AUCTION - The Big Olive Processing Plant

Researchers Work to Reverse Genetic Erosion, Breed Resilient Olive Varieties

At the center of the global discussion around the link between sustainable development and climate change, biodiversity is generating more interest.

In terms of olive biodiversity, recent years have seen a growth of attention among operators in the agri-food sector and researchers, who are committed to counteracting genetic erosion, as well as to studying and breeding more resilient varieties.

“The olive tree (Olea europaea subsp. europaea) is a very ancient tree species with a great wealth of genetic diversity,” said Samanta Zelasco, a researcher at the Center for Olive, Fruit and Citrus Crops of the Council for Agricultural Research and Agricultural Economics Analysis Research (CREA-OFA) of Rende, in Calabria.

“First, we must clarify that ‘genetic diversity’ is the scientific definition that in the public debate is generally substituted by ‘biodiversity,’” she added.

According to the last official calculation carried out by CREA in 2012 on the United Nations Food and Agriculture Organization’s Second Report on the State of Plant Genetic Resources for Food and Agriculture, the olive germplasm present in the major ex situ collections in the world amounted to at least 2,629 different varieties.

Italy has the richest genetic diversity, with 734 denominations listed in the national register of fruit plant varieties, updated in 2020 by the Italian Agriculture Ministry.

“Italy boasts a very high number of varieties, and the composition of its olive germplasm is the largest and most varied in the world,” Zelasco said. “Being in the center of the Mediterranean, over millennia, the country has undergone several historical events and people movements that have favored the importation and exchange of plant material, contributing to enriching its varietal heritage.

Today, frequent reports of allegedly new genotypes indicate a great germplasm diversity. Yet, researchers warn that the precise number of varieties cannot be defined with certainty due to multiple cases of synonymy and homonymy.

We recently carried out an in-depth molecular investigation of the Italian varieties using a very large number of markers that cover almost the entire genome,” Zelasco said. We have not completed the study yet, but we can already say that presumably a good part of the genetic material, perhaps half, is represented by cases of synonymy.” 

The same probably happens in other countries,” she added. Still, Italy has a huge number of varieties, which are the result of local selections. In most Italian regions, we can find about 30 to 40 varieties, then a wide germplasm also at a local level.” More