Inflorescence Traits and Floral Quality Parameters in Promising Olive Clones (cv Leccino): Influence of the Canopy Position

Abstract

In olive (Olea europaea L.), the floral quality is a key feature affecting the final fruit crop. The aim of this study was to evaluate the inflorescence traits and the floral quality parameters of three clones of Leccino cultivar (L 1.3, L 1.4, L 1.9). To assess a possible effect of light limitations on these parameters two canopy zones, internal (IZ) and external (EZ), were considered. The inflorescences were collected over two consecutive years in order to establish: (i) the characteristics of inflorescences (length, flowers per inflorescence) and flowers (open and perfect flowers); (ii) the ovary structure by histological analysis; and (iii) the viability and germination of pollen grains by in vitro culture. The preliminary results highlighted some differences among clones. The L 1.9 was the less affected by the canopy position for inflorescence morphological traits, and the presence of ovaries with at least three fully developed ovules denoting a high female fertility. Regardless of the canopy position, L 1.4 showed the highest pollen viability, suggesting its possible use as pollinator. The lower sensitivity of female and male floral organs to partial shading of L 1.9 and L 1.4 needs further investigations aimed at evaluating their suitability in high-density olive orchards.