Management of leaf curl plum aphid, Brachycaudus helichrysi (Hemiptera: Aphididae) by entomopathogenic nematodes

Abstract: The aim of this study was to determine the biological control effect of entomopathogenic nematode species, Steinernema carpocapsae, Steinernema feltiae and Heterorhabditis bacteriophora against the adult stage of LCPA (Leaf curl plum aphid). Experiments were evaluated under laboratory conditions. The tests were conducted in 10 cm Petri dishes lined with a moistened filter paper. One infested plum leaf containing 100-120 LCPA adults was placed in each Petri dish and the nematodes were applied as 50, 100 or 150 infective juveniles (IJs)/ml per cm2. Plates were incubated at 15, 20 and 25 °C and the insect mortality was checked 24, 48, 72 and 96 hours after the treatment. Ten Petri dishes were used for each nematode concentration and temperature. The results showed that entomopathogenic nematodes were quite effective against LCPA and the mortality was related to nematode concentration and temperature. At 15 °C, S. carpocapsae, S. feltiae and H. bacteriophora exhibited 59, 24 and 23% mortality, respectively. S. carpocapsae showed the highest mortality (79%) following S. feltiae (58%) and H. bacteriophora (32%). For all nematode species, the highest virulence was observed 85%, 69% and 58% on the temperature 25 °C and 150 IJs/ml cm2 concentration for S. carpocapsae, S. feltiae and H. bacteriophora, respectively. It was determined that LCPA can be controlled by S. carpocapsae, but further studies should be conducted under greenhouse and field conditions.