Anther Dehiscence and Pollen Transfer
Anther dehiscence simply means the release of pollen grains from dry and mature anthers. It involves the rupturing of anther wall due to the mechanical pressure developed by the fibrous thickenings of endothecial cells along the stomium (the area where mechanical layer does not differentiate). If endothecium is lacking, the mechanical role is passed on to epidermal cells. In most of the angiosperms the stomium is a narrow strip along the entire length of the anther lobe. It may, however, also be restricted to a lid or valve (Berberidaceae) or pores (Solanum, Cassia, Polygala).
The transfer of pollen can be autogamous (self-pollination) in which the pollen grains of an anther reach the stigma of the same flower. In cross-pollination, - the pollen of one plant reach the pistil of some other plant of the same species. If the pollination occurs between two flowers of the same plant it is termed geitonogamy and, if it is between two flowers on different plants it is xenogamy.