Waterworth Rebeccah A, Robinson Lindsay J, Redak Richard A, Morse Joseph G
Environ Entomol. 2016 Feb;45(1):83-93. doi: 10.1093/ee/nvv168.
Acutaspis albopicta (Cockerell) is an exotic scale detected on imported ‘Hass’ avocados arriving in California from Mexico. An effort was made to understand how well this species might be biologically controlled by the parasitoid, Aphytis melinus DeBach. In no-choice trials, single life stages of A. albopicta and Aonidiella aurantii (Maskell) were exposed to one Ap. melinus female. Ap. melinus attacked and developed to adult on all A. albopicta life stages tested, which included early, middle, and late male and female second instars, and early, middle, and late female third instars. However, the proportion of scales attacked was relatively low (≤20%), as were the number of eggs laid on each scale stage. In six of seven comparisons of scale cover surface area between A. albopicta and Ao. aurantii that were similarly aged, Ao. aurantii was significantly larger. With intraspecific choice trials, females of Ap. melinus strongly preferred to parasitize the oldest and largest female scales in both single- and mixed-sex offerings. Younger, smaller scales were preferred for host feeding. Five comparisons of preference between A. albopicta and Ao. aurantii showed that Ap. melinus preferred 28- and 36-d-old Ao. aurantii females over similarly aged A. albopicta. However, Ap. melinus preferred 23-d-old males of A. albopicta. In three of five comparisons, Ao. aurantii was the preferred species to host feed on. More F1 females of Ap. melinus were recovered from both intraspecific choice trials compared with any stage in no-choice trials. Implications of incorporating Ap. melinus into biological control programs are discussed.
白纹锐盾蚧（Acutaspis albopicta (Cockerell)）是一种在从墨西哥运往加利福尼亚的进口‘哈斯’牛油果上发现的外来蚧虫。人们努力了解寄生蜂——孟氏隐唇瓢虫（Aphytis melinus DeBach）对该物种的生物防治效果如何。在无选择试验中，将白纹锐盾蚧和橙黄粉蚧（Aonidiella aurantii (Maskell)）的单个虫态暴露于一只孟氏隐唇瓢虫雌虫。孟氏隐唇瓢虫攻击了所有测试的白纹锐盾蚧虫态并发育至成虫，这些虫态包括早、中、晚期的雄雌二龄若虫，以及早、中、晚期的雌三龄若虫。然而，被攻击的蚧虫比例相对较低（≤20%），在每个蚧虫阶段产下的卵数也较低。在七个对白纹锐盾蚧和年龄相近的橙黄粉蚧的蚧壳覆盖表面积的比较中，有六个显示橙黄粉蚧的蚧壳显著更大。在种内选择试验中，孟氏隐唇瓢虫雌虫在单性别和混合性别的蚧虫供体中都强烈偏好寄生最老且最大的雌蚧。较年轻、较小的蚧虫更受寄主取食的青睐。对白纹锐盾蚧和橙黄粉蚧的五次偏好比较表明，孟氏隐唇瓢虫更喜欢28日龄和36日龄的橙黄粉蚧雌虫，而非年龄相近的白纹锐盾蚧。然而，孟氏隐唇瓢虫更喜欢23日龄的白纹锐盾蚧雄虫。在五次比较中的三次，橙黄粉蚧是寄主取食的首选物种。与无选择试验的任何阶段相比，从种内选择试验中回收的孟氏隐唇瓢虫F1代雌虫更多。讨论了将孟氏隐唇瓢虫纳入生物防治计划的意义。
