We have examined the effect of the protein phosphatase inhibitors okadaic acid and microcystin on pollen-pistil interactions in Brassica. Inhibitor-treated flowers or floral buds were pollinated with untreated pollen and examined for pollen tube growth by fluorescence microscopy. Our results show
When components of the mature pollen grain of Brassica oleracea are applied to the cuticularised surfaces of the stigmatic papilla, a number of changes can take place in the architecture of the subjacent cell wall. Treatment of the papillar surface with isolated pollen coating evokes a rapid and