Efficacy of entomopathogenic nematodes in peat alternative growing media

Abstract: Entomopathogenic nematodes (EPNs) are widely used to control invertebrate pests
of protected crops. In ornamental and soft fruit crops EPNs have often replaced the use of
synthetic insecticides for the control of vine weevil, Otiorhynchus sulcatus, larvae. While the
efficacy of EPNs has been well established, direct comparisons between studies is made
difficult by the range of environmental conditions, crop and cropping system, application
technique, EPN species and growing media used in each study. To address this problem, we
completed a meta-analysis in order to collate available information on the efficacy of EPN
species against vine weevil larvae in both soft fruit and ornamental crops. Results from this
meta-analysis confirms the efficacy of five EPN species against vine weevil larvae but also
highlights the importance of cropping system and application method in determining the
strength of response recorded. Results also indicate that relatively few studies have tested the
efficacy of EPNs in peat alternative growing media. As a result, additional experimental work
was completed testing the efficacy of EPNs against vine weevil larvae in a range of peat
alternative growing media including bark, wood fibre, coir and green compost.