4.3.4. Experiment III: Interaction between Olive Cultivars and Treatments

To evaluate the influence of the interaction between olive cultivars and treatments on the effect of OSE on *V. dahliae*, olive plants of the three cvs. described above were treated with two BCAs (fungus *Aureobasidium pullulans* strain AP08 and bacterium *Bacillus amyloliquefaciens* strain PAB-24) and two commercial products [copper phosphite (Phoscuprico®) and potassium phosphite (Naturfos®)] (Table 4). These treatments were selected for this experiment for their efficacy in inhibiting conidial germination of *V. dahliae* in *Experiment II*.

Plants were treated 6-, 5-, and 3 weeks before obtaining the OSE and inoculated 4 weeks before obtaining the OSE. The treatments, OSE extraction, and plant inoculation were conducted as described above. For each olive cultivar, a positive and a negative control were included, as described in *Experiment II*. A randomized complete block design with three blocks and four replicated olive plants per treatment (*n* = 6, four treatments and two controls) and cultivar (*n* = 3) combination was used (72 plants per olive cultivar; 216 plants in total).


**Table 4.**

Biological and chemical products evaluated in this study a.

non-evaluated

 products and dose combinations

 in this study.

This experiment was maintained for six weeks after the first treatment was applied. Subsequently, OSE was obtained from plants of each treatment and olive cultivar combination, as well as from plants of the positive and negative control, joining all the plants of each block, so there were three experimental units of OSE (≈20 mL) per treatment or control and cultivar combination.
