A mutagenesis rice mutant L2 layer aberrant differentiation lad1 have the differentiation of L2 layers of male and female reproductive organs. Genetic analysis indicated lad1 was a single recessive gene. By microscopic observation, we discovered the lad1 mutant had one or two regular layers in the anther wall and at least seven archespores or archespore-like cells in the ovules in stage Ov2. Because of seed setting by being pollinated with the pollen of wild type, at least one MMC can undergo meiosis and produce functional megaspores. By compared with nzz/spl mutants in Arabidopsis and mps1 mutant in rice and microscopic observation, we purpose that LAD1 gene should be an allele or upstream gene of MSP1 and regulate the development and differentiation of L2 layers in anthers and ovules by cell communication between cell layers.