Evaluation of three entomopathogenic nematode species against nymphs and adults of the sycamore lace bug, Corythucha ciliata

The sycamore lace bug Corythucha ciliata (Say) (Hemiptera: Tingidae) is an invasive species native to North America that has been introduced in Europe and infests various species of the ornamental plane trees (Platanus sp.). This study aims to test the susceptibility of C. ciliata nymphs and adults to different doses of three entomopathogenic nematode species under laboratory conditions. Heterorhabditis bacteriophora did not infect C. ciliata nymphs, while Steinernema carpocapsae exhibited higher virulence (77–96% at 132 IJs cm⁻²) to all stages of C. ciliata than S. feltiae (10–39% at 132 IJs cm⁻²). Steinernema carpocapsae was significantly more virulent at the highest dose (132 IJs cm⁻²) than at the medium (50 IJs cm⁻²) and lowest (25 IJs cm⁻²) doses. After 6 h and 12 h of nymph exposure to S. carpocapsae, this nematode caused 39% and 47% mortality at 132 IJs cm⁻², respectively. The virulence of S. carpocapsae was significantly lower at 15 °C than at 25 °C (75.5% and 96% adult mortality, respectively) but was still more virulent than S. feltiae at both temperatures (29.5% and 39% adult mortality, respectively). These results show that S. carpocapsae could constitute a viable biological control agent for C. ciliata.