Developing Predictive Models under Controlled Conditions for the Selection of New Genotypes That Are Less Susceptible to Bactrocera oleae (Rossi) in Table Olive (Olea europaea L.) Breeding Programs
Bactrocera oleae (Rossi), the olive fly, represent an important biotic factor in olive groves
(Olea europaea L.) causing significant production losses. Ensuring effective management of this pest is
of paramount importance to safeguard and uphold the quality and quantity of table olive production.
The University of Seville’s (US) table olive breeding program has focused its attention on finding
new cultivars that exhibit reduced susceptibility to the olive fly. This study attempted to develop
predictive models to enable the selection of new genotypes that are less susceptible to the olive fly
based on fresh fruit traits. An extensive analysis of fruit physical (weight, size, symmetry, color,
and texture) and chemical traits (moisture, oil content, and phenolic compounds) was conducted
to evaluate the fly’s preference in oviposition bioassays (multiple choice and no choice) among
four genotypes (US-06-1388, US-06-194, ‘Hojiblanca’, and ‘Kalamon’), under controlled conditions.
The oviposition bioassays revealed the higher susceptibility of genotype US-06-194 and the lower
susceptibility of ‘Kalamon’. The predictive models incorporated physical traits such as, fruit weight,
longitudinal diameter, symmetry, CIELAB color attributes (L*, a*, and b*), and compression hardness,
as well as chemical traits such as moisture, and the contents of demethyloleuropein, oleuropein, rutin,
and verbascoside. These traits consistently predicted the preference of B. oleae for certain fruits.
The authors would like to acknowledge the technical support received from
Felipe Ignacio Rojas, Jose Manuel Rodríguez, Luis Felipe Pérez. We also thank the Foundation for
Science and Technology (FCT, Portugal) for their financial support to CIMO (UIDB/00690/2020) and
SusTEC (LA/P/0007/2020) through national funds FCT/MCTES.
