Grain Yield and Nitrogen Uptake of Maize (Zea mays L.) as Affected by Soil Management Practices and Their Interaction on Cambisols and Chernozem

Table 7

Pearson’s correlation coefficients for NDVI, grain yield, N-content, N-uptake, and grain protein content of maize grown with two tillage methods, two cropping systems, and four nitrogen levels at Hawassa Zuria (upper right side) and Meskan (lower left side).

	NDVI	GY	GNC	GNU	GPC
NDVI	1	0.59	0.32^ns	0.46^ns	0.33^ns
GY	0.84	1.	0.71	0.89	0.71
GNC	0.73	0.73	1	0.95	0.99
GNU	0.85	0.95	0.90	1	0.95
GPC	0.74	0.74	0.99	0.91	1

Significant at  < 0.05,  < 0.01, and  < 0.001; ns: not significant. NDVI: normalized vegetation index; GY: grain yield; GNC: grain N-content; GNU: grain nitrogen uptake; GPC: grain protein content.