(35(4):521-529)Field Trapping of the Diamondback Moth by Using Synthetic Sex Pheromone－I. Tests on the Synergistic Effects of Sex Pheromone Analogues and the Effective Distance of Sex Pheromone Lure of Diamondback Moth in Field

本試驗目的為探明小菜蛾（Plutella xylostella）性費洛蒙（Z11-16 : Ald + Z11-16 : Ac）添加其類似物（Z11-16 : OH 或Z9-14 : Ac）是否影響其田間誘雄效果，並探測該劑之誘雄距離。試驗結果得知性費洛蒙在冬季若以1 : 1 : 0.02 與1 : 1 : 0.01之比例添加Z11-16 : OH 與Z9-14 : Ac，劑量為10 μg時，其誘力均增強，分別約為未添加者之1.5 與1.7-4.3 倍。若在夏季添加則無增效作用。又兩種性誘劑Z11-16 : Ald + Z11-16 : Ac +Z11-16 : OH ( l : l : 0.02）與Z11-16 : Ald + Z11-16 : Ac + Z9-14 : Ac ( l : l : 0.001 )，劑量為10 或100 μg，與對照組（5 隻活處女蛾）在其下風處0.5、1.0、1.5及3.0m釋放標記雄蛾，各處理之誘雄力均無顯著差異。性誘劑在田間之誘雄有效距離為1.0m。 Three analogues, Z1l- hexadecenol(Z11-16 : OH), Z9-tetradecenyl acetate(Z9-14 : Ac) and Z9-hexadecenyl propionate (Z9-16 : P), were individually added to the synthetic sex pheromone (Z11-16 : Aid ±Z11-16 : Ac) of diamondback moth (Plutella xylostella, DBM) for testing its synergistic effects on the DBM males caught in field. In winter, the number of moths caught by a mixture of Z11-16 : Aid, Z11-16 : Ac and the 3rd compounds ( Z11-16 : OH or Z9-14 Ac) in the ratio of 1 : 1 : 0.02 or 1: 1 : 0.001 showed 1.5 or 1.7 to 4.3 times respectively than the sythetic sex pheromone used alone. However, these two analogues did not show synergistic effect on DBM males caught. in summer Marked adult males of DBM were released in cabbage field at 4 points located at 0.5, 1.0, 1.5 and 3.0m far from a pheromone trap. Five different kinds of lure sources were used in the traps e.g., Z11-16 Ald +Z11-16 : Ac + Z11-16: OH (1: 1 : 0.02) and Z11-16 : Ald+Z11-16 : Ac+Z9-14 : Ac (1: 1 : 0.001) in 10, and 100μg dosages respectively, and with 5 virgin females as check. The number of recaptured marked males indicated that the distance downwind of the active distance was 0.5 to 1.0m, but no difference were shown among the 5 treatments. Z11-16 Aid +Z11-16 : Ac +Z11-16 : OH (1 : 1: 0.02) with 50, and 100μg dosages per trap were set up at distance of 2.2-11.0m indicated that the maximum active space between lure traps was 2.2-3.6m