree canopy. It influences growth by
manipulating the balance between vegetative and fruiting growth (Cautin et
al., 1999). Current pruning methods in cherimoya produce shoots with
variable levels of vigour.
The literature mentions several types of pruning of annona trees, such as for
tree shape, maintenance, rejuvenation and production (also called green
pruning) (Torres and Sánchez, 1992; Agustín and Alviter, 1996; Pinto and
Ramos, 1997; Nakasone and Paull, 1998; Bonaventure, 1999). However,
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