Figure 1. Effects of mildew infection and fungicide spraying on yields of GM wheat lines.

Example of significant transgene × environment (presence/absence of powdery mildew) interaction in GM spring wheat in a glasshouse experiment. GM plants (circles  =  Pm3b#1 to #4) have higher yield than control plants (squares  =  S3b#1–4) in the presence but lower yield in the absence of mildew (fungicide spraying); light grey lines were drawn to make interactions between transgene and environments visible; error bars represent ±1 standard error (back-transformed from square root scale).