Calcium-dependent transcriptional responses of Arabidopsis leaves and roots of hydroponically-grown plants. qPCR performed on RNA isolated from the (A) shoots and (B) roots (above and below the hypocotyls, respectively) of 5-week old Arabidopsis KC464 plants grown under three different Ca activities (aCa LCS = 0.025mM; aCa BNS = 1 mM; aCa HCS = 5 mM) for seven days. n = 9, from three biological replicates per tissue. Mean + SD. Asterisk indicates significant expression difference from BNS (P < 0.01). qPCR performed as described in Conn et al. [19, 20] with primers listed in Additional file 3.