New insights into the use of dwarf tomato plants for pest resistance

ABSTRACT

Tomato (Solanum lycopersicum L.), a globally significant species, faces substantial economic losses due to pest insects. However, exploiting dwarf germplasm for pest resistance, particularly the UFU MC TOM1 lineage, remains underexplored. The objectives of this study were to select backcross populations from dwarf tomato plants through direct and indirect selection and to elucidate whether there are consequences in resistance level as backcross generations progress aiming at a genetic background of interest. Backcross populations 1, 2, and 3 of dwarf tomato plants were obtained. In the conducted experiment, featuring 20 treatments and four repetitions in a randomized block design, we assessed foliar injuries and herbivory through image analysis. Additionally, we quantified the content of acylsugars, conducted chromatographic analysis, and analyzed the metabolomic profile in the leaflets. Promisingly, the UFU 13_1 dwarf plant population showed potential for enhancing genetic improvement programs targeting pest insect resistance. Moreover, the progression of backcross generations yielded varied resistance levels, likely influenced by inheritance patterns and acylsugar content. The UFU MC TOM1 line, distinguished by its high acylsugar content, exhibited robust resistance against both the tomato leafminer (Tuta absoluta Meyrick 1917) and the leafminer (Liriomyza huidobrensis Blanchard). Furthermore, our analysis revealed the expression of metabolites in the UFU MC TOM1 lineage, potentially linked to various biotic and abiotic stress responses. These findings offer promising prospects for leveraging the dwarf tomato variety, UFU MC TOM1, in genetic improvement programs aimed at combating pest insects in tomatoes.

Key words
Solanum lycopersicum L.; Liriomyza huidobrensis ; Tuta absoluta ; pest resistance; backcross populations