摘要:

Abstract.The ability of male spruce budworm moths,Choristoneura fumiferana(Clem.), to orientate to and locate virgin female moths was investigated in a laboratory wind tunnel. When presented with two caged ‘target female’ moths, more than 99% of the male moths locked on and flew directly to the females. When confined for 3 h before release, downwind of a three‐dimensional array of thirty‐five evenly distributed female moths (a density of 40/m3), over 90% of the males still successfully oriented to one or another of the females, although not always to the target females. With an array of thirty‐five septa containing either E‐11‐tetradecenyl acetate on E‐11‐tetradecenol there was no visible change in behaviour;>90% of the males flew directly to the two target females, which indicates that neither the acetate nor the alcohol has potential for mating disruption. An array of thirty‐five septa containing a 955 blend of E‐ and Z‐11‐tetradecenal, the main components of the spruce budworm sex pheromone, significantly reduced the numbers of male moths able to locate the target females, and effects were concentration‐dependent. The highest concentration, which gave a release rate similar to that of a calling female, produced the same level of disruption as the thirty‐five females, but sensory fatigue became a factor in addition to ‘false trail following’. Lower concentrations were significantly less effective, with no evidence of sensory fatigue. At all concentrations significant numbers of males flew to the septa (false trail following), but when male moths were left uncaged in the tunnel for a further 3h, most eventually located the females. This suggests that false trail following alone will not prevent mating. The level of disruption was not improved by the addition of 2% tetradecanal to the 955 blend. Similar levels of disruption to the 955 blend were obtained with an 80:20 blend. A 5050 blend still caused a significant amount of false trail following, but less than the other blends. The ability of male spruce budworm to orientate to off‐blend trails was enhanced if the males were first exposed to the

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1995.tb00803.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Abstract.In addition to the pheromone components (Z)‐5‐decenyl, (Z)‐7‐dodecenyl and (Z)‐9‐tetradecenyl acetate (Z5‐10:OAc, Z7‐12:OAc and Z9‐14:OAc), it has previously been shown that the sex pheromone gland of the turnip moth,Agrotis segetum(Lepidoptera: Noctuidae Schiff) contains 10:OAc, 12:OAc, Z5‐12:OAc, Z9‐12:OAc, 11–12:OAc, Z5‐14:OAc, Z7‐14:OAc and Z11‐16:OAc. To find out whether any of these additional compounds is involved in the sex pheromone communication inA. segetum, a comprehensive electro‐physiological and behavioural investigation was conducted. Single‐sensillum recordings on male antennae revealed three subtypes of sensilla among the previously so‐called Z5‐10:OAc sensilla. One subtype was identified having one receptor neurone (A) that responded to Z5‐10:OAc with a large spike amplitude and another neurone (B) that responded to (Z)‐5‐decenol (Z5‐10:OH) with a small spike amplitude. In another subtype the B neurone responded to Z5‐12:OAc and sometimes also to 27‐12:OAc and 10:OAc, in addition to responding to Z5‐10:OH. In a third subtype the A neurone responded to all acetates identified from the female pheromone gland, whereas the small spike amplitude neurone was tuned to Z5‐10:OH. A flight tunnel assay showed that blends composed of nine, eight or seven compounds were equivalent to the previously identified three‐component pheromone blend in eliciting male behavioural responses. In field trapping tests, blends of eleven, nine or seven compounds did, however, catch significantly more moths than the three‐component blend. Further assays showed that only 25‐ 12:OAc could significantly increase the catch numbers when added to the three‐component blend, and thus qualified as a fourth pheromone component inA. segerum.The behavioural significance of additional female‐produced acetates — for which males possess antennal receptors — is suggested, but may be impossible to confirm because of ‘diminish

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1995.tb00804.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY