Inter‐morph pollen flow and reproductive success in a self‐compatible species with stigma‐height dimorphism: the influence of herkogamy and reciprocity.

Inter‐morph pollen transfer and its dependence on herkogamy and reciprocity are not completely understood in species with stigma‐height dimorphism. We asked whether total stigmatic pollen loads, inter‐morph fraction of pollen load and reproductive success differed between morphs in Jasminum malabaricum, a species exhibiting stigma‐height dimorphism. We tested whether higher herkogamy and reciprocity resulted in higher inter‐morph pollen deposition and reproductive success.We quantified individual‐level estimates of herkogamy, reciprocity, total stigmatic pollen load, inter‐morph stigmatic pollen fraction and fruit set for both morphs in naturally occurring populations of J. malabaricum.Total pollen load was higher in the long‐styled morph, inter‐morph pollen fraction was higher in the short‐styled morph, but fruit set did not differ between morphs. Higher herkogamy resulted in a higher inter‐morph fraction of pollen load and fruit set in the long‐styled morph of one population. In the other population, only reciprocity was found to be related to inter‐morph pollen deposition.This study is the first to quantify and report natural inter‐morph stigmatic pollen load in a species with stigma‐height dimorphism. Morph‐specific differences in pollen load were similar to patterns commonly observed in heterostylous species. The results highlight the importance of both herkogamy and reciprocity in facilitating inter‐morph pollen transfer. Population‐specific patterns indicate that local environmental factors determine the relative functional importance of herkogamy and reciprocity. [ABSTRACT FROM AUTHOR]