botanyone
The monosulcate type is the most common pollen aperture pattern in monocots and basal angiosperms, and is considered as the ancestral condition for flowering plants. Toghranegar et al. describe microsporogenesis in 30 species belonging to eight monocot families, and find five different pathways associated with the production of monosulcate pollen grains. These pathways differ in the type of cytokinesis, the tetrad shape, and the presence and patterns of additional callose deposition after the formation of intersporal walls. In all the pathways, aperture location seems to be linked to the last points of callose deposition.
