Biological control of Phyllophaga vetula (Horn)¹ with entomopathogenic nematodes in various formulations and moisture conditions

The aim of this study was to determine the possibility of using formulations of entomopathogenic nematodes in two soil moisture conditions for effective control of larvae of white grub, Phyllophaga vetula (Horn) (Coleoptera: Melolonthidae). Mortality of P. vetula larvae was compared using Steinernema glaseri Steiner, Heterorhabditis bacteriophora Poinar, and Steinernema feltiae Filipjev in three forms of application (formulated in cadavers of Galleria mellonella L. larvae, bentonite pellet, and aqueous suspension) and two soil moisture conditions (moderate,11.8%, and high, 20.5%). The difference among treatments was very significant: S. glaseri was the most effective nematode, killing 75% of larvae when applied in aqueous suspension with moderate moisture. Next most effective was S. glaseri in cadavers with the same moisture conditions that killed 55%. The nematodes H. bacteriophora and S. feltiae applied in all three forms (aqueous medium, infected cadaver, and bentonite pellet) and with the two moisture conditions (11.8 and 20.5%) were statistically similar to the check and did not control Ph. vetula.