Pollination Biology, Self‐incompatibility, and Sterility in Ipomoea Pandurata (L.) G. F. W. Meyer (Convolvulaceae)

Ipomoea pandurata rarely produces seed. Sporophytic self‐incompatibility is a secondary factor contributing to the reduced seed production because the principal pollinators, Bombus pennsylvanicus (Apidae) and Melitoma taurea (Anthophoridae), effect cross‐pollination in most populations. Sterility, expressed as pollen tube failure in the style and as a sterility mechanism in the ovary, is the primary factor accounting for reduced seed production. It is difficult to reconcile the extensive geographical distribution of I. pandurata with this sterility.