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摘要：多伦多论文-披碱草、老芒麦及其杂交后代的遗传研究-加拿大披碱草与老芒麦均为披碱草属植物,二者的抗逆性和适应性强,综合生产性能好,适合作为远缘杂交的原始材料。我国生态建设和畜牧业发展急需耐寒、耐旱、产量高的优质牧草品种,因此培育牧草新品种具有重要意义,而远缘杂交育种是从根本上改良牧草的有效手段。本文以加拿大披碱草、老芒麦、杂种F1、F1加倍当代株系Ⅰ（C0Ⅰ）、F1加倍一代Ⅰ（C1Ⅰ）、F1加倍当代株系Ⅱ（C0Ⅱ）和F1加倍一代Ⅱ（C1Ⅱ）为材料,从数量遗传学、细胞学、生化标记和RAPD分子标记四个层次对加拿大碱草与老芒麦及其杂交后代进行了遗传分析,为选择优良单株提供依据,为培育优质的牧草新品种奠定基础。

多伦多论文-披碱草、老芒麦及其杂交后代的遗传研究-The genetic relationships among E.canadansis, E.sibiricus and its hybrids were studied by quantitative characters,isozyme,cytology and RAPD markers.Results were as follows:1 F1 was pure hybrid by EST isozyme and RAPD.Hybrids of E.canadensis and E.sibiricus were inclined to female parent E. canadansis. C1Ⅱwas from F1.C1Ⅱpopulation was classified into three cluster by clustering analysis.One cluster was inclined to female parent;The other was inclined to male parent;Another was intermediate.2 Somatic chromosome number of C0Ⅱ,C1Ⅱand C1Ⅰwas 42 respectively,which was proved that the three kind of plants were originated from F1. The hybrids were analysized by karyotype .Results verify the truth of F1. But the structure of chromosome of hybrid F1 were different from parents. We deduced the original of some F1 chromosome by the chromosome parament.

Results show No.of 8、9、11、12、13、14 chromosome of F1 were originated from No.of 9、10、11、12、13、14 of male parent E.sibiricus.C0Ⅰchromosome were almost were originated from F1. Compared with C0Ⅰ,C1Ⅰchromosome decreased 14 chromosomes .3 The hybrids were super to their parents in many agronomic characters,for example, growing periods,growth vigour ,height of plant,grass yield,leaf width and length and No.of tiller. Diameter of stem and No.of internode.4 Seven agronomic quantitatives traits were analyzed by genetic model of additive dominance and its interaction with enviorerment by QTwin-0.8-appraches. The results indicated that height of plant was mainly controlled by additive interaction with enviorerment effects and dominant interaction with enviorerment effects.

Tiller , Diameter of stem , No.of internode, leaf width , leaf length and No.of spitelet were selected in early generation .because they were mainly controlled by additive effect. Grass yield and length of spite were mainly controlled by dominant effect.5 Fertility of pollen of F1,C1Ⅰand C1Ⅱwas so poor that they were pollen abortion.As a result their seed setting rate were very poor.

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Meiosis of pollen mother cells of C1Ⅰand C1Ⅱpaired disorder, chromosome breakage and lagging chromosome was found. 6 Isozyme zymogram of EST,POD and SOD indicated that zymogram of EST,POD were different in different growth period.But there was no difference among zymogram of SOD.7 RAPD marker indicated that specific band could be seen in hybrids by PCR. Genetic distance among bybrids was very close.But Genetic distance between hybrids and female parent was closer than that of male parent