Comparison between the repellency of the two groups of chemicals.

In both aphid species, chemicals binding exclusively OBP3 and/or OBP7 are much stronger repellents than other ligands with different spectra of binding. For A. pisum: χ2 = 13.970, d.f. 1, P<0.001; for M. persicae: χ2 = 96.044, d.f. 1, P<0.001.