Radish ( Raphanus sativus L.), a representative of the Brassicaceae family, is an extensively cultivated root vegetable across the world. Thermal time (TT), hydro time (HT), and hydrothermal time (HTT) models can be used to characterize the response of seed germination rate to temperature (T) and water potential ( ψ ). The germination behavior of radish was investigated throughout a range of constant temperatures and water pot...