The mildew infection equals the proportion of pots with strong powdery mildew infection up to flag leaves. Phenological stage, plant height, vegetative mass, seed number and seed yield were measured to assess the plant performance. A: mean of four lines at different soil nutrient levels (circles = additional fertilizer, squares = no fertilizer); transgene × fertilizer environment interactions were never significant; light grey lines were drawn to make this visible; error bars represent ±1 standard error (back-transformed, see methods). B: proportional difference between GM and control plants for each of the four offspring lines but averaged across nutrient levels (white bars = offspring pair 1 (Pm3b#1 vs. S3b#1), light grey = offspring pair 2, dark gray = offspring pair 3, black bars = offspring pair 4); x-axis log-scale with original values (100 * GM/control); bars extending to the right from the vertical zero line indicate higher values in GM than in control plants; significant GM/control x offspring pair interactions indicated by asterisks (* P<0.05; ** P<0.01; ***P<0.001).