Euphorbia guyoniana ethanolic extract efficiency against tomato leaf miner in southeastern Algeria

Abstract

The abusive use of insecticide on tomato crop may cause several impacts to environment and human aswell as they can provoke resistance to plants. For that reason, a biological alternative was tested by using the ethanolic extract ofEuphorbia guyoniana, spontaneous plant collected from arid regions in Southeastern Algeria, against eggs and larvae of tomato leaf minerTuta absoluta Meyrick (Lepidoptera: Gelechiidae). Materials and Methods: The 120 tomato leaf miner larvae T. absoluta of the L2-L3stages and eggs were tested into contact with E. guyoniana ethanolic extract within 3 doses chosen after several preliminary tests:20, 30 and 40 μg. Results: Experimentation showed the larvicidal effect of this plant varied with doses and time. The greatest mortalitywas obtained by the D3 (40 μg) with 50.83±19.54 and 95.42±03.15% noted after 2 and 96 h, respectively. The DL50 recorded was between22.69 and 19.49 μg/larva, involving 50% of mortality. The treatment of eggs showed mortality rates of 15±05, 35±05 (D 30 μg) and95±05% (D 40 μg) at the end of the test. Conclusion: The ethanolic extract of E. guyoniana revealed that it could constitute a good meansof managing T. absoluta that might be introduced in sustainable organic agriculture