SEX-PHEROMONE OF THE FRENCH BLACK CUTWORM MOTH, AGROTIS-IPSILON (LEPIDOPTERA, NOCTUIDAE) - IDENTIFICATION AND REGULATION OF A MULTICOMPONENT BLEND

The sex pheromone blend of a European strain of the black cutworm moth , Agrotis ipsilon (Hufnagel), was investigated. Chemical analyses of p heromone gland extracts from 4- to 8-day-old females showed that indiv idual isolated glands contained only very small amounts of pheromone. High-resolution gas chromatography combined with mass spectrometry (CC -MS) analyses showed the presence of cis-7-dodecenyl acetate (Z7-12:Ac ), cis-9-tetradecenyl acetate (Z9-14:Ac), cis-11-tetradecenyl acetate (Z11-14:Ac), cis-11-hexadecenyl acetate (Z11-16:Ac), and cis-11-hexade cenol (Z11-16:OH) in biologically active pheromone gland extracts. Rem oving 27-12:Ac, Z9-14:Ac, or Z11-16:Ac from the complete gland extract by GC trapping techniques strongly reduced the attractiveness of the pheromone blend tested in a wind tunnel. Lack of cis-5-decenyl acetate (Z5-10:Ac) or Z11-16:OH did not affect the blend attractiveness. Chem ical and behavioral analyses showed that pheromone components are prod uced during photophase, at least 2 hr before lights off. Quantitative data showed that decapitation inhibited the production of Z7-12:Ac, Z9 -14:Ac, Z11-14:Ac, Z11-16:Ac, and Z11-16:OH, but production in decapit ated females was stimulated in response to injection of synthetic Heli othis tea PBAN (pheromone biosynthesis activating neuropeptide) or A. ipsilon brain-subesophageal (Br-SEG) homogenates. Moreover, upon injec ting BR-SEG homogenates, other minor components were detected, which w ere tentatively identified as cis-8-dodecenyl actetate (Z8-12:Ac) and Z5-10:Ac. Our study demonstrated that Z11-16:Ac is one of the main act ive components produced by the pheromone gland of this European popula tion of A. ipsilon, in addition to Z7-12:Ac/Z9-14:Ac, which were inves tigated in a previous behavioral analysis. All these data strongly sug gest that some polymorphism is present in pheromone communication in d ifferent strains of A. ipsilon.