Résumé:
As part of a natural resources development, it seemed interesting to study the insecticidal
and antifungal action of the essential oils of two aromatic plants Thymus sp. and Origanum sp.
pushing to the spontaneous state in Algeria. The present study aims to propose alternative
solutions based on the use of natural products to fight against the white grub.
The main objective of our work is to verify the effectiveness "in vitro" of the essential
oils of Thymus sp. and Origanum sp. on whiteworm larvae and at the same time test their effect
on entomopathogenic fungi Beauveria sp. and Fusarium sp ..
The results of the first part show that whiteworm larvae are highly sensitive to the effect of
Thymus sp. in comparison with that of Origanum sp..The use of thyme to control this pest
allowed to observe mortality rates greater than 92% at the 5th day at a dose of 0.031%; while for
individuals exposed to the effect of oregano HE less than 61% of the larval population was
eliminated on the same day and at the same dose.
The analysis of the results of the antifungal activity of the HEs of the two aromatic plants with
respect to the entomopathogens Beauveria sp.et Fusarium sp. show that the HE of Thymus sp.
has a lower inhibitory capacity for mycelial growth than Origanum for both strains of
entomopathogens tested.
