The reduction of frit fly oviposition on seedling ryegrass by the presence of oats

Abstract

AbstractSeedling ryegrass and oat plants in various proportions were exposed to oviposition by frit fly in the laboratory. The growth stage of the ryegrass ranged from single‐leaved (unattractive as oviposition sites) to three‐leaved (almost immune to serious damage). Oat plants attracted most oviposition and their inclusion usually reduced oviposition on ryegrass, by up to 90%. Where the frit fly population density was so high that potential oviposition exceeded the availability of oviposition sites, inclusion of oats did not reduce the number of eggs laid on ryegrass.This approach does not, therefore, show promise of a reliable control method against severe primary attack in the field, but is potentially useful over an important range of population densities at which further control measures might otherwise be required. The inclusion of oats would also provide an early warning of damage.