Biological characteristic response of different alfalfa varieties to mutation induced by space flight

Space breeding is a new way of agricultural breeding with high variation,highyield, goodquality, early maturity and strong stress resistance. Effects of satellite carrying three Medicago sativa varieties were studied. The results showed that the plant height of Zhongmu No.1 at seedling stage was significantly lower than the ground control, but the height increased at branching and initial flowering stages; The height of Longmu 803 at seedling and branching stages had a significant increase, and that of initial flowering stages was not significantly different; The height of Aohan at three plants stages were significantly higher than that of control. In conclusion, different mutagenic effects of space flight differed with plant varieties and growth stages, this may be caused by different sensitivity to mutation from different alfalfa varieties