Table 1.

Trait descriptions, trait heritabilities (h²), and trait correlations between trials. Listed are the 15 traits measured in the BMWpop over three trials, conducted in the United Kingdom in 2017 (UK17) and 2018 (UK18), and in Germany in 2018 (DE18)

Trait code	Trait name	UK17 h2	UK18 h2	DE18 h2	Max. h2 difference	Corr. UK17 vs. UK18	Corr. UK17 vs. DE18	Corr. UK18 vs. DE18
EL	Ear length (cm)	0.77	0.75	0.86	0.11	0.71	0.74	0.80
EW	Ear weight (g)	0.60	0.69	0.80	0.20	0.65	0.29	0.22
NFSP	No. fertile spikelets per ear	0.77	0.66	0.85	0.19	0.71	0.74	0.70
NISP	No. infertile spikelets per ear	0.57	0.57	0.78	0.21	0.35	0.43	0.14
totNSP	Total no. spikelets per ear	0.85	0.70	0.81	0.15	0.76	0.83	0.76
NS.NE	Number of seeds per ear	0.65	0.46	0.85	0.39	0.42	0.45	0.26
WS.EW	Seed weight/ear weight ratio	0.42	0.84	0.62	0.42	0.11	0.16	0.04
SA	Seed area (mm2)	0.77	0.85	0.91	0.14	0.67	0.53	0.47
SWI	Seed width (mm)	0.71	0.83	0.84	0.13	0.6	0.45	0.36
SL	Seed length (mm)	0.84	0.89	0.69	0.20	0.73	0.60	0.49
FFD	Factor form density	0.72	0.77	0.75	0.05	0.61	0.40	0.33
SL.SWI	Seed length/seed width ratio	0.78	0.89	0.95	0.17	0.66	0.66	0.53
FT	Flowering time (days)	0.82	0.63	0.88	0.25	0.73	0.76	0.74
HT	Plant height (cm)	0.83	0.77	0.93	0.16	0.68	0.60	0.74
TGW	Thousand grain weight (g)	0.74	0.61	0.93	0.32	0.66	0.49	0.46
Mean		0.72	0.73	0.83	0.21	0.60	0.54	0.47

All-by-all trait correlations are listed in Supplementary Table 5