Analyzing protein concentration from intact wheat caryopsis using hyperspectral reflectance

Chemical and Biological Technologies in Agriculture

Table 2 Estimated model performance of winter wheat grain protein under different spectral pretreatment

Sample types	Spectrum types	Models	Pretreatment methods	Calibration set			Validation set
Sample types	Spectrum types	Models	Pretreatment methods	R²	RMSE	RPD	R²	RMSE	RPD
Grain	Full spectra	BPNN	FD	0.796	0.027	2.215	0.739	0.034	1.956
		PLS	FD	0.832	0.022	2.437	0.764	0.026	2.058
		RF	SG	0.929	0.014	3.766	0.779	0.026	2.125
		SVM	FD	0.783	0.025	2.149	0.778	0.026	2.123
	Sensitive wavebands	BPNN	MSC	0.777	0.025	2.119	0.671	0.032	1.743
		PLS	SNV	0.754	0.027	2.016	0.714	0.029	1.871
		RF	SG	0.848	0.021	2.567	0.746	0.028	1.983
		SVM	SG	0.773	0.025	2.097	0.789	0.026	2.177
Powder	Full spectra	BPNN	SG	0.881	0.018	2.894	0.735	0.027	1.941
		PLS	SNV	0.901	1.643	3.172	0.727	0.027	1.915
		RF	FD	0.965	0.001	5.356	0.803	0.024	2.254
		SVM	FD	0.87	0.019	2.77	0.766	0.024	2.068
	Sensitive wavebands	BPNN	SG	0.851	0.021	2.594	0.814	0.024	2.318
		PLS	MSC	0.873	0.019	2.805	0.797	0.023	2.218
		RF	FD	0.935	0.013	3.923	0.777	0.025	2.118
		SVM	FD	0.864	0.019	2.71	0.789	0.023	2.176