Fig. 13. Seasonal trend in the (a, b) total root biomass (B_R) in a 1-m soil profile and (c, d) shoot biomass (B_S), and (e, f) the root to shoot ratio (B_R/B_S) for spring wheat during the (a, c, e) 1993 and (b, d, f) 1994 growing seasons. Sampling occurred on day after emergence (DAE) 16 and DAE 3 at the 3-leaf, DAE 36 and DAE 26 at tillering, DAE 63 and DAE 40 at stem-elongation, DAE 92 and DAE 102 at anthesis, DAE 113 and 118 at soft dough, and DAE 159 and DAE 154 at hard dough developmental stages during the 1993 and 1994 growing seasons, respectively. Each mean datum for B_R was derived from four replications during vegetative development (i.e., 3-leaf, tillering, stem-elongation) and two replications during reproductive development (i.e., anthesis, soft dough, hard dough) (i.e., means and SE of replication means based on n = 4 and n = 2, respectively). During 1994, the B_R was collected for four replications during vegetative and three replications during reproductive development (i.e., means and SE of replication means based on n = 4 and n = 3, respectively). The total B_S (i.e., aboveground green and brown leaves, sheaths, culms and ears, and belowground crown tissue) was collected for four replications both seasons (i.e., means based on n = 4, SE of replication means based on n = 4). Symbols in legend, source of variance, and results from ANOVA same as described in Fig. 1.