Spilocaea oleagina (syn. Cycloconium oleaginum, Venturia oleagina)

Olive peackock spot disease is one of the most common and important foliar disease of olives worldwide and mainly in the Mediterranean area. Other common names are leaf spot of olive, olive scab, pecan scab, bird’s eyespot. Pathogens spores are dispersed through rain-splash and wind (water is necessary for the dispersion). Wet, humid environmental conditions favor the infection (optimum temperature 03-22oC and high relative humidity). In warmer areas, the optimum conditions may occur in autumn and mild winter. In northern climates, spring and even summer favor such conditions. Deferent olive varieties show deferent sensitivity in the pathogen.

Leaves: Most common and obvious symptoms occur in foliar. In the beginning, symptoms may take the form of brown or deep purple spots with unclear margin and smoky appearance on the upper leaf surface. The spots then become bigger and surrounded by a chlorotic halo and may cover the entire leaf surface. The spots are so-called peacock spots because of their similarity with the typical eyespot of peacock’s feather. Affected leaves turn yellow and fall prematurely. Severe disease outcome is the infection of a significant foliar percentage, leading to defoliation and compromised plant vigor.

Stem: Long, grey-brown lesions appeared on petioles, peduncles and pedicels.

Fruits: Drupes’ shrinkage and fall and eventually, significant crop losses.

Flowers: Blossom drop

Hosts: Olive tree

Panagopoulos G.C. 2007. Diseases of fruit trees and vineyards. Stamoulis Press.