The role of calcium channels in anthocyanin production in callus cultures of Daucus carota

The involvement of Ca²⁺ ATPases in anthocyanin accumulation in callus cultures of Daucus carota was investigated under the influence of calcium and calcium channel modulators. Ionophore (I) treatment enhanced callus growth and anthocyanin accumulation. Increasing the amount of calcium applied to cultures enhanced the anthocyanin level. Ionophore treatment influenced the enhancement of Ca²⁺ATPase and endogenous titres of PAs. Addition of the calcium channel blocker verapamil or the calmodulin antagonist chlorpromazine to the A23187 (ionophore) treated cells caused a reduction in anthocyanin levels. Channel blockers reduced Ca²⁺ATPase activity, which was restored by ionophore treatment, showing the importance of calcium in anthocyanin production. Higher ethylene levels were also found in treatment with ionophore or 2X calcium. Thus the influence of ionophore in anthocyanin production and its inhibition by calcium channel modulators suggests that calcium plays an important role in the production of anthocyanin by carrot callus cultures.