Abstract
Tuta absoluta (Meyrick) has quickly developed into a significant tomato pest worldwide. While the recently found mirid predators Macrolophus basicornis (Stal), Engytatus varians (Distant) and Campyloneuropsis infumatus (Carvalho) of this pest are able to establish and reproduce on tomato, biological knowledge of these mirids is still limited. Here we describe the functional response of the three mirid predators of the tomato pest T. absoluta when offered a range of prey densities (four, eight, 16, 32, 64, 128 and 256 eggs) during a 24 h period inside cylindrical plastic cages in the laboratory. Engytatus varians and M. basicornis showed a type III functional response, whereas C. infumatus showed a type II functional response. At the highest prey densities, C. infumatus consumed an average of 51.0 eggs, E. varians 91.1 eggs, and M. basicornis 100.8 eggs. Taking all information into account that we have collected of these three Neotropical mirid species, we predict that M. basicornis might be the best candidate for control of the tomato borer in Brazil: it has the highest fecundity, the largest maximum predation capacity, and it reacts in a density-dependent way to the widest prey range.
Highlights
Due to the ecosystem services provided by parasitoids, predators, and pathogens, populations of potentially damaging herbivorous insects are often maintained at tolerable levels [1,2]
We describe the results of a study concerning the functional responses of three mirid predators, M. basicornis, E. varians and C. infumatus, when offered a range of prey densities of the tomato pest T. absoluta during a 24 h period inside cages in the laboratory
Two of the three mirid predators, E. varians and M. basicornis, show a type III functional response: the percentage prey consumed at densities four and eight is relatively low, increases, and levels off and decreases at a density over 64 T. absoluta eggs
Summary
Due to the ecosystem services provided by parasitoids, predators, and pathogens, populations of potentially damaging herbivorous insects are often maintained at tolerable levels [1,2]. In order to decide what kind of biological control can be used—inundative, seasonal inoculative or classical/inoculative biological control [3]—it is important to know whether and how a natural enemy is able to bring pest numbers down to non-damaging densities. For classical and seasonal inoculative releases a natural enemy needs to possess strong enough numerical and functional responses, whereas for inundative releases such responses are appreciated but not necessary. The numerical response is the change in predator density as a function of the change in prey density [4]: as a result of an increase. Insects 2016, 7, 34 in prey density, predators have more food and offspring and, increase in numbers, and vice versa. The numerical response (a reproduction response) and the functional response (a predation response) determine the pest population regulation capacity of a predator [5]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
