VITAMIN D IMPROVES CALCIUM UPTAKE INTO MICROPROPAGATED POTATO PLANTLETS

The vitamin D group, including D₂ (ergocalciferol), D₃ (cholecalciferol), and their active metabolites, have been detected in several plant species; mostly within the family Solanaceae.
Vitamin Ds are known to improve calcium (Ca²⁺) uptake in animals and stimulate the calcium-binding protein calmodulin in both animals and plants.
Evidence that vitamin Ds could affect Ca²⁺ uptake was lacking for plants. For this reason, the radioisotope ⁴⁵Ca²⁺ was employed to measure the uptake of calcium into shoots of micropropagated potato plantlets (Solanum tuberosum ‘Russet Burbank’) treated with nutrient solutions containing vitamin Ds (D₂ or D₃ at 0, 10, 25 or 50 mgL^-1) and Ca (3, 5 or 15 mM). Vitamin Ds at 25 mgL^-1 were most effective at improving ⁴⁵Ca²⁺ uptake into plantlet shoots.
At higher concentrations (50 mgL^-1) vitamin D3 did not stimulate ⁴⁵Ca²⁺ uptake beyond that achieved at 25 mgL^-1 and D₂ was inhibitory to uptake.
It was evident from this study that vitamin Ds improved ⁴⁵Ca²⁺ uptake into shoots of micropropagated potato plantlets and that D₃ was more efficient in this capacity than D₂ or a combination of D₂ and D₃. Vitamin Ds apparently play a similar role in both plants and animals by affecting Ca absorption and Ca-mediated cellular functions.

XXVI International Horticultural Congress: Potatoes, Healthy Food for Humanity: International Developments in Breeding, Production, Protection and Utilization

A. Habib, D.J. Donnelly

⁴⁵Ca²⁺, cholecalciferol, ergocalciferol, flame atomic absorption spectometry, liquid scintillation counting, Solanum tuberosum, tissue culture

https://doi.org/10.17660/ActaHortic.2003.619.29