N. Vitta, P. Estay, and Chorbadjian, R.A. 2016. Characterization of resistance expression in genotypes of Solanum Section Lycopersicon against Tuta absoluta (Lepidoptera: Gelechiidae). Cien. Inv. Agr. 43(3):366-373. Two studies were conducted with the aim of characterizing the antixenosis and antibiosis resistance expression of genotypes in the Solanum section Lycopersicon against Tuta absoluta (Meyrick). The species used were S. lycopersicum (Fiorentino, Naomi and Belle), S. habrochaites (RCAT030597, PI126446), S. chilense (INIABB79), S. peruvianum (RCAT031296, RCAT039874 and RCAT030403) and S. pimpinellifolium (PI390739). For the antixenosis bioassay, a leaf was removed from plants of each genotype and placed in a cup with a floral foam soaked in water. The cups were stored in cages covered with anti-aphid mesh. The number of eggs per plant was determined seven days after releasing the adults. For the antibiosis bioassay, one leaf per genotype and replication was placed in a plastic cup with floral foam soaked in water, and first-stage tomato leaf miner larvae were placed individually on the leaves. Larval survival, total average male and female pupal weight and consumed foliar area were assessed for each genotype. It was determined that most wild species showed resistance to Tuta absoluta by antixenosis and antibiosis mechanisms. The genotype S. habrochaites (RCAT030597) presented more resistance by antibiosis based on larval survival. Nonetheless, the resistance-level characterization depended on the insect response that was considered because S. chilense was less preferred for oviposition; however, in this genotype, the larval survival in the no-choice assays was among the highest observed. Thus, this study provides comprehensive information on the resistance level of several Solanum genotypes that could be used in further efforts to understand the complex mechanisms underlying Solanum resistance to the tomato leaf miner.