Wherever a control measure is deemed necessary, a biological, physical or biotechnical control method must be used if available and effective e.g.
Bactrocera oleae (olive fruit fly)
- Bait sprays: With this method, the quantity of sprayed insecticide is greatly reduced ‘spot spaying’ (in comparison to cover sprays as well as the damage to beneficial and other fauna. These sprays should start at the beginning of fruit kernel hardening, taking into account several other criteria such as trap catches (based on an effective monitoring system), temperature, wind speed and relative humidity data, the % of fertile females in the population and local experience. Effectiveness of the method depends also on careful and early monitoring to determine the hot spot areas in the region (i.e. favorable for olive fruit fly microclimate, trees with unharvested fruits, susceptible varieties, irrigated or abandoned farms that may act as sources of the pest).
- Lure & kill techniques: Food and sex attractant traps impregnated with insecticides McPhail or bottle types of traps baited with food attractant represent environmentally safer methods for olive fly control. A dense net of bait traps with or without sex pheromone (mass trapping) can be established in late spring or early summer before the commencement of fly oviposition, and further extended in September, if needed. After establishment, close monitoring with bait traps and fruit sampling should follow. Bait sprays should be applied in cases of high fly populations as indicated in McPhail captures or fruit infestations.
- Biological control: Natural enemies such as larval and pupal parasitoids or epigeal predators and fungi may be active but generally they do not suppress the pest below economically significant levels. Suitable cover crops may support the regulatory effect of natural enemies
- Cover sprays: Reliance on cover sprays would require frequent applications that may have a detrimental impact on the beneficial and other fauna and may contribute to the appearance of new infestations of secondary pests and development of resistance. Cover sprays can be applied based on economic thresholds depending on the variety and region, generally lower for table and higher for olive oil varieties. Cover sprays only to be applied in specific cases of high infestations.
Prays oleae (olive moth)
- Damage to young fruit can be serious in certain regions and varieties (depending also on plant/canopy management). Monitoring of the moth population by sex pheromone traps always combined with flower or fruit infestation monitoring is essential.
- Several natural enemies are active against this pest and should be protected. Sprayings against anthophagous larvae are only applied in cases of low percentage of olive flowering and high population density of the pest. In these cases Bacillus thuringiensis can be used.
- Treatments with compatible selective insecticides should be applied to prevent the entry of hatched larvae in young fruit.
Saissetia oleae and other scales (Parlatoria oleae, Aspidiotus nerii etc.)
- Can be efficiently controlled by beneficial fauna.
- Cultural methods such as pruning and moderate use of nitrogen fertilizers are is of major importance
- Monitoring is based on sampling to estimate the population density as well as the % of parasitism and the presence of honeydew or sooty mould.
In case of outbreaks selective insecticides have to be applied during the hatching period.