Floral Manipulations Reveal the Cause of Male Fitness Variation in Experimental Populations of Eichhornia paniculata (Pontederiaceae)

Abstract

In populations of self-compatible, tristylous Eichhornia paniculata plants of the long-styled morph (L) consistently sire fewer seeds on the mid-styled morph (M) than do plants of the short-styled morph (S). This mating asymmetry results in gender differences between the L and S morphs. Differences in floral architecture may predispose morphs of heterostylous plants to differential success as male parents. Architectural constraints on male performance imposed by the placement of female and male organs within flowers may be of general importance for floral evolution. -from Authors