Flowering and Reproduction Habits of Oryza rufipogon in Wanning City of Hainan Province

Oryza rufipogon population in Wanning city is the largest one in Hainan Province.In order to determine the possibility of gene flow from cultivated rice to wild rice,the flowering date,daily opening time,seed setting rate and pollen fertility of the Oryza rufipogon were investiged.The results indicated that the eastern and western sub-populations had obviously differences on many habits.The flowering of the eastern sub-population was 15 days earlier than the western sub-population.The average seed setting rate was 8.7% in the eastern sub-population,while that in the western sub-population was 62.1%.Statistics analysis showed that they had significant difference at 1% level.Nevertheless,the daily opening time and pollen fertility between the two sub-populations almost had no significant difference.The flowering date and opening time in the eastern sub-population met with the close-by regenerating Oryza sativa.Although the existing conditions fit to gene flow,it could not be concluded that gene flow happened between the Oryza rufipogon population and the close-by regenerating Oryza sativa in nature.However,for the requirement of wild rice conservation,it′s necessary to design isolation distance between Oryza rufipogon population and transgenic rice varieties released in this area.