SCREENING ARABIDOPSIS FOR MUTANTS IN MINERAL-NUTRITION

Arabidopsis thaliana is a small herbaceous plant which is used as a mo del plant for defining the molecular basis of many plant processes. Th e advantages of this plant for genetic studies are its small, well-cha racterized genome, a short life cycle, large seed set and small seed s ize. The analysis of mutants of this plant has proved useful in unders tanding basic plant processes. To isolate Arabidopsis mutants in miner al nutrition, we have devised a method of screening based on X-ray flu orescence spectrometry (XRFS) analysis of leaves. We have identified t hree mutants in P and Mn nutrition after screening over 100 000 seedli ngs. These mutants show either excessive accumulation of P or Mn in sh oots or an inabilty to accumulate normal concentrations of P.