Table II. Summary of the architectural data of 15-d-old maize plants grown in aeroponics

Values shown are means ± se. Crown roots were about 2 cm long at the end of the experiment and were not analyzed. LAUZ, Length of apical unbranched zone; LR, lateral root. Roots are named according to Hochholdinger et al. (2004). The growth rate of lateral roots is estimated in their linear growth phase. The validity of the insertion angle is questionable, since images are two-dimensional projections of three-dimensional root systems.

Root DataValue
Primary
 Growth rate (mm d−1)37.0 ± 0.2
 Diameter (mm)1.4 ± 0.3
 Branching density (LR cm−1)5.9 ± 2.3
 LAUZ (mm)146.8 ± 54.8
Seminals
 Growth rate (mm d−1)31.0 ± 0.6
 Diameter (mm)0.9 ± 0.4
Laterals
 Growth rate (mm d−1)0.6 ± 0.17
 Diameter (mm)0.48 ± 0.16
 Insertion angle (°)65.6 ± 14.3