The tetrasporophyte wrapped by callose is of simultaneous type.

四分体呈四面体型，被胼胝质所围。

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

营养细胞的细胞质中继续积胼胝质，花粉成熟对胼胝质在小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.

绒毡层细胞，N：细胞核，TE:四分体，TW：绒毡层细胞，V：液胞,D：高尔基体，C：胼胝质，M：线粒体。