1. The tissue in a plant anther or ovule from which spores or gametes develop; the sporogenous tissue.
Usage: botany; technical

Examples

• The archesporium in the anther gives rise to pollen grains.
• During flower development, the archesporium differentiates into microspore mother cells.
• In the ovule, the archesporium produces the megaspore mother cell.
• Botanists study the archesporium to understand gametogenesis in plants.
• The archesporium is surrounded by layers of sterile tissue in the anther.