Abstract: Malus sieversii is a tertiary relict plant. As a precious fruit germplasm, it has some excellent traits, such as stronger anti-cold ability, the resistance to insect, disease and drought. In this paper, the biological characteristics of seed germination in different populations of Malus sieversii were explored. The results show that 1 000-seed weight varied among different populations, and those of HR were the heaviest (26.86 g), subsequently with GY population (25.63 g), XY population (23.58 g) and NY population (19.76 g). By comparing three different methods of seed germination, it is concluded that the germination rate was much higher with removing the seed coat, reaching to 100% after 3 days. However, the seeds stratified outdoor at low temperature started to germinate after 40 days, with germination rate of 85.67%. When treated in freezer at 4 ℃, the seeds germinated after 60 days, with germination rate of 91.33%. The seed coat could be the main limiting factor for its germination. According to the study, it is can also be concluded that seeds stored for less than 3 years have higher germination rate of over 87%, seeds stored for 7 years dropped prominently to 31.6%. These results also show that germination rate in HR population was the highest (93%), followed by XY population, and that in NY population was the lowest (74%).

Key words: Malus sieversii, endangered plant, seed, germination