**1. Introduction**

80 Olive Germplasm – The Olive Cultivation, Table Olive and Olive Oil Industry in Italy

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The Italian history of crop protection has been dominated by the use of agrochemical, generally having a negative impact on the environment and residues in final products. The approach based on the use of genotypes with low susceptibility to biotic stresses searching for sources of resistances was largely uninvestigated for long time. Only recently researchers focussed their studies on this subject. Studies devoted to this subject are very difficult mainly for permanent crop such as the olive tree because time consuming and because it is very hard to compare the behaviour of a large germplasm in the same pedoclimatic condition. Furthermore, it is very hard to design tests of resistances under controlled conditions because of the difficulty due to the hard tolerance of captivity of pests such as olive fly and many others. In any case, recently research activities on this field has been greatly improved and several research projects are supported by many institutions.

On the other hand, abiotic stresses has been sufficiently studied, mainly for those concerning the cold tolerance. The CRA-OLI of Rende studied from fifteen years the behaviour of several cultivars in respect to the main biotic stresses utilising two large varietal collections planted in two experimental fields, the largest on the ionian coast of Calabria (Mirto-Crosia, Cosenza) and the smallest near Rende (Cosenza). Results showed a high behavioural diversity of observed cultivars showing different degree of susceptibility to main pathogens and phytofagous of the olive tree. Some cultivars has been deeply investigated searching for the mechanisms determining such behavioural differences.
