【作者】 刘志华；

【导师】 于卓；

【作者基本信息】 内蒙古农业大学 ， 作物栽培学与耕作学， 2009， 博士

【摘要】 罗布麻(Apocynum venetum Linn.)为多年生植物,具有耐盐碱、干旱、酷暑、寒冷、贫瘠等优良抗性。罗布麻用途广泛,可药用、也是良好的饲用、纤维、绿化和蜜源植物。目前,我国北方地区罗布麻由于生态环境恶化及人为过度利用,资源量锐减,如何保护和合理利用罗布麻种质资源已成为一项重要的研究课题。本试验对内蒙古地区野生罗布麻的形态性状、AFLP、ISSR及染色体数目和POD同工酶表型进行了遗传多样性分析,旨在明确该地区罗布麻种质资源的多样性状况及亲缘关系,为其合理开发利用提供依据。主要结果如下:1.内蒙古通辽、包头、巴彦淖尔3个地区罗布麻的株高、茎粗、节间长、分枝长、花序长、果荚长、种子长、叶片、长宽等16个表型性状的总多样性指数为1.858,居群内多样性指数为0.862,居群间的多样性指数为0.996,居群内遗传多样性为46.39%,居群间遗传多样性为53.61%。罗布麻不同形态性状的多样性指数差异较大,其中株高、茎粗、节数、节间长、分枝长、千粒重、种子宽、果荚长、顶花序长、花萼长、托叶长、叶长、叶宽的多样性指数较高,容易受到环境的影响,是引起形态变异的主要性状。2.内蒙古3个地区罗布麻形态性状聚类结果:通辽地区单独列为1类,包头地区和巴彦淖尔地区为另1类,包头地区与巴彦淖尔地区的罗布麻亲缘关系较近。3.内蒙古3个地区45份罗布麻材料的DNA扩增得到5359个AFLP位点,多态性位点比例为91.22%。罗布麻AFLP遗传多样性指数为1.286,居群内为0.533,居群间为0.753,居群内的分化系数为41.45%,居群间的分化系数为58.55%,居群内和居群间的变异均为罗布麻种质变异的主要来源。3个不同地区罗布麻的相异系数变幅为0.0042～0.819,以相异系数值0.13为基准,通辽地区的绝大部分材料聚为1类,包头和巴彦淖尔地区的绝大部分材料聚为1类,通辽地区罗布麻种质资源与包头和巴彦淖尔地区的亲缘关系较远。4.利用6个ISSR适宜引物扩增出65个ISSR位点,多态性位点55个,多态性位点比例为84.62%。内蒙古地区罗布麻ISSR遗传多样性指数为0.424,居群内为0.197,居群间为0.227,居群间的遗传分化系数为53.54%。以相异系数0.44为基准分为2类:通辽地区的种质材料聚为1类,地理位置相距较近的巴彦淖尔地区和包头地区的种质材料聚为另1类,包头和巴彦淖尔地区罗布麻种质资源的亲缘关系较近。5.内蒙古通辽地区的染色体数目为20条(2n=2x=20),包头和巴彦淖尔地区的染色体数目均为16条(2n=2x=16),内蒙古东西部地区罗布麻染色体数目存在差异。6.内蒙古通辽、巴彦淖尔、包头3个地区罗布麻苗期叶、茎、根不同器官的POD同工酶酶谱表型存在一定差异,遗传多样性较丰富。更多还原

【Abstract】 As an perennial plant, Apocynum venetum Linn. is well known for its high resistance to salinity, drought, heat and leanness as well as being wildly used as medicine, fiber, ornamental plant, forage and nectariferous plant. Currently, Apocynum venetum Linn. resources in north China have been decreasing sharply owing to the environmental deterioration and abuse of human being, therefore, how to preserve and reasonably utilize Apocynum venetum Linn. resources turns into an important research topic. In this dissertation, the genetic diversity of wild Apocynum venetum Linn. in Inner Mongolia was analyzed based on morphological characteristics, AFLP, ISSR, chromosome number and POD isoenzyme phenotype to confirm the diversity of Apocynum venetum Linn. germplasm and their genetic relationship in this region, and thereby to set up the background for reasonable exploitation and utilization of Apocynum venetum Linn.. The results showed that:1. The total diversity index, diversity index within population, diversity index among populations, genetic diversity within and among populations were 1.858, 0.862, 0.996, 46.39% and 53.61%, respectively, which derived from 16 phenotypic values including plant height, stem thickness, internode length, branch length, inflorescence length, pod length, seed length, leaf length and leaf width of Apocynum venetum Linn.populations originated from Tongliao, Baotou and Bayannaoer. There were big differences among the diversity index of morphological parameters in Apocynum venetum Linn.. The higher diversity index was observed in plant height, stem thickness, node number, internode length, branch length, thousand-seed weight, seed width, pod length, top inflorescence length, calyx length, stipule length, leaf length and leaf width, indicating that these were the major characteristics giving rise to the morphological variance and were readily affected by the environment.2. The clustering of populations of Apocynum venetum Linn. originating from 3 regions of Inner Mongolia based on morphological properties showed that populations of Apocynum venetum Linn. from Tongliao was classified into one group while Apocynum venetum Linn. from Baotou and Bayannaoer belonged to another group, indicating that there was close relationship between Apocynum venetum Linn. populations from Baotou and Bayannaoer.3. 5359 AFLP loci were found by DNA amplification with 45 Apocynum venetum Linn. populations from 3 regions, with 91.22% polymorphic loci. AFLP genetic diversity index, AFLP genetic diversity index within population, AFLP genetic diversity index among populations, differentiation coefficient within population and differentiation coefficient among populations were 1.286, 0.533, 0.753, 41.45% and 58.55%, respectively. The variance of Apocynum venetum Linn. germplasm was mainly derived from variance within population and among populations. Coefficient of difference in Apocynum venetum Linn. from 3 regions varied between 0.0042 and 0.819. Regarding coefficient of difference as a benchmark, most of Apocynum venetum Linn. populations from Tongliao region were sorted into one group while most of Apocynum venetum Linn. populations from Baotou and Bayannaoer were categorized to another group, showing that the relationship between Tongliao group and Baotou group was wide.4. 65 ISSR loci, 55 polymorphic loci were observed by amplification using 6 ISSR primers. 84.62% were polymorphic loci. ISSR genetic diversity index, ISSR genetic diversity index within population, ISSR genetic diversity index among population and genetic differentiation coefficient were 0.424, 0.197, 0.227 and 53.54%, respectively. Regarding coefficient of difference as a benchmark, Apocynum venetum Linn. populations from Tongliao was classified into one group, while Apocynum venetum Linn. populations from Baotou and Bayannaoer came to another group, indicating there was close relationship between Apocynum venetum Linn. populations from Baotou and Bayannaoer.5. 20 (2n =2x =20) chromosomes were observed in Apocynum venetum Linn. from Tongliao while 16(2n =2x =16) chromosomes in Apocynum venetum Linn. from Baotou and Bayannaoer. This result demonstrated that there was difference in chromosome number among Apocynum venetum Linn. populations from west to east of Inner Mongolia.6. POD isoenzyme phenotypic zymograms at different organs (leaf, stem and root) showed some differences among Apocynum venetum Linn. populations originated from 3 different regions.更多还原