Figure 1.

Variation of photosynthesis (P_N; μmol CO₂ m^–2 s^–1) in sugarcane leaves after the application of PSAP (0, 2, 4, 6, and 10 M) under normal irrigation in the Skewed and Gaussian models. Data are represented as the arithmetic mean (n = 3). Blue ovals denote the observed values and red lines show the calculated values. Parenthesis values indicate percent deviation. (A–E) Skewed model, (a–e) Gaussian model, S = standard error, and r = correlation coefficient.