Megaspores are produced from the megaspore mother cells after

The process of formation of megaspores from the megaspore mother cell is called megasporogenesis. Ovules generally differentiate a single megaspore mother cell (MMC) in the micropylar region of the nucellus. It is a large cell containing dense cytoplasm and a prominent nucleus. The MMC (2n) undergoes meiotic division. Meiosis results in the production of four  haploid megaspores.