ORIGINAL ARTICLE • Rev. bras. eng. agríc. ambient. 30 (7) • 2026 • https://doi.org/10.1590/1807-1929/agriambi.v30n7e299732 linkcopy Ponto de inflexão no aparecimento de folhas de genótipos de girassol de corte: uma abordagem bilinear para filocrono HIGHLIGHTS: Cut sunflower exhibits two distinct phyllochron phases: an early phase (V1-V6) and a late phase (V7 to final leaf number). The shift in phyllochron coincides with changes in phyllotaxy and the onset of stem elongation.