An assessment was made of the ovicidal activity of egg-parasitizing fungi Pochonia chlamydosporia (isolates VC1 and VC4) and Paecilomyces lilacinus on Toxocara canis eggs in vitro. The fungal isolates were inoculated onto Petri dishes...
moreAn assessment was made of the ovicidal activity of egg-parasitizing fungi Pochonia chlamydosporia (isolates VC1 and VC4) and Paecilomyces lilacinus on Toxocara canis eggs in vitro. The fungal isolates were inoculated onto Petri dishes with 2% water-agar (2% WA) and stored at 25 degrees C for 10 days in an incubator, in the dark. The control group was comprised of Petri dishes without fungi, containing the 2%WA medium only. Later, 1000 embryonated eggs were placed on the surface of the plates with fungal isolates and also on the control plates, and were then incubated at 25 degrees C for 7, 14 and 21 days. At these intervals, the eggs were retrieved and underwent percentage assessment according to the following parameters: no changes; type 1 effect, physiological and biochemical effect without morphological damage to eggshell, with visualization of hyphae adhered to eggshell; type 2 effect, lytic effect with morphological changes in embryo and eggshell, without hyphal penetration through the eggshell; type 3 effect, lytic effect with morphological changes in embryo and eggshell, with hyphal penetration and internal egg colonization. All the fungal isolates showed ovicidal activity (type 3 effect) on T. canis eggs, with 13.8%, 20.5% and 20.3% of ovicidal activity using P. chlamydosporia isolate VC1 after 7, 14 and 21 days, whereas isolate VC4 showed 15.2%, 19.0% and 21.7% of ovicidal activity at the same time intervals. P. lilacinus showed ovicidal activity of 12.3%, 18.8% and 20.0% after 7, 14 and 21 days. P. chlamydosporia and P. lilacinus were effective in vitro on T. canis eggs and can be considered a potential candidate to biological controller of those nematodes.