The Role of Male Flowers and Bearing Status on Pollen Germination in Olive (Olea europaea L.)

Document Type : Original Article

Authors

1 Crop and Horticultural Research Department, West Azerbaijan Agricultural and Natural Resources Research Center, Agricultural Research, Education and Extension Organization (AREEO), Urmia, Iran

2 Plant Diseases Research Department, Iranian Research Institute of Plant Protection, Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran

Abstract

Olive is an andromonoecious plant producing both male and perfect flowers. This study was performed to determine the pollen germination percentage and growth rate of male and perfect flowers of Zard and Roghani cultivars in 2015 at the Tarom olive research station. Three trees from each cultivar (On and Off bearing) were selected. Pollen was collected from male and perfect flowers on the flowering shoots at flower opening stage. These anthers insert the capped glasses. Pollens were incubated in a modified medium that contained 0.8% agar, 10% sucrose, and 100-ppm boric acid. Pollens were spread using a modified medium, separately collected pollens of male and perfect flowers were spread on Petri dishes containing the medium, and then transferred into the incubator for germination at 25°C. After six hours of incubation, the number of germinated pollen grains was enumerated and recorded. The Zard olive cultivar had a higher pollen germination percentage (39.95%) than the Roghani olive cultivar (29.8%). In both cultivars, the male flowers exhibited a pollen germination rate of 48.01%, whereas the perfect flowers demonstrated a lower germination rate of 21.73%. Moreover, the germination rate of perfect flowers was significantly greater in the Zard cultivar (35.2%), in contrast to the Roghani cultivar (20.7%). In both cultivars, the pollen germination rate was 39.48% in the Off-season trees, surpassing the germination rate of 36.38% observed in the On-season trees. Moreover, the Zard cultivar exhibited a significantly higher germination rate of 41.13%, compared to a germination rate of 38.27% found in pollen from the Off-season of the Roghani cultivar. The overall results showed that male flowers of olive trees play an important role in the fertility and fruit set of perfect flowers.

Graphical Abstract

The Role of Male Flowers and Bearing Status on Pollen Germination in Olive (Olea europaea L.)

Highlights

  • Research reveals the role of male flowers in pollination and fruit set in Zard and Roghani olive cultivars.
  • Alternate bearing in olive cultivars affects pollen germination in both male and perfect flowers.
  • The pollen germination rates of the Zard olive cultivar are higher than those of the Roghani cultivar.
  • Male flowers of olive trees play a crucial role in the fertility of perfect flowers.

Keywords

Main Subjects

References

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Agrotechniques in Industrial Crops
Volume 5, Issue 2
Agrotechniques in Industrial Crops (Agrotech Ind Crops) (Online ISSN: 2783-2945)
June 2025
Pages 97-103

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