RAPD和ISSR标记对水稻化感种质资源遗传多态性的分析

运用RAPD和ISSR技术分析水稻化感种质资源的遗传多态性。从供试材料中筛选到具有多态性的RAPD引物12条，ISSR引物7条。RAPD引物共扩增到85条清晰的多态性条带，多态性条带比率为69．4％。ISSR引物共扩增到34条清晰的多态性条带，多态性条带比率为53．0％。对两种标记结果进行UPGMA聚类分析，结果极其类似，呈极显著的正相关(r=0．74)。聚类结果表明，地理位置相近的品种聚为一类。部分具有较强化感作用潜力的水稻品种亲缘关系很近，表明控制其化感作用性状的基因可能是等位的相同基因。而部分化感作用潜力差异显著的水稻品种聚为一类，这是由于人类在长期高产品种的定向选择过程中，水稻化感作用性状不被注意而丢失，遗传基础日益狭窄的原因。

Assesment of Genetic Diversity of Allelopathic Rice Germplasm Based on RAPD and ISSR

Random Amplified Polymorphic DNA (RAPD) and Inter-simple Sequence Repeat (ISSR) methods were used to detect the genetic diversity of 57 allelopathic rice accessions which were introduced from 10 countries or areas.A total of 12 RAPD primers and seven ISSR primers were indentified with polymorphism among the entries.For RAPD markers,85 polymorphic bands were produced,percentage of polymorphic bands (PPB) were 69.4%.For ISSR marker,34 polymorphic bands were generated,PPB were 53.0%.The result from the clustering analysis by UPGMA indicated that those accessions from the same geographical location were clustered into one group.It was also found that some rice accessions with higher allelopathic potential were clustered together,implying that the genes conferring allelopathy in those rice accessions might be isolocus.However,some rice accessions with different allelopathic potential clustered into the same group performed lower level of generic polymorphism which was attributed to oriented selection for other traits in breeding program.The estimates of correlation coefficient of RAPD and ISSR based on the genetic similarity matrices were significantly correlated.