The tomato leafminer, Tuta absoluta Meyrick (Lepidoptera: Gelechiidae), is a widespread devastating pest reported to develop on economically important solanaceous crops. The characterisation of its host range could help to understand and prevent the dispersion behaviour of the insect in the environment. In this study, the ability of T. absoluta to develop on 12 cultivated or non-cultivated plants including Solanaceae, Amaranthaceae, Convolvulaceae, Fabaceae, and Malvaceae species under laboratory conditions was assessed. For each plant species, we monitored the development times of immature stages, survival, sex ratios, and adult fecundity rates. All the six tested non-solanaceous plants, including Chenopodium Linnaeus (Amaranthaceae), Convolvulus Linnaeus (Convolvulaceae), and Malva Linnaeus (Malvaceae) species, were not able to sustain (i.e., allow growth and development) T. absoluta larvae. Solanum Linnaeus (Solanaceae) species were the most suitable host plants for the pest, but others could be opportunistically colonised with fewer incidences. Tuta absoluta appears to be strongly related to solanaceous plants that would predominantly support self-sustaining field populations. Preventing crop infestation by removing potential host plants in the immediate field vicinity and culture rotations with non-solanaceous crops is of primary importance.

The development of the infection organ of the parasitic angiosperm genus Cuscuta is a dynamic process that is normally obscured from view as it happens endophytically in its host. We artificially induced haustoriogenesis in Cuscuta campestris by far‐red light to define specific morphologically different stages and analyze their transcriptional patterns. This information enabled us to extract sets of high‐confidence housekeeping and marker genes for the different stages, validated in a natural infection setting on a compatible host. This study provides a framework for more reproducible investigations of haustoriogenesis and the processes governing host–parasite interactions in shoot parasites, with C. campestris as a model species.