Agriculture Reference
In-Depth Information
shallow root systems limit the use of cultivation under the tree. A translocated
herbicide may be needed for perennial weeds and is applied as a spot spray.
HARVESTING AND POSTHARVEST HANDLING
Harvesting season, yield and harvesting
The harvesting season is quite similar in most areas, dif ering only in range
(Table 6.8). Sweetsop is usually harvested during the summer months,
from July to November, and can be extended to March (Fig. 6.7). Atemoya is
harvested in autumn in the southern hemisphere and winter in Australia (Fig.
6.7) and from October to January in Poona, India.
A major problem in
Annona
cultivation is obtaining commercial yields. In
order to increase yield, hand-pollination (Fig. 6.4) has become an important
aspect of cultivation practices in some areas, especially for atemoya. Use of
pollen stored under poor conditions, naturally defective pollen and pollinating
during the hottest period of the day result in very poor fruit set.
Rootstocks have been shown to greatly infl uence yield (Sanewski, 1991).
Trees of the same age and cultivar on cherimoya rootstock yield almost double
that of trees grafted on sweetsop. Cultivar dif erences in yield have also been
noted (Fig. 6.8). Estimated yield per tree of 6-year-old 'African Pride' on
cherimoya rootstock is about 90 kg, while that of 'Pink's Mammoth' of the
same age and on the same rootstock is about 30 kg. In other cases yields of
80-150 kg/tree
are recorded for cherimoya and sweetsop, equivalent to 15-25
t/ha.
Fruit is harvested when fully mature and fi rm. The skin colour changes
as the fruit approaches maturity. Skin of immature cherimoya and sweetsop
is greyish-green but turns to yellow-green at maturity. In the latter fruit,
Table 6.8.
Peak harvesting seasons for some
Annona
species.
Countries
Cherimoya
Atemoya
Sweetsop
Australia
Mar.-Sept.
Argentina
Feb.-July
California
Mar.-Apr.
Caribbean
June-Sept.
Chile
Aug.-Dec.
Florida
July-Oct.
July-Sept.
July-Sept.
Hawaii
Aug.-Nov.
India (Poona)
Nov.-Feb.
Oct.-Jan.
Aug.-Nov.
Portugal (Madeira)
Nov.-Feb.
