A. Quiroz et al., SEMIOCHEMICALS MEDIATING SPACING BEHAVIOR OF BIRD CHERRY-OAT APHID, RHOPALOSIPHUM-PADI FEEDING ON CEREALS, Journal of chemical ecology, 23(11), 1997, pp. 2599-2607
Olfactometry using an apterous individual of Rhopalosiphum padi (L.) s
howed an arresting effect by volatiles from a wheat seedling and a rep
ellent effect by volatiles from a wheat seedling infested with aphids
at a high population density (ca. 9 aphids/cm(2)). Four compounds, 6-m
ethyl-5-hepten-2-one, (-)- and (+)-6-methyl-5-hepten-2-ol, and 2-tride
canone, were identified by CC-MS in air entrainments from the wheat se
edlings with high aphid density but not from the wheat seedlings alone
. The mixture of the four compounds in the natural proportion countera
cted the attractivity of the volatiles from the intact uninfested whea
t seedling. The likely role of these compounds in the spacing behavior
of this aphid species, when present in high densities on wheat, is di
scussed.