Abstract:Male sterile individuals were discovered in the population of Erigeron breviscapus planted in Luxi Yunnan,and the frequency was about 1.06×10-4.The morphology and the anther development of the newly male sterile individuals was examined and the pollen vigor and seed-setting percentage of the individuals were tested.It was shown that the modality of root,peduncle and leaf was similar between sterile and normal fertile plants,but sizes of tubular flowers and anthers and filament lengths were litter and no pollen grain or pollen without vigor in the male sterile plants.At the microsporocyte phase,tetrad phase,microspore phase and early uninuclear phase in the anther development,the microsporocyte and tetrad break down and form anther without pollen grain,or the microspore and uninuclear pollen break down and form sterile pollen grain with different forms and extine sculptures,which resulted from the premature degeneration of the tapetum.