Burgeoning consumer interest in organically produced foods has made organic farming one of the fastest growing segments of agriculture. This growth has not been supported adequately by rigorous research to address challenges such as arthropod pest management. The research that has been conducted, however, is complemented by research in aspects of conventional agriculture that may have applicability in organic systems, as well as by research in underpinning fields such as applied ecology. This article synthesizes the available literature in relation to a conceptual model of arthropod pest management strategies suitable for organic systems. The present work uses the four phases of the model to review the strategies in an agroecological context and provides a synthesis of the factors that influence the success of each phase. Rather than constituting a fringe science, pest management research for organic systems draws on cutting edge science in fields such as landscape and chemical ecology and has a bright future.

Selected weeds were used to attract antagonists of apple aphids in an apple orchard near Berne, Switzerland. In the year before the experiment, in 1991, the apple aphids Dysaphis plantaginea (Pass.) and Aphis pomi (DeGeer) and aphidophagous predators were homogenously distributed in the orchard. In April 1992, weed strips were sown between tree rows and along the border parallel to the first and the last row of trees in one part (the other part served as control). In both parts of the orchard, randomly chosen trees were controlled visually in weekly intervals in 1992 and 1993. During flowering of weeds more aphidophagous predators were observed on the apple trees within the strip-sown area than in the control area. The most abundant and permanent aphidophagous predators were spiders, predaceous Heteroptera, Coccinellidae, and Chrysopidae. Both species of aphids were significantly less abundant in the area with weed strips than in the control area during the vegetation period. The effects of the weed strips on aphidophagous predators, and those of predators on aphids, are discussed.

Aphids and their predators were studied in an apple orchard near Berne, Switzerland. To augment the density of the predators of aphids weed strips were sown in tramlines and along the border parallel to the first and the last row of trees in one half of the orchard (the other half served as control) in April 1992. Weekly visual observations, monthly beating-tray samples, branch samples in winter, and assessment of the density of spider webs and their trapping efficiency on randomly chosen trees were carried out in 1993. During 1993, significant differences in the number of aphids, aphidophagous insects, and spiders were observed on the apple trees within both the strip-managed area and the control area. The impact on aphids by the aphidophagous insects was important during the flowering time of weeds in spring and summer. In autumn, however, spiders (i.e. Araniellu spp.) were the dominant predators of aphids on the trees; during this time of the year they were more abundant within the strip-managed area of the orchard. With a higher density of webs, spiders significantly reduced the number of aphids able to return from their summer host plants. Consequently, less hatching aphids were found on branch samples of the strip-managed area compared to the control area. The effects of the weed strips on spiders and aphidophagous insects, and the resulting impact of predation on the aphids are discussed.

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The effects of six fungus isolates on the mortality of different life stages of the European cherry fruit fly, Rhagoletis cerasi (Diptera: Tephritidae), were assessed in a series of laboratory experiments to find an isolate suitable for biological control. In a first step, the effects of fungus treatments on mortality, mycosis and fecundity of adult flies at a concentration of 107 conidia/ml were evaluated. All fungus isolates caused mycosis but virulence varied considerably among the isolates. Beauveria bassiana and Isaria fumosorosea caused 90–100% mortality and had the strongest influence on fecundity. Metarhizium anisopliae also induced high rates of mortality, while the pathogenicity of Isaria farinosa was low. The effects of lower conidia concentrations and the influence of the age of flies were assessed in a second step. Higher conidia concentrations generally resulted in a higher mortality. B. bassiana was most efficient at low concentrations. Young flies showed lower mortality rates than older flies but, sub‐lethal effects on eclosion rate of eggs were greater in younger flies. Finally, the effects on L3 larvae were tested: none of the fungus isolates induced mortality in more than 25% of larvae. As L3 larvae and pupae are not susceptible to fungus infection, field control of R. cerasi should be focused on adult flies.