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Despite of the harsh environmental conditions, alpine regions have very specialized and diverse plants. Abiotic factors play important roles in the formation and evolution of floral traits of these alpine plants. In this paper, the hairy corona of alpine plant Comastoma pulmonarium was studied to explore the evolutionary and adaptive significance of this distinctive floral structure in the extreme alpine environment and its effects on plant reproductive fitness. The results showed that in artificially corona removed flowers, pollen grains in anthers (t = 2.61, P<0.05) and fertilization rate (t=2.05, P<0.05) decreased greatly after rain-wash. However, there were no significant differences of the seed weight and seed germination rate between artificially corona removed flowers and control flowers. Additionally, pollen germination rate reduced significantly due to water immersion (t = 30.67, P<0.001) and direct exposure to sunligh t(t = 9.89,P<0.001), indicating that hairy corona could maintain viability of pollen grains in front of rain immersion and intense solar radiation. This study indicates that the hairy corona of C. pulmonarium has adaptive significance for both male and female reproductive success in the harsh environment of alpine regions, and further confirms selection on the flower morphology of alpine plants by abiotic factors. [ABSTRACT FROM AUTHOR]