Understanding the prey preference of polyphagous predators is important to enhance their benefits as biocontrol agents. Two predators, Macrolophus basicornis (Stål) and Engytatus varians (Distant) (both Hemiptera: Miridae), attacking eggs of the two lepidopteran pests Tuta absoluta Meyrick (Lepidoptera: Gelechiidae) and Neoleucinodes elegantalis (Guenée) (Lepidoptera: Crambidae) were assessed under laboratory conditions. During 24 h predation rates of the two mirids were measured and their prey preference was quantified using Manly’s preference index. Behavioural patterns of each predator were observed during one hour and the following components were separated: moving, searching, resting, prey encountering, preying, feeding on leaflets and cleaning. Subsequently, encounter-, acceptance-, and predation rates were calculated. According to Manly’s preference index, E. varians had a strong preference for N. elegantalis when offered together with T. absoluta, while such a preference was not evident for M. basicornis. Compared to E. varians on T. absoluta M. basicornis spent more time searching for both prey and needed less time to encounter fresh eggs. Due to its higher attack rate, M. basicornis displayed a higher predatory efficiency on both pests. Both mirids spent longer time prey searching, resting and feeding (including sucking of leaflets) than on the remaining activities. Engytatus varians, however, spent more time feeding on plant tissue than M. basicornis. These results demonstrate the performance of both mirids as biocontrol agents against T. absoluta and N. elegantalis. Based on our results, we conclude that both mirids could be considered in pest management strategies in tomato crops.

了解多食性捕食者的猎物偏好对于增强它们作为生物防治剂的益处很重要。两种捕食者，Macrolophus basicornis (Stål) 和Engytatus varians (Distant)（均为半翅目：Miridae），攻击两种鳞翅目害虫Tuta absoluta Meyrick（鳞翅目：Gelechiidae）和Neoleucinodes egalalis 的卵（Guenée）（鳞翅目：蟹科）在实验室条件下进行评估。在 24 小时的捕食率期间，测量了两种 mirid 的捕食率，并使用 Manly 的偏好指数量化了它们的猎物偏好。在一小时内观察每个捕食者的行为模式，并将以下组成部分分开：移动、搜索、休息、遭遇猎物、捕食、喂食传单和清洁。随后，计算了遭遇率、接受率和捕食率。根据 Manly 的偏好指数，当与T. absoluta一起提供时，E. varians对N.qualityalis有强烈的偏好，而对M. basicornis则不明显。相比E. varians上T. absoluta M. basicornis花更多的时间寻找猎物，而遇到新鲜鸡蛋所需的时间更少。由于其较高的攻击率，M. basicornis对两种害虫都表现出更高的捕食效率。与其余的活动相比，这两种 mirid 在猎物搜索、休息和进食（包括吸食传单）上花费的时间更长。然而，与M. basicornis相比，Engytatus varians花在植物组织上的时间更多。这些结果证明了两种 mirids 作为生物防治剂对T. absoluta和N. egealis 的性能。根据我们的结果，我们得出结论，在番茄作物的害虫管理策略中可以考虑这两种 mirids。