callose

The tetrasporophyte wrapped by callose is of simultaneous type.

四分体呈四面体型，被胼胝质壁所包围。

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

营养细胞的细胞质中继续积累胼胝质，花粉熟对胼胝质在小孢子形和发育程中的功能进行了讨论。