The Efficacy of Melatonin on Flower Characteristics and Fruit Formation in Some Olive Cultivars Exposed to Low Irrigation

Document Type : Original Article


1 Crop and Horticultural Science Research Department, Kermanshah Agricultural and Natural Resources Research and Education Center, AREEO, Kermanshah, Iran

2 Department of Horticultural Science, College of Agriculture, Shahid Chamran University of Ahwaz, Ahwaz, Iran

3 Department of Horticultural Science, Faculty of Agriculture, University of Maragheh, Maragheh, Iran

4 Department of Plant Protection, Faculty of Agriculture, University of Kurdistan, Kurdistan, Iran

5 Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania Luigi Vanvitelli, Caserta, Italy



The purpose of this study was to address the influence of melatonin foliar application on the flowering and fruit formation of olive cultivars of Sevillana and Roughani at the Dalaho Olive Research Station conditions of Kermanshah province. The experiment was conducted in a randomized complete block design in a factorial arrangement and three factors (MEL concentration, irrigation regime and olive cultivar) with 3 replicates and implemented in the crop year 2021-2022. The trees were sprayed with melatonin [0 (as a control), 50 and 100 µM] before flowering and during rapid fruit growth (two growth stages) on leaves. Irrigation treatments included 100% (control), 75 and 50% evapotranspiration. In order to investigate the state of flowering and fruit formation of olive cultivars under drought stress and melatonin foliar application, flower and fruit formation were recorded. Statistical analysis of variance and comparison of averages was done by Duncan for multiple comparisons between pairs of treatment as a post-hoc test. The results showed that flower traits and fruit formation were significant under the impact of variety, various levels of melatonin and irrigation regime at the probability level of 1%. The decrease in the amount of irrigation water affected flower characteristics and fruit formation. Melatonin foliar spraying improved the condition of flowering and fruit formation in Sevillana and Roughani cultivars.

Graphical Abstract

The Efficacy of Melatonin on Flower Characteristics and Fruit Formation in Some Olive Cultivars Exposed to Low Irrigation


  • The studied olive cultivars had different reactions to MEL and irrigation treatments.
  • The flowering status of olive cultivars was highly affected by drought stress.
  • Drought-negative effects were mitigated in cultivars treated with MEL.


Main Subjects

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