Table 3.

Mean WUE and the ANOVA summary for maize-pea intercropping.

WUE and effecta	Maize			Pea
	2009	2010	2011	2009	2010	2011
Mean WUE (kg ha−1 mm−1)
Plastic barrier	10.9	11.7	11.7	5.5	5.7	5.8
No barrier	13.9	14.2	14.1	5.4	5.7	5.8
Deficit	10.9	11.6	11.2	5.4	5.5	5.8
Sub-optimal	13.4	14.1	13.8	5.6	5.9	5.9
Optimal	12.8	13.1	13.7	5.3	5.7	5.7
Significance at P < 0.05
Root barrier effect
P-value	0.018	0.013	0.008	0.834	0.798	0.818
LSD (0.05)	1.4	1.3	1.1	0.4	0.5	0.4
Water availability effect
P-value	0.021	0.011	0.016	0.704	0.601	0.792
LSD (0.05)	1.3	1.5	1.2	0.5	0.6	0.4
R × W	NSb	NS	NS	NS	NS	NS

Two contrasting root barrier treatments were compared under three water availability levels at Wuwei Experimental Station, 2009–2011.

^aNo significant interaction was found between root barrier treatment and water availabilities for the trait at the p = 0.05 level.

^bNS refers to no significant differences between treatments at 0.05 levels.