Fig. 1. Evolution of seed weight and seed oil concentration (oil concentration) of intermediate achenes, of hybrids DK3900 (A) and Paraiso 20 (B) cultivated at two plant population densities. Lines indicate the models fitted to the data. For DK3900: Seed weight = 9.8 + 0.067 thermal time (r² = 0.97, n = 8, P < 0.001), for thermal time < 657°Cd; Seed weight = 53.6 mg, for thermal time 657°Cd (at 3 plants m^–2); Seed weight = 6 + 0.042 thermal time (r² = 0.76, n = 20, P < 0.001), for thermal time < 796°Cd; Seed weight = 39.8 mg, for thermal time 796°Cd (at 6 plants m^–2); Oil concentration = –40 + 1.017 thermal time (r² = 0.96, n = 18, P < 0.001), for thermal time < 569°Cd; Oil concentration = 539 mg g^–1, for thermal time 569°Cd (at 3, 6 plants m^–2). For Paraiso 20: Seed weight = 9.8 + 0.068 thermal time (r² = 0.98, n = 8, P < 0.001), for thermal time < 737°Cd; Seed weight = 60.1 mg, for thermal time 737°Cd (at 3 plants m^–2); Seed weight = 1.2 + 0.054 thermal time (r² = 0.93, n = 20, P < 0.001), for thermal time < 755°Cd; Seed weight = 41.9 mg, for thermal time 755°Cd (at 6 plants m^–2); Oil concentration = 8 + 1.03 thermal time (r² = 0.95, n = 17, P < 0.001), for thermal time < 524°Cd; Oil concentration = 548 mg g^–1, for thermal time 524°Cd (at 3, 6 plants m^–2).