The potential of Chrysoperla rufilabris and Doru taeniatum as agents for dispersal of Spodoptera frugiperda nucleopolyhedrovirus in maize

The behaviour of two abundant predators in Mesoamerican maize crops, Chrysoperla rufilabris larvae and Doru taeniatum adults, towards healthy and nucleopolyhedrovirus-infected Spodoptera frugiperda larvae was compared. C. rufilabris did not discriminate between healthy and virus-infected prey, although the mean search time was approximately two times longer towards virus-infected larvae. In contrast, D. taeniatum directed a greater proportion of their attacks towards virus-infected prey but there was no significant difference in the search time. Prey consumption time did not differ significantly for each type of prey by either predator, although prey consumption was much faster in D. taeniatum. Viable virus was detected in D. taeniatum faeces up to 3 d after feeding on infected S. frugiperda larvae, whereas virus was inactivated in the gut of C. rufilabris. Both predators were shown to have acidic guts. A field experiment demonstrated that D. taeniatum that had fed on infected prey could contaminate foliage resulting in the transmission of the disease at a low prevalence (4.7%) to S. frugiperda larvae in a field maize crop.