Agriculture Reference
In-Depth Information
(a)
(b)
(c)
(d)
Fig. 4.6.
To protect the trees and fruit, various approaches can be used to reduce
the insect pest levels by use of traps (a), which may include a lure or sticky traps
in the nursery (b) and in the orchard on the trunk (c), and protecting the fruit by
bagging (d).
Cultural practices can be used, such as ploughing or discing to kill insects
present in the soil, weed control to remove shelter and an alternative place
to reproduce, and pruning damaged parts and burning them. In the case of
fruit fl ies, all fallen fruit should be buried at least 40-50 cm deep so that if
the larvae evolve into pupae there will be no chance for the fl ies to reach the
surface. High-pressure water sprays can also be used for control, and in other
cases, hand collection of the leaves with larvae that have hatched from eggs or
of larvae shaken from the plants.
Biological control includes the use of predators' parasites as well as
bacterial and fungal enemies. In many cases insect damage can be solved
by releasing predators or parasites that can be acquired commercially and
released in the orchard. This approach provides a very ef ective long-term
biological control. Examples include the ef ective control of many scales and
aphid insects in dif erent parts of the world. The bacterium
Bacillus thuringensis
is used widely to control many leaf-eating larvae and the fungus
Beauveria
to
control a number of pests such as whitefl y and dif erent beetles.
