Uptake of labelled phosphorus by rooted and non‐rooted in vitro cultured ‘John Franklin’ rose

Abstract

Plantlets of the winter‐hardy ‘John Franklin’ rose cultivar, derived from nodal sections of greenhouse‐grown plants, were cultured on a modified MS medium. The kinetics of P uptake for 96 h as a function of medium temperature was studied by using ³²P. Rooted plantlets absorbed significantly (P < 0.01) greater amounts of P at 22°C compared with non‐rooted ones and uptake was linear with time for both. P uptake was also significantly higher (P < 0.05) for rooted versus non‐rooted plantlets at 33°C but no significant difference was observed at 3°C. The results show that roots, previously thought to be mostly non‐functional in nutrient uptake on a culture medium, played a key role in absorbing P at 22 and 33°C.

Notes

Agriculture Canada, Research Branch, P.O. Box 3398, 801 Route 344, L'Assomption, Quebec, Canada J0K 1G0