Efficacy of Amblyseius largoensis (Muma) as a biocontrol agent of the red palm mite Raoiella indica (Acari: Tenuipalpidae)

The red palm mite, Raoiella indica Hirst (Acari: Tenuipalpidae), is a severe pest of coconut ( Cocos nucifera L.), banana ( Musa sp.), and some ornamental palms. The predatory mite Amblyseius largoensis Muma (Acari: Phytoseiidae) has been reported in association with R. indica in several countries. Here, we assessed the interaction effect between prey density and population structure on predation and fecundity of this phytoseiid species. Specifically, we estimated the predation capacity of nymphs and females of A. largoensis based on their functional and numerical responses when fed on eggs, immature stages (deutonymphs or protonymphs), and females of R. indica . Nymphs and females of A. largoensis presented type II functional responses to R. indica , except for nymphs of the predator when consuming immature stages of the pest that exhibited a type III functional response. Nymphs and females of the predator showed a higher attack rate and shorter handling time when feeding on eggs of R. indica than on immatures and females. The highest oviposition rates of A. largoensis were observed when eggs and immatures of the pest were offered as prey. The results indicate that nymphs and females of A. largoensis may be effective in suppressing R. indica populations, mainly at lower prey densities.