Calcium (⁴⁵CA²⁺) absorption by sorghum seedling roots after exposure to PCMBS and three cation channel blockers

Abstract

Root‐tips, 1‐cm, of Sorghum bicolor (L.) Moench cv SC283, SC574, GP‐10, and Funk G522DR were exposed to 1 mM PCMBS for 10‐min and then to ⁴⁵Ca²⁺ in the presence of cation channel blockers nifedipine (0, 0.001, 0.01, 0.1, or 1.0 μM), diltiazem (0, 0.001, 0.01, 0.1, 1.0, or 10.0 mM), or verapamil (0, 0.01, 0.1, 1.0, or 10.0 mM)] at pH 5.5 for 2‐hr. Significant differences in total ⁴⁵Ca²⁺ absorption between cultivars without cation channel‐blockers was observed. Each channel‐blocker was effective at concentrations that were interactions of channel‐blocker and cultivar.