(Z)-5-tetradecen-1-ol: A secondary pheromone of the yellowheaded spruce sawfly, and its relationship to (Z)-10-nonadecenal
The yellowheaded spruce sawfly,Pikonema alaskensis (Rohwer), was known to possess a potent secondary pheromone with the polarity of an alcohol, based on earlier studies with Florisil fractions. Purification of the 25% ether-hexane Florisil fraction (polarity as with alcohols) and the hydrolyzed 5% ether-hexane fraction (polarity as with esters) from 50,000 females yielded a total of ca 3μg of an active compound identified as (Z)-5-tetradecen-1-ol (Z5–14∶ OH). When added to 100 ng of (Z)-10-nonadecenal (Z10–19∶Al), which behaves as the primary pheromone in this sawfly, 0.5 ng of syntheticZ5–14∶ OH caused an 8.8-fold increase in the greenhouse bioassay response, compared toZ10–19∶Al alone.E5–14∶ OH caused a 2.8-fold increase. Only the combination ofZ5–14∶ OH andZ10–19∶ Al consistently elicited mating attempts among males. When Hercon® formulations ofZ5–14∶OH andZ10–19∶ Al were used together to bait traps, catches were up to four times higher than for theZ10–19∶ Al alone, but this increase was seen only after emergence and mating activity in the field population were virtually complete. TheZ5–14∶ OH was inactive alone, and at higher levels it depressed trap catches toZ10–19∶ Al. The Hercon formulations ofZ5–14∶ 0H andZ10–19∶Al together were as attractive as virgin females.Z10–19∶Al alone and the (Z,Z)-9,19 hydrocarbon dienes (found in all females and able to oxidize in air to produceZ10–19∶Al) were similar to mated females. ThusZ5–14∶:OH accounted for the difference in attractiveness between virgin and mated females.
Evidence for a multicomponent sex pheromone in the yellowheaded spruce sawfly
The existence of a female-produced sex pheromone in the yellowheaded spruce sawfly,Pikonema alaskensis (Rohwer) (Hymenoptera: Tenthredinidae) was demonstrated by field and greenhouse bioassays. Virgin females, their empty cocoons (with which they were confined during handling procedures), and the hexane extract of these cocoons were attractive in the field. The only Florisil fraction of this extract consistently attractive by itself was that eluted with hexane, but three, more polar fractions (eluted with 5%, 25%, and 50% ether in hexane) each synergized the hexane fraction, increasing bioassay responses 10–30 times. Fractions derived directly from virgin females yielded comparable results. The greenhouse data corroborated the field data, except that the 5% ether-hexane fraction, while very synergistic in the field, was consistently inactive in the greenhouse.
Inhibition of the Sexual Behavior of the Smaller Tea Tortrix Moth by the Sex Pheromone and Its Components
チャノコカクモンハマキの性フェロモンおよびその構成成分であるcis-9-tetradecenyl acetate (cis-9-TDA)およびcis-11-tetradecenyl acetate (cis-11-TDA)は,室内条件ガラス容器内でこのハマキガの交尾を阻害した。cis-9-TDA,cis-11-TDA,および両者の7対3混合物による90%阻害濃度は20°C, 14L-10D条件下でそれぞれ3, 0.3,および3μg/lであった。trans体による交尾阻害効果はこの条件下ではきわめて低かった。これらの化合物をほ場に均一に蒸散させた場合,cis-9-TDA, cis-11-TDA,および混合物いずれの処理の場合も処女雌トラップの雄の飛来を阻害した。しかし,これらの化合物およびtrans異性体を処女雌トラップに付置した場合には,trans異性体およびその混合物のほうがcis体よりも強く処女雌トラップの誘引性を抑え,室内条件下でもっとも強い交尾阻害を示したcis-11-TDAはむしろcis-9-TDAに劣る誘引阻害を示した。