Relationship of Maize Yield to Climatic and Environmental Factors under Deficit Irrigation: A Quantitative Review

Table 2

Multiple linear regression model of GY_V and IWUE_V for different growth stages.

Sources of variation	GYV		IWUEV
	Estimates	Standard error	Estimates	Std error
Vegetative stage
Intercept	−4.16	3.60	−11.98	4.12^∗∗
Water deficit percentage	0.86	0.12^∗∗∗	1.42	0.21^∗∗∗
Nitrogen rate	0.0005	0.018	0.006	0.015
Adjusted R^2	0.59		0.57
Multiple R^2	0.62		0.60
P value	<0.001		<0.001
Reproductive stage
Intercept	6.77	5.78	−14.50	9.80
Water deficit percentage	0.45	0.11^∗∗∗	0.68	0.18^∗∗∗
Nitrogen rates	0.02	0.02	−0.02	0.03
Adjusted R^2	0.22		0.21
Multiple R^2	0.54		0.24
P value	<0.001		<0.001
Vegetative and reproductive stage
Intercept	12.67	5.89^∗	−18.81	16.12
Water deficit percentage	0.32	0.11^∗∗	0.66	0.29^∗
Nitrogen rates	0.02	0.02	0.11	0.05^∗
Adjusted R^2	0.10	0.09
Multiple R^2	0.13		0.12
P value	0.016		0.03

^∗∗∗p<0.001, ^∗∗p<0.01, and ^∗p<0.05.