Can alternative host plant and prey affect phytophagy and biological control by the zoophytophagous mirid Nesidiocoris tenuis?

Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae) is an important natural enemy of several key arthropod pests. However, in tomato crop this predator can cause economic damage owing to its zoophytophagous behavior. We investigated in laboratory conditions the influence of two alternative plants, Dittrichia viscosa L. (Asteraceae) and Sesamum indicum (L.) (Pedaliaceae), with or without prey, on N. tenuis damage and its biological control services on Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) eggs. Both D. viscosa and S. indicum, as companion plants in dual-choice bioassays, significantly reduced the damage of the mirid on tomato. S. indicum was more attractive than D. viscosa for feeding and oviposition and its presence did not interfere with the predation on T. absoluta eggs. We also studied the potential of the three plants as preyless rearing substrate for the mirid, and only S. indicum showed to be a suitable host plant for N. tenuis development and oviposition. The potential applications of S. indicum in N. tenuis field management and mass rearing are discussed.