盐渍条件下野大豆群体的遗传分化和生理适应:同工酶和随机扩增多态DNA研究

黄河三角洲野大豆(Glycine soja Sieb. et Zucc.)盐渍群体的耐盐性高于附近的正常群体。群体内个体间耐盐能力差别很大。盐渍群体有比最耐盐的栽培大豆(G.max (L.)Merr.)品种耐盐能力高得多的个体,也有对盐相当敏感的植株。同工酶分析表明群体内高水半多态性,但酶谱与抗性没有相关性。盐渍与正常群体间的遗传一致性高达0.96。用改良的随机扩增多态DNA(RAPD)方法,10个引物扩增得出群体内多态位点百分数为68/188=0.36。看来,绝大多数位点与耐盐能力无关。上述资料说明,盐渍条件下野大豆自然群体的高度遗传多样性和发育变通性,可能足对盐胁迫强度随时随地变化的环境的适应。

GENETIC DIFFERENTIATION AND PHYSIOLOGICAL ADAPTATION OF WILD SOYBEAN (GLYC1NE SOJA) POPULATIONS UNDER SALINE CONDITIONS: ISOZYMATIC AND RANDOM AMPLIFIED POLYMORPHIC DNA STUDY

A higher level of salt tolerance in saline populations of wild soybean ( Glycine soja Sieb. et Zucc.) has been found in the Yellow River Delta. The levels of salt tolerance for individuals within populations vary widely. In the saline populations, there are a few plants with much higher tolerant level than that of the most tolerant cultivars. such as Morgan, and others as saline sensitive plants. Isozyme analysis showed a high level of genetic diversity, however, no relationship was found between isozymatic patterns and salt tolerance. Saline and normal populations shared similar genetic structure with a genetic distance of 0.045. By using a modified procedure of random amplified polymorphic DNA(RAPD), a higher level of DNA diversity was detected in saline populations. The authors propose that the high level of genetic diversity and developmental flexibility is responsi- ble for adaptation of wild soybean to changing saline conditions.