Abstract: Gametic incompatibility and low hybrid seed vigor are two of multiple species reproductive barriers. In order to infer the gametic incompatibility and hybrid seeds fitness of sympatric populations among Hedychium forrestii, Hspicatum and two morphs of Hyunnanense, we have done a set of field cross experiments among these Hedychium species in Lancang, Yunnan Province, and then compared the fruit set, seed number per fruit and germination data of seeds from cross experiments. The experiments showed that the gametic compatibility between these species are different, and the germination performances of hybrid seeds are worse than the intraspecies outcrossed seeds. These results suggested that gametic incompatibility is not the effective reproductive barrier among these species and hybrid seeds fitness is the incomplete reproductive barrier among these Hedychium species, which indicated that hybridization may exist among them.

Key words: Hedychium