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. Solanum L., L L. , L.) species However TOM lineage underexplored interest 1 2 obtained experiment design Additionally acylsugars leaflets Promisingly 131 13 13_ Moreover levels line Tuta 1917 Liriomyza Blanchard. Blanchard . Blanchard) Furthermore responses variety tomatoes 191 19

Abstract Tomato cultivation is globally significant, demanding enhanced yields and biotic stress resilience for sustainability. Dwarf plant utilization in tomato genetic enhancement offers underexplored benefits. Yet, Santa Cruz dwarf tomato germplasm is unavailable. This study evaluated genetic dissimilarity, agronomic potential, and acylsugar content of Santa Cruz dwarf tomato plants across three successive backcrossings. Twelve advanced backcrossing populations (BC) and a commercial control (cv. Kada) were assessed, totaling 15 treatments. Agronomic traits and acylsugar content were measured, and analysis techniques were applied to assess genetic dissimilarity and backcrossing superiority. BC3 populations UFU-Sci#8, UFU-Sci#6, UFU-Sci#5, and UFU-Sci#1 excelled. Dwarf plants predominantly exhibited high leaflet acylsugar levels, suggesting potential for acquisition of hybrid with pest resistance. Notably, UFU MC TOM1 (dwarf plant) displayed significant glycine and L-serine presence, associated with various biotic stresses. These findings unveil the promising creation of dwarf Santa Cruz tomato hybrids with a broad spectrum of resistance. sustainability benefits Yet unavailable backcrossings BC (BC cv. cv (cv Kada assessed 1 treatments measured superiority UFUSci#8, UFUSci8 UFUSci Sci#8, Sci 8 UFU-Sci#8 UFUSci#6, UFUSci6 Sci#6, 6 UFU-Sci#6 UFUSci#5, UFUSci5 Sci#5, 5 UFU-Sci#5 UFUSci#1 UFUSci1 Sci#1 UFU-Sci# excelled levels resistance Notably TOM Lserine L serine presence stresses UFUSci#8 Sci8 Sci#8 UFUSci#6 Sci6 Sci#6 UFUSci#5 Sci5 Sci#5 UFUSci# Sci1 Sci# UFU-Sci

Resumo: Semente de estilosantes (Stylosanthes humilis H.B.K.) é conhecida por apresentar tegumento rijo e quando recém colhida também exibe dormência fisiológica, entretanto, a natureza da coação entre o tegumento e o crescimento do embrião que determina a sua dormência é pouco conhecida. Nesse estudo, a dormência física de sementes de estilosantes não foi reduzida durante o envelhecimento natural à temperatura ambiente, em contraste com a dormência fisiológica que foi superada gradualmente durante o envelhecimento pós-colheita. Além disso, a permeabilidade do tegumento foi afetada por tratamentos de escarificação bem como por soluções de baixo pH. Juntos, esses resultados indicam que a superação da dormência física da semente é um pré-requisito para a protrusão da radícula e a dormência fisiológica das sementes de estilosantes contribui para temporização da germinação.

Abstract: Seed of Townsville stylo (Stylosanthes humilis H.B.K.) is known to exhibit a hard seed coat and when freshly harvested also show a physiological dormancy, however, the nature of the co-actions between seed coat and embryo growth that determine dormancy is poorly understood. In this study, physical dormancy of Townsville stylo seeds was not reduced during natural ageing at room temperature, in contrast to the physiological dormancy, which is gradually overcome during after-ripening. Furthermore, the permeability of seed coat was affected by scarification treatments as well as by low-pH solutions. Together, these data indicate that physical dormancy overcome of seed is prerequisite for radicle protrusion and physiological dormancy of Townsville stylo seeds contribute to its timing.