Abstract
The rates of nictating Steinernema carpocapsae infective juveniles (IJs) were at most 20% and 10% for nematodes harvested from insect cadaver, Galleria mellonella, and for those from chicken offal medium, respectively. Repeated employment of nictating IJs for the nictation performance did not raise the rate, but kept almosthe initial levels. Accordingly, after four performances, the number of nictating individuals became 0.16% of the initial population. The nictating IJs were more attracted to the host cue (larval plasma of Spodoptera litura) and more penetrated to the host insect than did non-nictating IJs obtained from nematode-water suspension. There were no significant differences in the migration/penetration between the nictating IJs with and without insecticides; acephate, permethrin, and oxamyl at 50 pg/ml each. The experiments confirmed that nictating behavior was a positive or precursory behavior for infection of S. carpocapsae. Jpn. J. Nematol. 24 (1): 20-29(1994)
