How bottom-up effects of different tomato cultivars affect population responses of Tuta absoluta (Lep.: Gelechiidae): a case study on host plant resistance

Abstract

The Gellechiid moth, Tuta absoluta (Meyrick), causes severe problems in many tomato-growing regions worldwide. The present study investigated bottom-up effects under laboratory conditions (25 ± 1 °C, 65 ± 5% R.H., and 16 h L.P.) of six commercial tomato cultivars (‘Rio grand’, ‘Atrak’, ‘Super strain B’, ‘Unigen’, ‘King ston’, and ‘Estern’) on biological traits of this pest. The results obtained evaluated with age-stage, two-sex life table. Duration of different life stages and adult fecundity of this pest were strongly affected by cultivars tested. The highest and lowest mortality of pre-adult stages were estimated on the ‘Atrak’ (36 ± 5%) and ‘King ston’ (15 ± 3%), respectively. Tomato cultivars significantly affected population parameters of T. absoluta. The net reproductive rate (R0) was highest on the ‘King ston’ (97 ± 11.8 offspring/individual). The finite (λ) and intrinsic (r) rates of population increase were dramatically lower on the cultivar ‘Atrak’. Under laboratory conditions, the cultivars ‘Atrak’ and ‘King ston’ had the highest and least resistance level to this pest, respectively. Host plant resistance will be foundational to developing integrated pest management programs.