Table 4.

Result of an analysis of covariance on the effect of population and the covariate cumulative VPD (cum_vpd) on drought tolerance DRYMp.

Model	Type	Source	df	F	p
1	pot	error	1096
1	pot	population	6	8.3	<0.0001
1	pot	cum_vpd	1	48.1	<0.0001
1	big-bag	error	1207
1	big-bag	population	6	3.9	0.0007
1	big-bag	cum_vpd	1	28.0	<0.0001
1	field	error	1195
1	field	population	6	2.4	0.0265
1	field	cum_vpd	1	12.2	0.0005
2	pot	error	1057
2	pot	population	3	13.2	<0.0001
2	pot	cum_vpd	1	51.1	<0.0001
2	big-bag	error	1156
2	big-bag	population	3	5.7	0.0007
2	big-bag	cum_vpd	1	29.7	<0.0001
2	field	error	1151
2	field	population	3	3.8	0.0106
2	field	cum_vpd	1	12.8	0.0004

In Model 1, the factor population contains the three subpopulations, the parents, and the population G2 without the lines that were selected into the subpopulations. Model 2 does not contain the data on the parents.