Last summer many infected groves were destroyed by burning - that is a serious move!
The article linked to below provides more information -
and there are further articles around in the scientific press as well. There are links to other articles from this report in Scientific American online.
|Olives - Italy|
It is certainly very serious for world olive production, particularly in Europe and north Africa, although it may be beneficial to commercial producers in Australia, USA and Chile for example. Fruit is not affected, only the tree, and that reduces yield, often to nil. Some varieties seem to offer a degree of resistance or tolerance based on some studies in Italy, but that is not total immunity.
While removal by burning the infested olive groves has been the most common option, there are some questions being asked about alternatives. Substantial heavy pruning may offer some options to manage the bacterial disease. However, it does not appear that a reasonable overall solution has been developed.
Biosecurity issues require strict movement controls on trees and planting materials as well as measures to prevent host insect movement. Management of the groves to reduce or remove sites for the insect to live are also needed. This whole problem is likely to prove difficult, with growers and tourists being potential, maybe even unwitting, dispersal agents.
This is a very serious plant pest and will require a major effort to manage the problem, for many years to come, and there will be further developments, no doubt. Losses are already substantial, and likely to be worse before any improvement.