Table 2.

Heritability of indices averaged by index groups by measurement dates calculated for all measurement dates.

Date	d.a.s.	GDD	Growth stage	Heritability (H²)
				NIR	NIR_VIS	VIS	NIR_RE	NIR_RE_VIS	RE	RE_VIS
2015
150424	171	194	Tillering	0.29	0.29	0.53	0.32	0.16	0.27	0.29
150625	233	782	Late milk	0.39	0.69	0.86	0.61	0.70	0.61	0.73
150707	245	978	Soft dough	0.52	0.66	0.85	0.70	0.75	0.72	0.72
150716	254	1101	Hard dough	0.74	0.78	0.92	0.76	0.76	0.76	0.77
2016
160405	175	200	Leaf development	0.59	0.59	0.64	0.56	0.60	0.61	0.59
160411	181	217	Tillering	0.58	0.64	0.70	0.53	0.52	0.56	0.60
160421	191	254	Tillering	0.77	0.78	0.89	0.59	0.62	0.66	0.75
160518	218	385	Stem elongation	0.81	0.50	0.72	0.64	0.68	0.60	0.64
160529	229	487	Booting	0.91	0.66	0.77	0.86	0.86	0.80	0.80
160610	241	615	Anthesis	0.91	0.86	0.91	0.89	0.90	0.86	0.88
160614	245	655	Early milk	0.91	0.88	0.93	0.84	0.91	0.87	0.91
160623	254	766	Milk	0.85	0.83	0.94	0.89	0.90	0.86	0.89
160628	259	839	Late milk	0.84	0.85	0.94	0.91	0.92	0.90	0.89
160708	269	969.5	Early dough	0.78	0.85	0.93	0.89	0.91	0.87	0.87
160710	271	1001	Soft dough	0.83	0.80	0.94	0.88	0.90	0.83	0.83
160719	280	1116	Hard dough	0.74	0.90	0.92	0.90	0.90	0.88	0.87
2017
170331	159	109	Leaf development	0.77	0.77	0.71	0.74	0.75	0.77	0.77
170413	172	167	Tillering	0.70	0.77	0.81	0.77	0.72	0.77	0.77
170517	206	297	Stem elongation	0.85	0.59	0.66	0.82	0.85	0.81	0.69
170525	214	372	Booting	0.82	0.15	0.43	0.83	0.80	0.72	0.45
170608	228	534	Anthesis	0.94	0.91	0.88	0.93	0.94	0.92	0.87
170614	234	609	Anthesis	0.92	0.40	0.65	0.91	0.87	0.80	0.66
170621	241	706	Milk	0.82	0.33	0.65	0.90	0.86	0.79	0.66
170701	251	862	Early dough	0.86	0.72	0.87	0.90	0.93	0.90	0.83
170705	255	915	Soft dough	0.58	0.89	0.94	0.93	0.95	0.94	0.92
170711	261	1017	Hard dough	0.96	0.96	0.96	0.95	0.95	0.95	0.95

SVIs are grouped according to the included spectral regions (Table 3; Supplementary Figure 1). See Supplementary Table 2 for heritability values by indices. Dates of are listed as year/month/day with days after sowing (d.a.s.) and growing degree days based on a 5°C threshold.