Table 2.

Evaluation of different elements partial least squares regression (PLS-R) models.

Element	Explained variance (%)	R2	RMSEC	Q3-Q1	RPIQ
K	75.18	0.74	54.41	329.10	6.05
P	38.68	0.36	16.61	112.09	6.75
Mg	79.44	0.73	13.85	98.43	7.11
Zn	72.86	0.69	0.07	0.38	5.28
S	63.97	0.52	17.55	103.63	5.90
B	41.9	0.42	0.17	1.03	6.15

Each model was built from 40 observations (five replicates from two treatments over four time points), and include six latent variables. Q₃-Q₁, maximal element range between samples; RPIQ, (Q₃-Q₁)/RMSEC. Mineral contents are in mg Kg^-1.