Figure 10.

Root transcript levels of two putative AMT ${\text{NH}}_4^{+}$ transporters (A,B) in diverse maize genotypes grown in nutrient solution containing either 0.5 mM (open bars) or 2.5 mM (closed bars) ${\text{NO}}_3^{-}$. Each data point is normalized against control genes (ZmGaPDh, ZmActin, ZmTubulin, and ZmElF1). Values are means ± SEM (n = 4), ^* indicates those points that are significantly different between the two growth conditions at 0.05 significance level. Genotypes are ordered from left to right according to their ability to retain biomass as shown in Figure 2.