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

The sycamore lace bugCorythucha 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 (Platanussp.). This study aims to test the susceptibility ofC. ciliatanymphs and adults to different doses of three entomopathogenic nematode species under laboratory conditions.Heterorhabditis bacteriophoradid not infectC. ciliatanymphs, whileSteinernema carpocapsaeexhibited higher virulence (77-96% at 132 IJs cm(-2)) to all stages ofC. ciliatathanS. feltiae(10-39% at 132 IJs cm(-2)).Steinernema carpocapsaewas 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 toS. carpocapsae, this nematode caused 39% and 47% mortality at 132 IJs cm(-2), respectively. The virulence ofS. carpocapsaewas significantly lower at 15 degrees C than at 25 degrees C (75.5% and 96% adult mortality, respectively) but was still more virulent thanS. feltiaeat both temperatures (29.5% and 39% adult mortality, respectively). These results show thatS. carpocapsaecould constitute a viable biological control agent forC. ciliata.