Development of Pollen in Cyperaceae
In all members of the Cyperaceae out of the four nuclei formed after meiosis, only one functions, the others degenerate. The functional nucleus remains in the centre and the three non-functional nuclei are pushed to a side. In Cyphers, Kyllinga, and Scirpus the non-functional nuclei are separated from the functional nucleus by a wall. Walls are also laid between the nonfunctional nuclei. The functional nucleus divides to form a vegetative cell and a generative cell.
The non-functional nuclei may also begin to divide but the divisions are abortive, and they eventually degenerate. Thus in a tetrad, only one pollen grain is functional. This feature is similar to the behavior of megaspores in the development of monosporic embryo sac.