Fig. 6.

Root morphology and the percentage of the root hair zones in bean hairy roots at two P levels. (A) Photographs of roots in bean hairy roots at two P levels. (B) Percentage of the root hair zone in bean hairy roots at two P levels. Bean hairy roots were grown in media containing 0 μM (–P) or 1.25mM (+P) KH₂PO₄ for 14 d. Ten lateral roots were selected from each replicate for further analysis. Photographs were taken of three zones of the lateral roots, namely the root tip, root middle, and root base. Scale bars=1mm. OX1 and OX2 indicate two transgenic bean hairy root lines overexpressing PvSPX1, PvSPX2, or PvSPX3. CK1 and CK2 indicate the two transgenic lines transformed with the empty vector. Asterisks represent significant differences between two P treatments for the same trait at the 0.05 level.