影響桔粉介殼蟲寄生蜂（Leptomastix dactylopii Howard）性比之各種因子

Factors Affecting the Sex Ratio of Leptomastix dactylopii Howard, a Parasitoid of Planococcus citri (Risso)

蘇宗宏(Tsong-Hong Su) ； 李奇倉(Chi-Tsang Li)

《中華昆蟲》 13卷4期 (1993/12) Pp. iii+319-329

https://doi.org/10.6660/TESFE.1993030

摘要

桔粉介殼蟲寄生蜂(Leptomastix dactylopii Howard)是桔粉介殼蟲(Planococeus citri (Risso))之單元內寄生蜂。本研究之目的是在實驗室內研究影響寄生蜂子代性比之各種因子。寄生蜂可寄生在不同日齡的桔粉介殼蟲，寄生蜂子代雄性比率以14日齡最高平均為70.0%，42日齡最低平均為45.5%，寄生蜂子代雄性比率隨著寄主日齡增加而下降，子代數量亦隨寄主日齡增加而上升。寄生蜂寄生不同密度的桔粉介殼蟲，寄生蜂子代雄性比率，以寄生在較低密度寄主20隻時最低為31.0%，寄生在較高密度寄主300隻時，最高45.1%，其雄性比率隨著寄主密度增加而昇高。寄生蜂在35℃高溫產卵時，會影響其子代的雄性比率。寄生蜂在15℃低溫產卵時，則雄性比率無顯著差異。寄生蜂子代性比率不因雌性寄生蜂密度不同而有差異，顯示雌性寄生蜂密度不影響其子代雄性比率。隨著雌性寄生蜂密度增加，其產生子代數量也隨著增加，平均每1隻寄生蜂的子代產量，以接50隻寄生蜂的4.1隻最高。寄生蜂在第1日齡至12日齡產卵時，其子代雄性比率無顯著差異，顯示寄生蜂在不同日齡產卵，不響其子代的性比。子代數量則以第3及第6日齡較多，剛羽化交尾完成之第1日齡及日齡較久之第9及第12日齡寄生蜂其生產子代數量較少。供給寄生蜂不同食物，不影響寄生蜂子代的雄性比率。

關鍵字

桔粉介殼蟲 ； 桔粉介殼蟲寄生蜂 ； 寄生蜂 ； 性比

並列摘要

Leptomastix dactylopii Howard (Hymenoptera: Encyrtidae) is a solitary endoparasitoid of the citrus mealybug, Planococcus citri (Risso). The objective of this research was to investigate the factors that affect the sex ratio of L. dactylopii in a laboratory environment. L. dactylopii operated as a parasite of P. citri at various ages. The male sex ratio of progeny of L. dactylopii emerging from parasitized 14-day-old hosts was 70%, and that from 42-day-old hosts was 45.5%. The sex ratio of progeny of L. dactylopii parasitizing large hosts favoured the females, but small hosts favoured the males. The male sex ratio of progeny decreased as the age of the host increased, but progeny production increased as host age increased. L. dactylopii provided with 20 hosts produced progeny with the smallest male sex ratio 31 %, whereas the greatest male sex ratio 45% was obtained for those provided with 300 hosts. The male sex ratio increased with increasing host density. A high temperature (35°C) affected the male sex ratio of the progeny of L. dactylopii, but there was no effect at 15°C. No significant distinction in sex ratio was observed between the progeny produced by various densities of L. dactylopii. The total production of progeny increased with increasing density of female parasitoids. The greatest production of progeny was found at a density 50 female parasitoids, producing 4.1 progen per female. The sex ratio varied in significantly among progeny produced by females aged 1-12 days. The production of progeny of females at age s 3 and 6 days was greater than that of 1, 9 and 12 days. No distinction was found in the male sex ratio of the progeny from female parasitoids depending on varied foods.

並列關鍵字

Planococcus citri ； Leptomastix dactylopii ； parasitoid ； sex ratio