Correlation between speed of pollen tube growth and seedling height in Zea mays L.

Abstract

EVIDENCE of a correlation between gametophytic and sporophytic qualities could be useful because gametophytic competition is both frequent and severe in natural populations¹. A statistically significant correlation has been found in Zea mays between the relative speeds with which pollen tubes penetrate the lengths of styles and the relative competitive abilities of the resultant zygotes². This correlation was found in a study of mixtures of two pollen types when the sporophytic competition was limited to interactions between zygotes developing within a common inflorescence. It is therefore possible that faster growing pollen tubes allow a relatively early start in postfertilisation growth which accounts for the competitive superiority of the resultant zygotes, although there is a conflicting report³.