The tetrasporophyte wrapped by callose is of simultaneous type.

四分体呈四面体型，被胼壁所包围。

These results indicate that callose metabolism is active and very important not only in microsporogenesis but also in microgametogenesis in rice.

胞的胞中继续积胼，花粉成熟对胼小孢子形成和发育过程中的功能进行了讨论。

Abbreviation: T: Tapetal; N: Nucleus; TE：Tetrad; TW: Wall of tapetal cell; V: V acuole; D: Dictyosome; C: Callose; M: Mitochondria.

绒毡层胞，N：胞核，TE:四分体，TW：绒毡层胞壁，V：液胞,D：高尔基体，C：胼壁，M：线粒体。