中文摘要：

目的探讨太空环境对甘草的诱变作用。方法利用返回式卫星搭载甘草,18d后返回地球（飞行回收舱平均辐射剂量为0.102mGy·d^-1,飞行远地点距地球350km,重力为10-6N）,搭载种子返回地面后与对照组同时播于实验田中,取生长3年的甘草叶子用作ISSR分析,应用简单序列重复（ISSR）分子标记技术分析甘草基因组的变异情况。结果最终10条能产生清晰重复多态性条带的ISSR引物用于检测鄂托克前旗样品的基因组多态性,9条能产生清晰重复的多态性条带的ISSR引物用于检测杭锦旗样品的基因组多态性。太空飞行组与地面对照组的相似系数分别为0.8868和0.8723,遗传距离分别为0.1201和0.1366,基因组的多态性频率为20.3%和20.7%,多态性片段大小在200～1900bp之间。结论太空环境对甘草基因组产生了一定的诱变作用,这些变化表明空间育种是一种新型有效的育种方法并且对保护濒危甘草资源做出贡献。

英文摘要：

OBJECTIVE To investigate the effect of space environment on medicinal plants, the plants of Glycyrrhiza uralensis Fisch. METHODS Licorice （Glycyrrhiza uralensis Fisch） seeds were carried on a recoverable satellite for 18 d （the average radiation dose in the flight recovery module was 0.102 mGy·d^-1, the distance from flight apogee to earth was 350 km, gravity 10^-6 N） . After returning to Earth, the seeds were germinated and grown to maturity. The parallel ground-based seeds were also planted under the same conditions. The leaves of licorice were used for inter-simple sequence repeat （ISSR）. RESULTS Ten primers were selected to examin the amplification of the ordos group, 9 primers were selected to measure the amplification of the hangjinqi group. The similarity of the two groups were 0.886 8 and 0.872 3. The genetic distance were 0.120 1 and 0.136 6. The degree of gene polymorphism were 20.3% and 20.7%.The polymorphic bands ranged approximately from 200 to 1 900 bp. CONCLUSION These results indicate that space rays induce DNA variation to some extents in Glycyrrhiza uralensis. These changes indicated that space flight may be a new effective method for the breeding and cultivation of licorice so as to preserve this endangered medicinal plant.