Pollinizer' Effects on Olive Seed Set, Size and Abortion

Area of Science:

• Horticulture
• Plant Breeding
• Agronomy

Background:

• Olive (Olea europaea L.) is a self-incompatible species.
• Fruit development is typically characterized by one-seeded drupes.
• Variations in seeding patterns, including double-seeded and seedless fruits, can occur.

Purpose of the Study:

• To investigate the impact of different pollinizers on the seeding patterns of three self-incompatible olive cultivars.
• To analyze fruit and seed set, seed abortion, double seeding, and seed weight under various pollination treatments.
• To understand maternal and paternal effects on olive fruit and seed characteristics.

Main Methods:

• Evaluation of fruit and seed set, seed abortion, double seeding, and seed weight.
• Analysis of maternal effects across 'Arbosana', 'Koroneiki', and 'Sikitita' cultivars.
• Assessment of paternal effects through different pollination crosses.

Main Results:

• Significant maternal effects observed, with 'Sikitita' producing more double-seeded fruits and fewer empty endocarps than 'Arbosana' and 'Koroneiki'.
• Paternal effects were generally non-significant, but specific crosses showed marginal differences.
• 'Sikitita' pollen was highly effective in 'Koroneiki' and 'Arbosana', and 'Arbosana' pollen showed reciprocal success in 'Sikitita'.
• Twin seeds were frequently sired by different pollen donors within the same fruit.
• Fruit and seed mass positively correlated with viable seed number; fruits with aborted seeds were smaller, while double-seeded fruits were heavier.

Conclusions:

• Pollinizer choice significantly influences olive seeding patterns and fruit development.
• Cultivar-specific responses to pollination impact fruit characteristics and seed production.
• Seed number is a critical factor in determining overall fruit weight and quality.