Table 2. Results of exponential models for three fungi growth of R. stoloifenr, B. cinerea and C. acutatum^*.

Fungal species	Method	Simulation equation	Calibration dataset			Testing dataset			r
			Rc 2	SSE(×10−4)	RMSE	Rp 2	SSE(×10−4)	RMSE
B. cinerea	I	$f(x)=0.124+\frac{1}{49603.352*e^{-0.18x}+6.81}$	0.9959	0.99	0.007	0.7223	53.40	0.023	0.898
	II	$f(x)=0.178+\frac{1}{77800*e^{-0.195x}+3.92}$	0.9948	3.79	0.011	0.7910	3.34	0.057	0.941
	III	$f(x)=-\text{0}.\text{685}+\frac{1}{141.1*e^{-0.141x}+0.265}$	0.9979	334.00	0.106	0.7897	4.65	0.254	0.932
C. acutatum	I	$f(x)=0.124+\frac{0.064}{9070*e^{-0.325x}+0.578}$	0.9903	1.67	0.025	0.9367	8.77	0.756	0.899
	II	$f(x)=0.178+\frac{0.092}{9096*e^{-0.326x}+0.589}$	0.9939	1.48	0.014	0.9368	7.74	0.044	0.900
	III	$f(x)=-0.879+\frac{1}{604.3*e^{-0.219x}+0.463}$	0.9813	682.00	0.261	0.8687	14.80	0.504	0.887
R. stoloifenr	I	$f(x)=0.111+\frac{1}{117.55\times e^{-0.237x}+1.589}$	0.9996	1.23	0.013	0.9815	3.76	0.019	0.954
	II	$f(x)=0.158+\frac{1}{80.15*e^{-0.236x}+1.202}$	0.9960	2.48	0.016	0.9914	2.03	0.011	0.957
	III	$f(x)=-1.443+\frac{1}{27.74\times e^{-0.232x}+0.415}$	0.9996	18.20	0.043	0.9906	3.32	0.129	0.955

*I, II and III represented the different methods I, the average of full spectrum in the range of 400–1000 nm; II, the response value at wave crest of 716 nm; III, the value of principal component score of the full spectrum. R_c ² and R_p ² were the coefficient of determination of calibration and prediction, respectively; SSE and RSE, sum of squares due to error and root mean squared error, respectively; r, the correlation coefficient of prediction accuracy between spectral values and colony forming unit.