Size and Shape of Plots for Estimating Yield Losses from Cereal Foliage Diseases

Abstract

SUMMARY Data from uniformity trials on healthy and diseased wheat and oat crops showed that the coefficient of variation for yield decreased as plot size increased and became nearer to square in shape. Infection with Septoria leaf blotch of oats and powdery mildew of wheat did not appear to affect yield variability. Plots larger than rod row size (where 16 ft of the centre row of 3 rows is harvested) are recommended to detect differences of 10 per cent in yield between two treatments.