LATERAL ROOT PRIMORDIUM INCEPTION IN ZEA-MAYS L

Counts of the frequency and estimates of cell number of primordia present in successive segments of the primary roots of Zea mays L. have been used to investigate the initiation and distribution of primordia along the root axis. Primordium inception was not confined to a restricted, sub-apical part of the primary, but took place over the distal 5-8 cm or more. Few seemed to be initiated once lateral emergence began. Most primordia completed their development and emerged as laterals within a fixed period of time, irrespective of their point of origin along the primary. Primordium initiation and lateral emergence were not strictly acropetal in these roots. © 1990.