OBJECTIVETo reveal the flowering characteristics of Panax stipuleanatus and provide theoretical basis for distant hybridization between P. stipuleanatus and P. notoginseng.

METHODDuring the blossom of P. stipuleanatus, we observed and investigated blooming phenophase, growth dynamics of inflorescence, pollination and seed setting of its population and the flowering process and its period, the regularity of flowering and pollinating of the floret. Statistic analyses were carried out.

RESULT AND CONCLUSIONThe population florescence of P. stipuleanatus was about 60 d. The average florets quality of umbel was 44-47. The average natural pollination rates were 73.32%-95.39%. The average seed setting rates was 35.65%-51.76%. The highest growth periods of inflorescence are from March 25 to April 4. The diameter, the height and the length of its inflorescence in 10 d increased 44.65%, 42.19% and 106.25%, respectively. The whole stereotype period was the May beginning. The time that the floret from petal opening to withering it generally needed 36-48 h, 60 percent of the floret finished auther pollinating during the same day and 40 percent until the next day. The flowering and pollinating peak periods were 14:00-15:00, the flowering numbers was 28.48% of the total flowering amount and the pollinating numbers were 38.63% of the total pollinating amount. The high temperature (20-30 degrees C) and the low humidity (RH < 60%) were beneficial to flowering and pollinating.