Three Releasing Doses of Trichogramma Sp. (Hymenoptera: Trichogrammatidae) with Bacillus Thuringiensis Kurstaki in Controlling of Batrachedra Amydraula Meyrick Eggs on Date Palm Trees

Abstract

The efficiency of two Trichogramma species Trichogramma brassicae and T. embryophagum in combination with bacterial suspension of Bacillus thuringiensis in controlling of the lesser date moth, Batrachedra amydraula Meyricke. Three release doses (50, 100 and 200 parasitoids/tree) for each species were examined in farm and the parasitism rate, adult’s emergence, the number of females and adult longevity of T. brassicae and T. embryophagum were studied. The results showed that both Trichogramma species were significantly efficient, especially at higher dose (200 parasitoids/tree), in their parasitism activity on B. amydraula eggs. However high reduction in infestation was achieved by B. thuringiensis with T. embryophagum (70.1%) at concentration of 10⁶ cell/ml B. thuringiensis. In addition, no significant differences was obtain between T. brassicae and T. embryophagum in mortality and adult emergence rates when they were treated with/without B. thuringiensis reared in the B. amydraula. However, the longevity of T. embryophagum was significantly more than T. brassicae. This is the first study to investigate T. embryophagum for parasitizing the eggs of B. amydraula and results of present study suggested that T. embryophagum with B. thuringiensis could be more effect for biocontrol of B. amydraula.