Biological traits of the predatory mirid Macrolophus praeclarus, a candidate biocontrol agent for the Neotropical region

Abstract

The predatory mirid Macrolophus praeclarus is widely distributed throughout the Americas, and is reported to prey upon several horticultural pest species. However, little is known about its biology, thermal requirements, crop odour preferences, phytophagy, and capability to induce defensive responses in plants. When five temperatures studied (20, 25, 30, 33 and 35°C) were tested and Ephestia kuehniella was used as prey, the developmental time from egg to adult on tomato, was longest at 20°C (56.3 d) and shortest at 33°C (22.7 d). The ability of nymphs to develop to adults decreased as the temperature increased, with the highest number of nymphs reaching the adult stage at 20°C (78.0%) and lowest at 35°C (0%). The lower and upper developmental thresholds were estimated at 11.2° and 35.3°C, respectively. The maximum developmental rate occurred at 31.7°C and the thermal constant was 454.0 ± 8.1 degree days. The highest predation rate of E. kuehniella eggs was obtained at 30°C. In Y-tube olfactory choice tests, M. praeclarus selected tomato, sweet pepper and eggplant odours more frequently than no plant control treatment. Macrolophus praeclarus feeding did not damage tomato plants compared to another zoophytophagous mirid, Nesidiocoris tenuis, which caused necrotic rings. The phytophagy of M. praeclarus induced defensive responses in tomato plants through the upregulation of the jasmonic acid metabolic pathway. The implications of the findings for using M. praeclarus in tomato biological control programmes in the Americas are discussed.

Half Friend, Half Enemy? Comparative Phytophagy between Two Dicyphini Species (Hemiptera: Miridae)

“…Phytophagous behaviour in N. tenuis is regarded as more severe than in other dicyphine mirids [6,17,18] since this species has the particularity to feed on vascular tissues and to aggregate on feeding sites [29]. Our study corroborates this, as plants with N. tenuis suffered more damage than those with D. cerastii.…”

“…Phytophagous behaviour in N. tenuis is regarded as more severe than in other dicyphine mirids [6,17,18] since this species has the particularity to feed on vascular tissues…”

“…Plant damage can greatly vary with host plant species [6], mirid species [6,17,18], and even among populations of the same species [19,20]. Therefore, understanding the risk that phytophagy represents to crops is a key point in the evaluation of a new candidate BCA [13], such as D. cerastii, that will help decision making while choosing the best suited mirid species.…”

Induction of plant defenses: the added value of zoophytophagous predators

“…This could be the case of Macrolophus praeclarus (Distant), a polyphagous mirid predator recently reported as highly effective in the control of B. tabaci (Roda et al 2020). The phytophagy of M. praeclarus also induces defensive responses in tomato plants through the upregulation of the JA pathway (Pérez-Hedo et al 2021c). Further studies should elucidate the biological effect of M. praeclarus-induced defenses on key tomato pests.…”

Integrated pest management of Tuta absoluta: practical implementations across different world regions

“…Nevertheless, the two commercially available predatory mirid bugs, N. tenuis and M. pygmaeus, have emerged as key biological control agents for T. absoluta in Europe (Pérez-Hedo et al 2021a). The success obtained with the use of mirids in European tomatoes has prompted other geographical regions, mainly in the American continent, to study the pest control application of native mirids (Pérez-Hedo et al 2021b;Roda et al 2020). The effectiveness of mirid predators such as N. tenuis and M. pygmaeus can be attributed to i) their voracious consumption of T. absoluta eggs (Arno et al 2009;Urbaneja et al 2009;Sylla et al 2016) and ii) their zoo-phytophagous feeding habit, which allows them to subsist on tomato plants during periods of prey scarcity (Thomine et al 2020;Pérez-Hedo et al 2021a).…”