Strand M R
Department of Entomology, University of Wisconsin-Madison, 53706, Madison, WI, USA.
Department of Entomology, Clemson University, 29634, Clemson, SC, USA.
Oecologia. 1988 Nov;77(2):219-224. doi: 10.1007/BF00379189.
The sex allocation behavior of the solitary egg parasitoid Telenomus heliothidis Ashmead was investigated by examining the response of females reared in isolation and under crowded conditions. Females reared in isolation adjusted their sex ratio with foundress and host number per patch in accordance with the predictions of local mate competition (LMC) theory. However, females did not shift their sex ratio in response to conspecifics foraging on the same host patch or to contact with previously parasitized hosts. Instead, shifts were associated with encounter rate and a sequence of oviposition. Females maintained under crowded conditions responded to host patches much differently. One-day-old females which had lived under crowded conditions for 24 h produced sex ratios similar to those of continuously isolated females. However, females reared under crowded conditions for 7 days consistently produced unbiased sex ratios, and exhibited a different sequence of oviposition. This shift appeared to be due directly to crowding rather than age, oviposition experience or sperm depletion since the effect could be reversed by subsequent isolation.
通过研究单独饲养和拥挤条件下饲养的雌性个体的反应，对独居卵寄生蜂烟夜蛾黑卵蜂（Telenomus heliothidis Ashmead）的性别分配行为进行了调查。单独饲养的雌性个体根据局部配偶竞争（LMC）理论的预测，随着每个斑块中雌虫和寄主数量的变化调整其性别比例。然而，雌性个体不会因同一寄主斑块上的同种个体觅食或与先前被寄生的寄主接触而改变其性别比例。相反，性别比例的变化与相遇率和产卵顺序有关。在拥挤条件下饲养的雌性个体对寄主斑块的反应大不相同。在拥挤条件下生活24小时的1日龄雌性个体产生的性别比例与持续单独饲养的雌性个体相似。然而，在拥挤条件下饲养7天的雌性个体始终产生无偏差的性别比例，并且表现出不同的产卵顺序。这种变化似乎直接归因于拥挤，而不是年龄、产卵经验或精子耗尽，因为这种影响可以通过随后的隔离而逆转。
