Fig. 5. Simulated grain yield response to the increased specific leaf area (SLA) trait over normal genotypes for 30 () and 90 () kg N ha^-1 on clay soil at (a) Wongan Hills and (b) Merredin, Western Australia and measured yield response to early-vigor lines (BC₂F₂–derived lines of cultivar Amery crossed with a high-vigor donor line) for 1997–1999 with low (•) and high () N input and the high-vigor cultivar Westonia with high N input () (Botwright et al., 2002). Zero change grain yield line is also shown (_...).