Abstract: From March to May 2008, an investigation was conducted on the flowering phenology of five natural Eomecon chionantha Hance populations in  Ciping, Huang’ao, Jingzhushan, Liping and Shuikou at Mt. Jinggang of Jiangxi Province, and the indices such as flowering amplitude, relative flowering intensity, and flowering synchrony were adopted to study the effects of the flowering phenology on the reproductive features of the populations. The flowering period of test populations was from late March to early May, lasting 24-46 days, and Jingzhushan population had a significantly longer flowering period than Ciping population. The flowering duration of individual plants was averagely 11-21 days, but the life span of single flower was usually 3-5 days. The flowering had a single peak, i.e., concentrated in a certain period. Same as the majority of subtropical plants, E. chionantha had a lower relative flowering intensity, being from 10% to 30%. The correlation analysis of flowering indices and reproductive features showed that the onset time of flowering had significant negative correlation with the duration of flowering but significant positive correlations with flower number and fruit set ratio, the duration of flowering also had significant positive correlations with flower number and fruit set ratio, the fruit set ratio was significantly positively correlated flower number, and the flowering synchrony index was negatively correlated with the onset time and duration of flowering and the flower number. The populations with earlier onset flowering date showed a longer duration of flowering than the populations with later onset flowering date, and the populations with more flowers showed a longer flowering duration than those with lesser flowers. There was a higher fruit set ratio for the populations with earlier onset flowering date and longer flowering duration, as compared to the populations with later onset flowering date and shorter flowering duration, and the populations with higher flowering synchrony index showed a later onset flowering date, shorter flowering duration, and fewer flowers. As an endemic plant in China, E. chionantha exhibited a so-called “mass-flowering” pattern, which could be regarded as an adaptation strategy to the environment to ensure its reproductive success.

Key words: Sinorhizobium fredii HN01DL, Glycine max rhizosphere, Root colonization, Nodulation, luxAB