Fig. 2. Relationship between maize grain yield and indicators of available water at flowering (W), expressed as (A) water use from 20 d before to 20 d after flowering (W1), (B) available water in the soil at 20 d before flowering plus rainfall from 20 d before to 20 d after flowering (W2), (C) rainfall from 20 d before to 20 d after flowering (W3), and (D) rainfall from 30 d before to 20 d after flowering (W4). Parameters of the fitted curves are (A) a = 9065 ± 151, W₀ = 52.8 ± 5, and b = 26.6 ± 4.6; (B) a = 9098 ± 103, W₀ = 90 ± 5.5, and b = 46.2 ± 5.7; (C) a = 9229 ± 215, W₀ = 37.3 ± 5, and b = 30.7 ± 5.7; and (D) a = 9260 ± 178, W₀ = 44 ± 6.2, and b = 45 ± 7.2.