Root development has become a mature field of research in Arabidopsis. Elegant cell-faith and laser ablation studies (by Scheres, Utrecht) and well described mutants some of them affected in specific cell layers of the roots (Di Laurenzio and Benfey, New York), have been important tools in the understanding of this important plant structure.
The development of leaf primordia was studied by Pickett (Eugene) with temperature sensitive mutants. C. Bellinni reported on new seedling mutants studied at the INRA in Versailles. Some of these mutants seem to be affected in the cytokinin response.