新麦草Psathyrostachys juncea遗传变异的细胞学和分子的分析

本文用染色体C分带、同功酶和RAPD技术分析了来自不同地理分布的新麦草不同材料的单株,观察其c带的多态性,即同源染色体的配对,相同材料的不同个体之间,同一地区不同材料之间,以及不同来源的材料之间的多态性。10个同功酶揭示了14个假定标记位点,其中11个显示了多态性(平均66.2％,每个位点具2.6个等位基因)。大量的等位变化发生在多数的多态位点上。在所用试材中有近90％的等位变化。在优化条件下,200个测试引物中有55.5％的材料间产生了多态性的RAPDs带型。在同一材料中和不同材料间分别有55.7％和47.8％的扩增片断是多态的。C—带、同功酶和RAPD分析结果是互相确证而高度一致的,为新麦草的遗传变异提供了模式。 新麦草具有抗旱、耐盐碱和抗黄矮病的特性,可以在小麦育种工作上加以利用。

Cytological and Molecular Analyses of Genetic Variation in Psathyrostachys juncea

Psathyrostachys juncea is a potential source of a number of useful genes for wheat improvement, including barley yellow dwarf virus(BYDV)resistance, salt tolerance, drought tolerance.Individuals in different accessions of Russian wildrye(Psathyrostachys juncea)collected from different geographical regions were analyzed with C-banding, isozyme and RAPD techniques. C-banding polymorphisms were observed at all levels, i. e. , within some homologous chromosome pairs, among different individuals in the same accession, between different accessions of the same geographic area, and among accessions of different origins. Ten enzymes revealed 14 putative and scorable loci, of which 11 showed poly-morphisms(on average, 66. 2% loci polymorphisms and 2. 6 alleles per locus). A large amount of allelic diversity occurred at most polymorphic loci. Approximately 90% of the allelic diversity existed within accessions. Under the optimized condition, 55. 5% of the 200 tested primers produced polymorphic RAPDs among accessions. 55. 7% and 47. 8% of the amplified fragments are polymorphic within and among accessions, respectively. The results from C-banding, isozymes and RAPD were highly corroborated and provided the pattern of genetic variation in Russain wildrye.