Abstract: In the study，the pollen viability of the cultivars‘Maobaiyu’and‘Fenfurong’was determined via culture in vitro，and the pollen germination and pollen tube growth were observed. The results showed that the pollen germination rate and growth of pollen tubes were promoted significantly by Ca²⁺ but not influenced by H₃BO₃；The viability of pollen collected from middle parts of inflorescences was signi?cantly higher than that from external or inside of inflorescence. Shading decreased pollen viability. Pollen viability decreased with increasing storage time under different temperatures. The appropriate storage time of pollen was 8 days and 6 days at room temperature，25 days and 20 days at 4 ℃，21 days and 18 days at–80 ℃ respectively for‘Maobaiyu’and‘Fenfurong’，and 25 days at–20 ℃ for both cultivars. Desiccation duration for 2 hours could increase the viability of pollen stored at–80 ℃，producing better results than that of 4 hours and 6 hours treatments. The pre-freezing treatment reduced pollen germination. The methods of defrosting frozen pollens at 35 ℃ for two minutes or in trash ice were better than other defrosting treatments.

Key words: groundcover chrysanthemum, pollen, pollen viability, storage characteristic