Table 5.

Correlation between canopy vegetation index NDVI, GNDVI, RVI, GOSAVI, and leaf nitrogen content in maize at different growth stages

Stage	Cultivar	NDVI	GNDVI	RVI	GOSAVI
Trumpet stage	ZD958	0.827**	0.808**	0.814**	0.826**
	XY335	0.820**	0.871**	0.653**	0.860**
	YD606	0.647**	0.882**	0.551*	0.918**
	QL368	0.513	0.704**	0.532*	0.704**
	Mixture	0.611**	0.770**	0.580**	0.775**
Filling stage	ZD958	0.908**	0.939**	0.960**	0.939**
	XY335	0.853**	0.877**	0.851**	0.874**
	YD606	0.979**	0.958**	0.931**	0.957**
	QL368	0.839**	0.871**	0.909**	0.873**
	Mixture	0.777**	0.869**	0.817**	0.869**
Maturity	ZD958	0.779**	0.777**	0.746**	0.812**
	XY335	0.617*	0.733**	0.650**	0.733**
	YD606	0.567*	0.761**	0.386	0.876**
	QL368	0.418	0.622*	0.301	0.613*
	Mixture	0.124	0.314*	0.160	0.297*

“*” indicates the significance at the 0.05 level. “**” indicates the significance at the 0.01 level.