Diverse range of fitnesses by ovipositing and feeding on fifteen eggplant genotypes in tomato leafminer, Tuta absoluta (Lepidoptera: Gelechiidae)

Tomato leafminer, Tuta absoluta has invaded Iran in recent years and rapidly turned into an important pest of tomato crops in open fields and greenhouses. Tomato is the preferred host of the pest. However, preliminary observations have shown that it can feed and reproduce on the other Solanaceous crops like eggplant and potato. In his study, the fitness of tomato leafminer has been investigated on fifteen commonly cultivated eggplant genotypes including Ghasri Dezful, Paboland Yazd, Mahali Jahrom, Shendabad, Dastgerd Esfahan, Sarkhoun Bandarabas, Chahboland Neishabur, Ghalami Varamin, Black Beauty, Blacky, Yalda, Lady, Linda, Lima and Kime in a greenhouse with the mean daily temperature of 25 ± 2°C, 60 ± 5% Relative Humidity and a natural photoperiod during the May and June. The ovipositional preference of females and some biological parameters like development times and survival rates of egg, larva and pupa, pupal weight and sex ratio have been evaluated on the plant genotypes using free-choice and no-choice tests. Significant differences have been revealed in the number of daily oviposited eggs on both potted plants and excised leaves and in all biological parameters except pupal weight and sex ratio among the eggplant genotypes throughout the experiments. The ovipositional preference of the females was significantly correlated and negatively correlated respectively with chlorophyll content of the leaves of eggplant genotypes (P < 0.01) and with trichome density on the underside of the entire leaf surface (P < 0.05). The eggplant genotypes were clustered into three main categories of resistant (Kime), semi-resistant (Black Beauty and Blacky) and semi-susceptible (other genotypes) using Ward-1963 hierarchical clustering method. The observed differences among the examined genotypes can be used in cropping systems for designing of eggplant breeding and tomato leafminer management programs.