Effect of warm water treatment on seed germination characteristics of Astragalus membranaceus var.mongholicus L

The seeds of Astragalus membranaceus var.mongholicus were treated at constant and variable temperatures for different durations.The seed germination rate,germination potential,and germination index were determined,and the optimal warm water method to break seed dormancy was explored.Results showed that (1) seed dormancy was counteracted by soaking seeds with warm water,with variable temperatures better than constant temperatures.(2) The order of treatment was 60℃> 70℃> 80℃,and the germination rates were 2.87 and 2.31 times that of the control at 60℃ for 2 min and 5 min,respectively (P < 0.01).(3) Treatment duration and soaking temperatures significantly affected seed germination.Compared with the control,the germination rate increased with soaking time at first,but decreased afterwards.There was a significant positive correlation between germination index and soaking temperature (P< 0.01),with a correlation coefficient of-0.226,as well as between soaking temperature and germination potential and germination index,indicating that soaking seeds in warm water improved germination without damaging seed viability.