Individual study: Using field margin diversification in agri-environment schemes to enhance aphid natural enemies
Powell W., Walters K., A\'Hara S., Ashby J., Stevenson H. & Northing P. (2003) Using field margin diversification in agri-environment schemes to enhance aphid natural enemies. IOBC/wprs Bulletin, 26, 123-128
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
Plant nectar flower mixture/wildflower strips
A replicated, controlled before-and-after study from 2000 to 2002 in winter cereal fields on four UK farms (Powell et al. 2003) found no significant effects of flower-rich margins or an aphid sex-pheromone treatment (nepetalactone, designed to enhance Aphidiinae parasitoid wasps that use aphids as their hosts) on aphid populations due to cold and wet weather at the beginning of summer 2001, resulting in small parasitoid populations. Invertebrates were sampled by in situ counting, suction-sampling, pan-traps and pitfall traps along four transects in three fields (with or without wildflower-rich/tussocky grass margins) on each farm. Sex-pheromone was released from formulated strips in the grassy field margin in autumn and in the crop in spring, starting autumn 2000. This study was part of the same experimental set-up as Powell et al. 2004.