Table 4.

Fraction of total phenotypic variance of physiological drought tolerance-related traits (and flowering time) accounted for within and among populations in B. distachyon (diploid) and B. hybridum (allotetraploid) accessions sampled across the Iberian Peninsula and grown under two different watering treatments. Variance components are standardized to sum to one. Variance components significantly different from zero (P < 0.05) are in bold.

Well watered	Diploids			Allotetraploids
Traits	Vline	Vpop	Vres	Vline	Vpop	Vres
A (µmol CO2 m−2s−1)	0	0.194	0.805	0.085	0.189	0.725
gs (mmol m−2s1)	0.041	0.328	0.631	0.106	0.281	0.642
Integrated WUE (δ13C ‰)	0	0.468	0.532	0.279	0.086	0.625
Flowering time (days)	0.177	0.704	0.118	0.164	0.603	0.231
Water restricted
A (µmol CO2 m−2s−1)	0.107	0.125	0.768	0.091	0.203	0.706
gs (mmol m−2s1)	0.021	0.13*	0.848	0	0.19	0.81
Integrated WUE (δ13C ‰)	0	0.347	0.653	0.187	0.143	0.67
Flowering time (n° days)	0.247	0.478	0.274	0.473	0.213	0.313

^*P<0.1