Compounds modifying the activity of two sex attractants for males of the pea moth,Cydia nigricana (F.).

(E)-10-Dodecen-1-yl acetate (E10-12∶Ac) and (E,E)-8,10-dodecadien-1-ylacetate (E,E8,10-12∶Ac) are sex attractants for males of the pea moth,Cydia nigricana (F.). Thirty-two structurally related compounds with chain lengths of 9-14 carbon atoms were exposed withE10-12∶Ac orE,E8,10-12∶Ac in traps in the field to investigate their influence on the activity of the attractants. Only alchols and acetates unsaturated at C-8, -9, or -10 greatly influenced moth captures. (Z) and (E)-8-dodecen-1-ol were weak synergists forE10-12∶Ac but no synergists forE,E8,10-12∶Ac were found. (Z) and (E)-8-dodecen-1-yl acetate and (E,E)-8,10-dodecadien-1-ol inhibited bothE10-12∶Ac andE,E8,10-12∶Ac while (E)-10-dodecen-1-ol, 10-dodecyn-1-ol, (Z) and (E)-9-dodecen-1-yl acetate, (Z)-10-dodecen-1-yl acetate, and undecyl acetate inhibited only the former attractant.