Page 24 - Climate Conference - EBook 2023: Al-Qasemi Academy

The effect of high temperatures on olive oil
yield and quality
Dr. Giora Ben Ari

Institute of Plant Sciences, ARO, Volcani Center

ABSTRACT
Global warming is predicted to have a negative effect on plant growth due to the
damaging effect of high temperatures. To address the effect of high-temperature
environments on olive oil yield and quality, we compared its effect on the fruit
development of five olive cultivars in a region noted for its high summer temperatures
with trees of the same cultivars in a region of relatively mild summers. We found that the
effects of a high-temperature environment are genotype-dependent. High temperatures
during fruit development generally affected three important traits: fruit weight, oil
concentration, and quality. None of the tested cultivars exhibited complete heat stress
tolerance. The final dry fruit weight at harvest of the 'Barnea' cultivar was not affected by
the high-temperature environment, whereas the 'Koroneiki,' 'Coratina,' 'Souri' and
'Picholine' cultivars exhibited decreased dry fruit weight at harvest in response to higher
temperatures by 0.2, 1, 0.4 and 0.2 g respectively. The pattern of final oil concentration
was also cultivar dependent, with 'Barnea,' 'Coratina,' and 'Picholine' not being affected by
the high-temperature environment, whereas the 'Koroneiki' and 'Souri' cultivars showed a
decreased dry fruit oil concentration at harvest under the same conditions by 15 and 8%
respectively.
Regarding the quality of oil produced, the 'Souri' cultivar proved more tolerant to a
high-temperature environment than any other cultivars analyzed in this study. These
results suggest that different olive cultivars have developed a variety of mechanisms for
dealing with high temperatures. Elucidation of the mechanism of each of these
responses may open the way to developing a variety of olives broadly adapted to
conditions of high temperatures.

Keywords: Climate change; Olive oil
Biography: • Nissim Y, Shloberg M, Biton I, Many Y, Doron-Faigenboim A, Zemach H,
Hovav R, Kerem Z, Avidan B, Ben-Ari G. (2020). High-temperature environment reduces
olive oil yield and quality. PLoS One 15(4):e0231956:
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0231956