Abstract: The main pollinator behaviors of Coreopsis lanceolata were observed. The average flight distance of native bees is 12.71 cm, and the farthest distance is 60 cm in population. They usually stay on one florescence for 10 sec. It could visit 2.59 plants between its come-and-go in population. Our results showed that high pollen viability and pollinator movement and a lot of visiting bees ensure high out-crossing rate (the yield of seeds is about 12000 per plant). In this paper, we simulated the distribution of different genetic ramets of C.lanceolata, the results showed that different genetic ramets mixing standard influence the seed-setting remarkably. High genetic diversity of population, the pollinator movement and the guerrilla growth strategy could disperse the ramets, these traits lower the rate of geitonogamy. Therefore, the disadvantage of clonal outbreeding mating system could be avoided effectively, C.lanceolata could keep a high outcrossing rate. This strategy could improve its invasive ability.

Key words: Coreopsis lanceolata, clonal breeding, mating system