Table 8. Predication models (the range for original and validation data of agronomic parameters (Par.), R², slope, intercept and RMSE) using support vector machine regression (SVM) for the full wavelength range (350–2500 nm).

Models are based on the calibration data of two years for the green leaf area (GLA), aboveground total dry weight (TDW), grain yield (GY) and water use efficiency (WUE) under individual irrigation rates and plant densities.

	Irrigation rates			Plant densities (D)
Statistics	1.00 ET	0.75 ET	0.50 ET	D1	D2	D3	D4	D5
GLA (cm2 plant-1)
Range of orginal data	315.3–510.4	252.5–377.0	138.9–244.6	178.2–407.9	221.7–461.8	197.0–486.8	152.7–510.4	138.9–432.8
Range of validation	233.0–425.4	251.1–383.7	157.1–355.4	205.5–318.8	246.3–425.4	221.6–405.6	225.3–414.7	157.1–339.43
R2	0.28	0.18	0.19	0.86***	0.86***	0.53*	0.81**	0.89**
Slope	0.45	0.60	0.81	0.51	0.74	0.45	0.53	0.38
Intercept	178.35	123.75	89.54	125.5	87.82	180.1	135.18	145.00
RMSE	93.4	36.04	72.27	45.1	34.49	73.9	64.1	33.2
TDW (g m-2)
Range of orginal data	950.3–2343.3	939.6–1683.4	545.9–1019.4	568.2–1047.2	978.3–1640.9	886.2–2186.0	626.9–2343.3	545.9–1823.6
Range of validation	891.1–1745.3	849.6–1584.4	665.2–1571.4	745.2–1287.1	1063.4–1745.3	924.2–1676.1	993.6–1733.8	665.2–1491.5
R2	0.48*	0.71**	0.26	0.55*	0.91***	0.83***	0.87***	0.93***
Slope	0.39	0.69	0.73	1.16	1.13	0.56	0.42	0.67
Intercept	848.51	375.9	454.4	- 60.92	-42.86	505.20	718.60	365.7
RMSE	389.2	140.2	334.1	259.1	155.9	319.2	406.0	197.7
GY (g m-2)
Range of orginal data	506.3–959.8	479.1–820.4	329.8–501.9	360.7–568.5	501.6–854.4	443.9–952.8	404.0–959.8	329.8–884.3
Range of validation	499.1–864.2	499.1–797.9	369.0–767.7	392.3–652.1	533.2–864.2	475.5–833.2	504.1–852.2	369.0–738.1
R2	0.63**	0.64**	0.34	0.48*	0.77**	0.92***	0.78**	0.96***
Slope	0.51	0.76	1.21	0.93	0.85	0.68	0.52	0.69
Intercept	343.34	111.5	139.6	89.3	104.0	182.0	286.9	156.6
RMSE	151.0	84.6	136.1	86.6	67.7	152.7	129.5	70.7
WUE (g m-2 mm-1)
Range of orginal data	0.86–1.60	1.05–1.79	1.01–1.53	0.86–1.16	1.31–1.63	1.35–1.79	1.23–1.61	1.01–1.48
Range of validation	1.02–1.54	1.02–1.54	1.05–1.49	1.02–1.49	1.40–1.57	1.31–1.57	1.34–1.56	1.15–1.51
R2	0.75**	0.81***	0.70**	0.49*	0.02	0.52*	0.64*	0.84***
Slope	0.78	0.63	0.70	2.86	- 0.11	0.34	0.37	0.67
Intercept	0.33	0.46	0.43	-1.85	1.64	0.96	0.89	0.46
RMSE	0.095	0.14	0.01	0.21	0.12	0.15	0.12	0.089

*, **, *** indicate significance at 0.05, 0.01 and 0.001 P level, respectively. D1, D2, D3, D4, and D5 indicate plant density of 150, 250, 350, 450, and 550 seeds m^-2, respectively.