Heterostyly

Heterostyly is a term from the floral biology. This refers to the occurrence of different types of flowers within a plant species. The flowers differ from each length of the stylus and the stamen positions. Thus, there are in many representatives of the genus Primula each about the same number of individuals with short style and high stamen position, or with long stylus and lower stamen position. Such dimorphic heterostyly or Distylie example also comes with some representatives of the buckwheat family ( Polygonaceae ), wood sorrel family ( Oxalidaceae ) or Madder Family ( Rubiaceae ) ago. There are also trimorphic Heterostylie or Tristylie. Here's the androecium in two, split, different, Stamen circles in the position. This results in three different Blütenmorphen: scar at the top, middle or bottom position and the stamens on each of the other two positions. Examples of Tristylie can be found in the purple loosestrife ( Lythrum salicaria ), and most members of the genus Oxalis.

Even Charles Darwin was able to show that only at a cross-pollination of both types, an optimal fruit set takes place, so Heterostylie will aim to promote cross-pollination.

Meanwhile, it was found that in the so-called heterostyly not only the stylus length and stamen position are crucial. Rather, different large pollen and pollination Narbenpapillen influence this process. For this reason, there is a tendency to replace the term Heterostylie by the term Heteromorphie.