highly significantP < 0.01
S = 96.99 − 2.77 A + 2.51 B − 0.87 C + 1.08 A B − 0.86 A C + 1.15 B C − 1.17 A 2 − 0.59 B 2 − 1.46 C 2 (17) D = 5.30 − 0.39 A + 1.00 B − 2.52 C + 0.25 A B − 0.040 A C + 0.47 B C − 1.09 A 2 − 0.26 B 2 + 0.79 C 2 (18) Table 3 shows that the two regression models were highly significant ( P < 0.01), and the fitting degrees of the regression equations were high ( P > 0.05).