Cercospora apii
Fressen causes early blight of celery in warm areas of Venezuela. To study its control, the effect of ethanolic extract (EE) of ‘albahaca genovesa’ was evaluated on the fungus and the disease. Plants used for EE preparation were grown in the field, its leaves were let dry, grinded and macerated in 96 % ethanol for 48 h; the crude extract was obtained by distillation in a rotoevaporator Brinkmann
MR and was stored until biological tests were performed.
In vitro test was conducted with EE at 1; 1,5; 2; 2,5; 3 y 4 % concentrations, evaluating the fungus mycelial growth inhibition (ICM), using a complete random design with 4 replicates. In the
in vivo test, celery plants, variety Utah 52/70 were inoculated with a suspension of 8 x 10
4 conidia/mL of
C. apii; the EE was applied weekly at 5, 10, 15 y 20% concentration, a control plant was included inoculated and without EE application. A complete random design with 10 replicates was used, and evaluation included incidence and disease severity, the latter one was used to calculate the percentage of disease reduction (RE). Results from the
in vitro test indicated that 4% of EE was statistically more effective with100% of ICM reduction. With regard to the
in vivo test, it was found that EE at 20% showed the highest RE (100%) at 14 days. Results of the research indicate that leaf extract from this plant might be an alternative to control celery early blight.
