Affiliation: | (1) Division of Plant Industry, CSIRO, G.P.O. Box 1600, 2601 Canberra, ACT, Australia;(2) Present address: GBF, Mascheroder Weg 1, D-3300 Braunschweig, FRG;(3) Present address: John Innes Institute, Colney Lane, NR4 7UH Norwich, England;(4) AFRC Institute of Plant Science Research, Colney Lane, NR4 7UH Norwich, England |