Using Sigmoid Growth Curves to Establish Growth Models of Tomato and Eggplant Stems Suitable for Grafting in Subtropical Countries

In subtropical regions, tomato (Solanum lycopersicum) is mainly produced in autumn and winter. To enhance the off-season production of tomato, summer cultivation has become a prime objective. Grafting scions onto eggplant melongena) rootstocks key method to overcome difficulties summer. this study, we collected seedling growth data over six growing seasons Taiwan established models by employing three commonly used sigmoid curves, namely Gompertz, Richards, Logistic curves. Cumulative temperature was introduced as an independent variable its relationship with plant stem diameter determined. The R2 values were 0.74–0.85 0.72–0.80 calibration validation, respectively. Performance did not differ markedly among same season, but notable differences observed for different seasons. addition, estimates several model parameters differed significantly seasons; hence, separate should be results study can prediction arrangement grafting schedule improve efficiency countries.