Olives in Istria Region: Autochthonous varieties in Slovenia

Istria Region: Croatia and Slovenia countries
Olive (Olea europaea L.) is one of the oldest cultivated plants characteristic of the Mediterranean area, where it is the most important oil-producing crop. The first historical records of olive growing in the Istrian region date from the first century BC. Istria is the largest Adriatic peninsula located in the north-west of the Adriatic Sea, with area shared by three countries: Croatia, Slovenia, and Italy. Surrounded by the sea from three sides and with northern border towards the continent, it has always been the natural link between Central Europe and the Mediterranean. Its favourable geographic position and Mediterranean climate have encouraged its long olive growing tradition and this area marks the northeastern limit of olive growing.
According to the latest official statistical data, a total of 600,000 olive trees are cultivated in Croatian Istria  and 300,000 olive trees on 1200 ha in
Slovenia (estimation).
Although in
Croatia, introduced, mostly Italian varieties predominate in new plantations, old autochthonous varieties have recently increased in importance due to their adaptation to local conditions, oil quality and consumers’ preference for typical olive oils with a specific origin. Preliminary surveys based on morphological data of olives showed the presence of various local olive varieties in old plantations in this area. Old local varieties exhibit significant biological variability, but knowledge about their origin, selection and level of molecular variability is still limited.

Typical olive trees in Croatia (Foto: P. Alonso)

In Slovenia, variety “Ernica” was the most frequente olive variety growing (60-70%of all trees), in Ankaran peninsula at the end of the 19th century. Due to the better yielding properties, growers decided to graft old varieties with “Istrska belgica” brought brom Boljunc near Trieste and Osp. In 1956, the following varietal structure was recorded in Slovenia Istria: “Ernica” (41,5%). “Istrska belica” (28,3%), “Drobnica” (12,5%), “Buga” (9,4%) and other varieties (8,3%)such as “Boiese”, “Storta”, “Lecino”, “Toscana”, “Frantoio”, “Mata, “Greca” (syn. Grossa do Spagna), “Smartella”, “Samec”, “Misnica” and “Dalamatinka” (Leskovec, 1956). After the big frost in 1956, this structure changed in favour of “Istrska belica”, due to the grafting of old varieties “Drobnica” and “Ernica”.
Import of seedlings from Italy had also influence on shaping the modern varietal map, because some of the best with better quality were included since 1985. With the younger olive orchards of “Leccino” and “Pendolino can be found beside the “Istrska belica”.