Phosphorylation in crested wheatgrass seeds at low water potentials

Crested wheatgrass seeds [Agropyron desertorum (Fisch. ex Link) Schult.] were tested for their ability to carry on phosphorylation reactions at low water potentials. Seeds were treated with ³²P labeled sodium phosphate and incubated in air having different controlled relative humidities. Ion exchange chromatography and radioassay of phosphate esters indicated that some phosphorylation occurred at a water potential of −880 atmospheres. Seeds did not incorporate ³²P in nicotinamide adenine dinucleotide, adenosine triphosphate, and uridine diphosphate hexose until they were moistened to a water potential of −130 atmospheres.