The Study of Seed Germination and Seedling Growth of Balangu (Lallemantia royleana ‎‎(Benth.) Benth.in Wall) in Response to Temperature and Quantification of Cardinal ‎Temperatures Using Nonlinear Regression Models

In this research, biological characteristics of Balangu seed in response to temperature were evaluated. Germination responses and cardinal temperatures were evaluated using dent-like, segmented, beta and quadratic regression models and regression coefficients (a and b), correlation of determinant (R2), correlation coefficient (r), and significant level functions of predicted values versus observed ones were used to find the appropriate models. The results showed that the germination of Balangu is possible at a range of 5 to 25 °C. The highest germination percentage was detected at 20°C (98.5%). Moreover, at 20°C temperature the highest seedling growth and less time to shoot emergence (60.03 mm and 58 h respectively) was detected. Segmented model was superior compared to other models, therefore, this model is recommended for quantifying biological parameters and seedling emergence of Balangu. Temperatures of 1°C, 22.6°C and 30°C were the cardinal temperatures for seed germination (minimum, optimum and maximum, respectively). According to the results of this research, Balangu is the psychrophile plants and appropriate temperature germination is 20°C to 22.6°C. In this research, a proposed equation entitled of "Germination Value (GV)" for the simultaneous evaluation of seed germination and seedling growth per unit of time was introduced.