Developmental differences between hermaphrodite and female-like flowers in a non-model horticultural plant <i>Dianthus hybrida</i>

The popular ornamental flowering plant Dianthus hybrida cv. Telstar Scarlet has been found to exhibit two populations, each with distinct flower morphology: female-like and hermaphroditic. In this work, flower development of D. hybrida was characterized through scanning electron microscopy, light- or stereo- microscopy, from flower meristem formation to the fully matured, open flower. The difference between hermaphrodite and female-like plants was initially marked by the phenomenon of anther shrinking in the latter, which was closely associated with pollen shrinking phenomenon, and soon followed by differential elongation rates of pistils and stamens. Furthermore, the female-like anther, albeit exhibiting delay in pollen development initially, could produce microspores, resembling its hermaphrodite counterparts at some point, before shrinking. However, female-like’s pollen and cell wall size never became as large as the hermaphrodite’s.