The effectiveness of natural enemies is evaluated through life table experiments and analyses of foraging behavior, including functional responses that quantify their predation capacity in relation to prey density. The age- and stage-dependent functional response and predation capacity of Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae) on eggs of the tomato leaf miner Phthorimaea absoluta (Meyrick) (Lepidoptera: Gelechiidae) were evaluated under laboratory conditions using tomato leaf discs. Prey densities of 2, 4, 8, 16, 32, 64, and 128 eggs were offered to N. tenuis individuals aged 8 (nymph I), 11 (nymph II), 14 (nymph III), 16 (nymph IV), 19 (nymph V), 24 (3-day-old adult female), and 26 (5-day-old adult female) days. The functional response of 24- and 26-day-old individuals corresponded to a Type III pattern, whereas earlier developmental stages exhibited a Type II response. The longest handling time (0.70 h) was recorded for 11-day-old nymphs, while the shortest handling time (0.24 h), the highest estimated maximum predation rate (T/Th = 98.73 prey/day), and the highest mean observed maximum predation rate (89.4 prey/day) were obtained from 26-day-old adults. At the highest prey density (128 eggs), 19-, 24-, and 26-day-old individuals consumed an average of 75.33, 55.00, and 83.00 eggs per day, respectively. Overall, N. tenuis, particularly at the final nymphal and adult stages, demonstrates strong predation potential against P. absoluta eggs at higher prey densities, highlighting its value as an effective biological control agent.
Zangiabadi et al. (Tue,) studied this question.