(A) Nodulated root dry matter, (B) root dry matter, (C) tap root length and (D) total root length of five pea genotypes, from the four-leaf stage until physiological maturity or the beginning of seed filling. 4L, 10L, BF, BSF and PM indicate the developmental stage and correspond to four-leaf stage, ten-leaf stage, beginning of flowering, beginning of seed filling and physiological maturity, respectively. Each point is the mean value of three replicates. Vertical bars represent LSD (P < 0·05).