Is predation of Tuta absoluta by three Neotropical mirid predators affected by tomato lines with different densities in glandular trichomes?

Plants with glandular trichomes may provide protection against herbivores by impeding their movement, but may also hinder natural enemies. We investigated walking behavior and predation rates of the mirid predators Campyloneuropsis infumatus, Engytatus varians, and Macrolophus basicornis on two tomato lines with different densities of sticky trichomes. Also, the time spent by each predator species in various activities (immobile, walking, grooming, probing, and feeding) and the searching for and handling time of prey, eggs of Tuta absoluta, were observed. Tomato lines TOM 587 and TOM 687 were used, with TOM 687 having a 179% higher density of glandular trichomes. All three mirid predators easily climbed the sticky stems of both tomato lines and found eggs of T. absoluta on leaflets located on the top of the plants. Predation rates, grooming, probing, and feeding activities and the time spent by the three mirid predators until prey encounter were not influenced by a difference in density of trichomes on the two tomato lines. However, E. varians walked longer on TOM 584, and spent more time grooming than M. basicornis. Macrolophus basicornis walked longer on TOM 687. Our results show that the three mirid predators are apparently specialists of glandular plants, because differences in trichome density do not influence their activities, including their prey finding efficiency.