The big,empty and abortive pollen grains are abserred at the stage of uninuclear microspore.

单核期的小孢子出现壁发育不良和空花粉现象。

Pollen mother cells undergo meioses through simultaneous cytokinesis and give rise to tetrads of microspores, which are tetrahedrally arranged.

花粉母细胞行减数分裂，细胞分裂属同时型，产生小孢子四分，为四面。

Homogenous lines can be obtained in a very short time by haploidy breeding method such as microspore culture and anther culture.

要通过单倍育种途径可快速获得纯合材料，增加有益性状的选择几率，加快育种进程。