Grain protein content (GPC) variation among 59 cultivated and 99 Tibetan wild barley accessions grouped according to the haplotypes in HvNAM1 (a, b) and HvNAM2 (c, d). The means of GPC in 2009 (a, c) and 2008 (b, d) are shown. Error bars indicate standard deviations.
Cai et al. BMC Plant Biology 2013 13:35 doi:10.1186/1471-2229-13-35