Chaetosiphon fragaefolii Cockerell (Hemiptera: Aphididae) is a worldwide strawberry pest with scarce records of parasitoids for its control. The parasitization rate of two generalist parasitoids, Aphidius colemani Viereck and Aphidius matricariae Haliday, their behavior and aphid defensive behaviors were evaluated with Aphis gossypii Glover (Hemiptera: Aphididae) as a comparative host. Defensive endosymbionts were also surveyed. C. fragaefolii was never parasitized in simple-choice tests, whereas in preference tests both parasitoids chose A. gossypii over C. fragaefolii. No contacts of A. matricariae with C. fragaefolii were observed while A. colemani made more antennal contacts and “stings” on A. gossypii than on C. fragaefolii with the latter exhibiting less defensive behaviors against the parasitoid. The bacterium Acinetobacter sp. was detected in all samples of C. fragaefolii, but with an unknown function. Further research on the possible defensive role of the glandular hairs covering the body of this aphid, the role of chemical signals and the existence of defensive internal mechanisms against parasitoids could provide plausible explanations for the absence of parasitism found.

Chaetosiphon fragaefolii Cockerell（半翅目：蚜虫）是一种世界范围内的草莓害虫，控制寄生虫的记录很少。以棉蚜Aphis gossypii Glover（半翅目：蚜虫）作为比较宿主，评估了两个普通寄生虫（Aphidius colemani Viereck和Aphidius matricariae Haliday）的寄生率，它们的行为和蚜虫防御行为。防御性共生菌也进行了调查。Ç。在简单选择测试中，从来没有寄生过fragaefolii，而在偏爱测试中，这两种寄生虫都选择了A. gossypii而不是C. fragaefolii。无触点A. matricariae与观察到C. fragaefolii，而A. colemani在A. gossypii上比在C. fragaefolii上有更多的触角接触和“刺”，后者对拟寄生物的防御行为较少。细菌不动杆菌属。在所有C. fragaefolii样品中均检测到，但功能未知。对覆盖该蚜虫身体的腺毛可能的防御作用，化学信号的作用以及对寄生虫的防御内部机制的存在的进一步研究，可以为发现的无寄生虫提供合理的解释。