Abstract
Summary: The effects of the planting density of the seed potato crop, the date on which it was defoliated and the time at which it was lifted, on the weight, shape and number of eyes on progeny tubers in a given size grade, were small and were unlikely to be of practical importance.Size grade was both closely and linearly related to the number of eyes on a tuber and seemed to be a perfectly adequate practical method of grading seed tubers according to their number of eyes.