Olive growing in arid area: further challenges from climate change

In Tunisia, agriculture is vulnerable to climate change with harmful impacts subsequent warming and drying trends. In these regions, olive industry plays a key role at regional and national level. Therefore, the identification of adapted olive tree genotypes has become an urgent need to develop sustainable agriculture in arid lands. This study aimed to evaluate the impact of climatic variation on the olive growing systems in arid and sub-arid areas of Tunisia. The phenological behavior of Chemlali and Zalmati, main olive cultivars wide spreading in central and southern Tunisia, respectively, were considered to evaluate their capacity to adapt to contrasting climatic conditions. Over the 2005-2019 period, olive cultivars presented variable flowering dates related to local climatic conditions. Zalmati cultivar bloom in Zarzis seems to be earlier than Chemlali cultivar in Sfax region with average flowering dates of DOY-92 (April-3) and DOY-106 (April-17), respectively. A tendency for advancing the growing season was observed with warmer winters, which leads to disruption of pollination, high risk of insect attack, and consequently harmful effects on the production and product quality. This investigation serves as a basis for making recommendations taking into account the production areas as well as for addressing projected climate change.