Susceptibility of the bulb mite, Rhizoglyphus robini (Acari: Acaridae), to entomopathogenic fungi
Abstract: The bulb mite, Rhizoglyphus robini, is a serious pest of garlic, onion and other crops and its control is difficult due to its ability to develop resistance to acaricides. The aim of our study is to assess the possibility of biological control of R. robini using natural pathogens. For this purpose we conducted field collections of native entomopathogenic fungi (EPF), followed by laboratory evaluations to find the most effective EPF strains/species. Methods for recovery of new strains/species of EPF was based on Galleria trap baiting and elution of soil samples by water and cultivation using selective medium with dodine. Several strains of Lecanicillium sp., Isaria sp., Purpureocillium lilacinum, Metarhizium sp. and Beauveria sp. were isolated from garlic and onion fields in Israel. Their efficacy against R. robini is now evaluated under laboratory conditions. Preliminary results indicate that Isaria fumosorosea applied at concentration of 1 × 108 blastospores per ml of suspension does not cause any mortality in this pest.