Plastic 12-well plates (Denmark, Nunc) Note: One for the absorption step, one for the desorption step for each treatment (plant type or culture condition).
Plastic 20 ml vials for radioactivity measurement (Ratiolab GmbH, Dreieich) Note: You will need one vial per plant, or 2 vials per plant if you want to quantify 33P in both roots and leaves. The vials should be numbered from 1 to N before you start the experiment. They also should be placed in order in appropriate racks (PerkinElmer) adapted to the beta counter.
Tips
Young in vitro plantlets
MES hydrate (Sigma-Aldrich, catalog number: M8250 )
CaCl2 (Sigma-Aldrich)
KH2PO4 (Sigma-Aldrich)
33P-PO4 5 mCi/ml (40-158 Ci/mg, 1.48-5.84 TBq/mg, >99% isotopically pure, less than 0.5 μM Pi) (PerkinElmer)
Scintillation cocktail (PerkinElmer, Ultima GoldTM)
MgSO4
NH4NO3
KNO3
NaH2PO4
KI
FeCl2
MnSO4
ZnSO4
CuSO4
CoCl2
Na2MoO4
Thiamine
Pyridoxine
Nicotinic acid
Inositol
Sucrose
Agar
MS/10 medium (see Recipes)
Stock solution (see Recipes)
Incubation medium (see Recipes)
Desorption medium (see Recipes)
Equipment
Experiments should be performed on a bench or under a hood illuminated with white light (150 -180 μEm-2 s-1) during the incubation step
Ice-containing large boxes for the desorption step (all 12-well plates will be placed horizontally on ice for 2 h)
Tweezers for handling the plantlets
If necessary, a razor to separate roots and aerial parts
Micropipets
Shield for protection against radiations (plexiglass)
Scanner or camera (Epson America, model: Perfection V850Pro or Canon, model: Powershot SX130 ), respectively but other devices from other manufacturers could suit perfectly
Readers should cite both the Bio-protocol article and the original research article where this protocol was used:
Thibaud, M. and Marin, E. (2016). Measurement of 33P-PO4 Absorption Capacity and Root-to-leaf Transfer in Arabidopsis. Bio-protocol 6(5): e1741. DOI: 10.21769/BioProtoc.1741.