Table 3. Genetic correlations between secondary traits and grain yield.

Environment	DTHD correction	Secondary Traits
		CT-GF	CT-VEG	GNDVI-GF	GNDVI-VEG	RNDVI-GF	RNDVI-VEG
Optimal	Uncorrected	−0.65	−0.5	0.27	0.38	0.33	0.33
	Corrected	−0.63	−0.49	0.24	0.44	0.33	0.35
Drought	Uncorrected	−0.59	−0.53	−0.29	−0.41	−0.12	−0.43
	Corrected	−0.59	−0.51	−0.06	−0.23	0.03	−0.42
Severe drought	Uncorrected	−0.41	0.01	−0.54	−0.62	−0.4	−0.77
	Corrected	−0.4	0.03	−0.46	−0.46	−0.33	−0.73
Late heat	Uncorrected	−0.73	−0.66	0.44	−0.14	0.34	0.47
	Corrected	−0.73	−0.65	0.54	−0.13	0.39	0.51
Early heat	Uncorrected	−0.7	−0.71	0.71	0.61	0.73	0.67
	Corrected	−0.7	−0.72	0.68	0.58	0.71	0.67

Values ≥ |0.09| are significant at the 0.05 level of significance. DTHD, Days to heading; CT, Canopy temperature; GNDVI, Normalized difference vegetation index based on the difference between near-infrared and green light reflectance; GY, Grain yield; RDNVI, Normalized difference vegetation index based on the difference between near-infrared and red reflectance; GF, Grain filling; VEG, Vegetative.