Gut content analysis of extra- and intraguild prey in ground dwelling predators and field densities of prey and predators

The experiment took place in 10 organic and conventional spring barley fields in south-central Sweden located in pairs during the early barley tillering ('Early' period) and at barley stem extension/heading stage ('Late' period). 3680 generalist ground-dwelling predators (carabids and spiders) were collected for gut content analysis with primers targeting: - extraguild prey: aphids, thrips, dipterans, springtails and earthworms - intraguild prey: Carabids: Harpalus, Pterostichus, Poecilus, Bembidion; and Spiders: Lycosidae, Linyphiidae, Pachygnatha spp; other: Coccinella septempunctata and lacewings. Extraguild prey density and intraguild prey activity density were recorded at Early and Late period.