DIFFERENT HELPER CELL GROUPS. “Depending on their sex and their stage of development, plant reproductive cell lineages are associated with different supporting cell populations. In the stamen, male meiotic cells are invested by a layer of sporophytic (somatic) tapetal cells, which are essential for postmeiotic development and, particularly, the synthesis of the sporopollenin pollen wall and its coating.”
http://www.sciencedirect.com/science/article/pii/S1534580713000427