Cancer is one of the most serious and dangerous disease of the olive tree. It is a moving bacteria that attacks every part of the olive tree. The infections of the branches are the most serious. Tumors appear individually or by groups, with round, green and smooth surface. As they grow in size, they crack and their masts get exposed, become black and hard, and a few cms in size, with irregularities.
When the leaves get attacked, they fall. The disease appear on the olives, in round spots, which in the beginning are dark and later become black with clefts.
The wounds of the pruning, the harvesting of the olives, the biting of the insects, the wounds of the hail and freezing, makes it easy for the bacteria to enter into the masts of the olive tree. With the mild weather temperatures, the high moisture and the vigorous germination of the olive tree, numerous clefts appear, favoring the penetration and the spreading of the bacteria.
All year round the bacteria exists on the surface of the leaves. In April, October and November, the population increases and attacks the olive tree, when it finds openings.
The spreading of the bacteria is done with the rain water and Dacos, which is the most dangerous insect of the olive tree.
The fighting of the disease is very costly, because it is impossible to stop wounds on the olive tree. Best results bring spraying with bacteria exterminating products.
The thready bacteria is another very dangerous bacteria. This bacteria , are very tiny warms, that attack the roots, and tumors appear. It destroys the masts of the roots, with results the weakening of the olive tree.
To fight this disease, the use of bacteria exterminating products is required, also the disinfection of the ground is needed, if the infection is serious.
Both diseases effects the quality of the production of the olive oil and the table olives.