Pathogenicity, Distribution, and Persistence of Entomopathogenic Nematode Against <i>Rhynchophorus ferrugineus</i> in Naturally Infested Date Palm Trees

ABSTRACT A sustainable, eco‐friendly system has been developed to manage red palm weevil (RPW), Rhynchophorus ferrugineus (Olivier) (Coleoptera: Curculionidae). The system uses entomopathogenic nematodes (EPNs) to manage RPW population in infested date palm orchards. Early detection of RPW can be achieved through an optimized device, an acoustic sensor. An acoustic sensor was utilized to track the efficacy of EPNs against RPW in date palm trees. Two indigenous EPN isolates, Steinernema carpocapsae (Weiser) ScSA‐1 (Rhabditida: Steinernematidae) and Heterorhabditis indica Poinar, Karunakar &amp; David, authority HiSA‐1 (Rhabditida: Heterorhabditidae) and one exotic isolate S. carpocapsae from Palmanem, were injected into infested date palm trunks, with each tree receiving 10 6 infective juveniles. After the application of EPNs, RPW activity was monitored weekly by recording the impulse burst rates ( rs ) with the acoustic sensor. For all applications over a 10‐week period, we present the average weekly burst rates of RPW sound activities in treated trees. At 6 weeks after application, the mean burst rates in each treatment showed a significant decrease compared to the control group. For the Palmanem and HiSA‐1 treatments, the mean burst rates decreased to levels that indicated a low probability of infestation within 6 weeks of application, and they remained at zero. After 7 weeks, the mean RPW burst rate in the ScSA‐1 application also decreased. EPNs persistence was monitored for 10 weeks. We found that ScSA‐1, HiSA‐1, and Palmanem EPNs persisted at high numbers in date palm trees after one or two weeks post injection, whereas a significant decrease was observed after 6 weeks of application. All treatments reduced RPW infestation for 7 weeks in the treated date palm trees and supported the pest control program by showing high spread and persistence. Further research may improve EPN efficacy and persistence inside date palm trunks, establishing EPNs as the most environmentally benign biological control agents against RPW.