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Primula Hance(Gesneriaceae)is a group that has attracted much attention in recent years. Its intricate species diversity and its endemic distribution among species have aroused great interest among taxonomists and botany researchers. Except for a few species, like Primulina eburnea (Hance)Y. Z. Wang, most species have a very narrow distribution range, which belong to narrow distribution species or endemic species. In order to reveal the effects of the pollination biology and breeding system of P. eburnea on its reproductive process and colonization ability, we systematically studied the flowering phenology, the pollen and stigma viability, the species and visiting behavior of flower visiting insects, the pollen ovule ratio, the OCI index and the seed setting rate of manipulated pollination of P. eburnea. Besides, we explored whether its reproductive processes such as pollination had a positive effect on the spread of P. eburnea. The results showed that the natural flowering stage of P. eburnea was from March to May, and the entire flowering stage was about 45 d. Its full flowering stage was about 20 d, and the single flower flowering stage was 6-8 d. Pollens had the strongest viability 1-2 d after flowering, stigma did not have receptivity before flowering. The pollen ovule ratio was 537, and the hybridization index was 5. Bagged and emasculation could not bear fruit, indicating that this species did not have apomixis. Compared with natural pollination, the seed setting rate of hand self-pollination was slightly lower, and the seed setting rate of hand xenogamy was slightly higher, indicating self-compatibility. The main pollinators of P. eburnea were Anthophora florea and Bombus sp. Therefore, higher nectar volume, larger pollen amount and stronger pollen viability of P. eburnea were obviously beneficial for it to complete the entire process of pollination and reproduction. This result was obviously conducive to the colonization of P. eburnea and then widely spread in the karst areas of South China to Southwest China. [ABSTRACT FROM AUTHOR]