Fig. 2.

Sulphate deficiency suppresses lateral root development. DR5::GUS seedlings treated identically in Fig. 1 were used to measure the primary root (PR) length and count under microscope the number of the emerged or elongated lateral roots (LR) and the lateral root primordia (LRP). Various stages of LRP were determined according to Malamy and Benfey (1997). The average of 4–7 seedlings measured or counted were shown with the bar representing the standard deviations. (A) Primary root length. (B) Total number of lateral roots and LRP for each seedling. (C) Density of lateral roots or LRP on the primary roots. Density is expressed as the average number of LR or LRP on per cm primary root (PR). Different letters (in B and C, uppercase letters for the LR, and lowercase letters for the LRP) above the columns indicate statistically significant difference (P=0.05)