Efficiency of some medicinal plant extracts and an entomopathogenic fungus, Metarhizium anisopliae separately and in combination with proteus® against the large cabbage butterfly, pieris brassicae L.

Pieris brassicae (Lepidoptera: Pieridae) causes great qualitative and quantitative damage to cabbage crops. The present research was conducted to assess the synergistic/antagonistic interactions of Satureja hortensis , Trachyspermum ammi , Ziziphora tenuior , Cuminum cyminum , and Foeniculum vulgare methanolic extracts with Metarhizium anisopliae and Proteus® against P. brassicae pupae under laboratory conditions. The tested methanolic extracts when combined with M. anisopliae and Proteus® possessed synergistic efficacy (except for M. anisopliae + ammi). Probit analysis of extracts revealed S. hortensis as the most effective extract with LC 50 value equivalent to 43.49 ppm. Proteus® also exhibited a high efficacy (LC 50 =48.88). The results support the potential of cumin, fennel, savory and ziziphora methanolic extracts to improve the efficacy of M. anisopliae . Results demonstrated that all tested extracts integrated with Proteus® provide more effective control of P. brassicae than Proteus® alone.