Selection of suitable cereal cultivar as living mulch for retentionof natural enemiesof pests of Welsh onion

Abstract

We tested two cultivars of barley and one of wheat as living mulch for the retention of indigenous natural enemies of pests of winter-harvested Welsh onion. 'Hyakumangoku' barley withered earliest and was therefore most suitable to precede soil hilling for the blanching of the onions in early September; it supported populations of Rhopalosiphum padi (Linnaeus) and Anaphothrips obscurus (Müller), which are food sources for the indigenous natural enemy Geocoris proteus Distant, and various predatory phytoseiid mites.

Predacious Natural Enemies Associated With Suppression of Onion Thrips, Thrips tabaci (Thysanoptera: Thripidae), in Intercropped Onion-Barley Agroecosystems

“…Consequently, alternative control methods to insecticides are required to manage them (Woldemelak 2020). Several studies have reported that intercropping of barley with an allium crop increased natural enemies, such as phytoseiid mites, predatory hemipteran bugs (e.g., Geocoris spp., Geocoridae), ground-dwelling spiders (e.g., Lycosidae and Linyphiidae), and ground beetles (Coleoptera: Carabidae), which might control onion thrips (Tsuchida et al 2015, Doi et al 2016, Oida et al 2017, Sekine et al 2021). The barley intercropping strategy clearly has considerable potential and might provide a more stable strategy to control thrips, while reducing insecticide use.…”