【作者】 张海燕；

【导师】 樊军锋；

【作者基本信息】 西北农林科技大学 ， 林木遗传育种， 2020， 硕士

【摘要】 杨树是我国重要的工业用材、经济绿化树种。杨树资源的高效培育和利用在我国林业产业发展和生态环境保护中具有重要意义。本试验以新引自意大利的3个银白杨无性系、5个欧美杨无性系和其西北地区近亲缘无性系为试验材料进行抗寒性测定分析,测定-15℃--35℃温度梯度下各杨树无性系SOD、POD、CAT保护酶活性、丙二醛含量、可溶性蛋白含量等生理生化指标的变化,结合隶属函数综合评价方法和聚类分析对无性系的抗寒性差异进行比较和排序,为杨树抗寒性研究和新品系的选育推广提供理论依据;以STR荧光检测技术进行杨树无性系的12对SSR引物的扩增结果检测,为各杨树无性系构建指纹图谱,以期为杨树的遗传资源鉴定、选择等奠定基础。对包含新引进杨树无性系在内的白杨派、黑杨派无性系研究表明:1)参照隶属函数综合评价结果对杨树无性系抗寒性排序为:白杨派中A50>秦白杨1号>84K>新疆杨>A46>I-101>毛白杨>A39;黑杨派中Qg>Ta>Pa>Ti>La>中林46>I-107。聚类分析结果表明,强抗寒类型的杨树无性系包括银白杨A50、秦白杨1号、84K、欧美杨Qg、Ta。2)低温胁迫下的生理生化指标变化呈先升高后降低的趋势,符合前人研究结果。6项抗寒性指标间具有不同程度的相关性,依据6项指标建立供试杨树抗寒性评价体系具有一定的可靠性。3)18份杨树无性系的SSR引物平均多态性位点为7.6个,平均有效等位基因数为5.4个,平均Shannon指数(I)为1.8015,平均Nei’s基因多样性指数(H)为0.7948,遗传相似系数变幅在0.549-0.978,表明供试杨树无性系在SSR序列上具有较为丰富的多态性。4)采用12对SSR多态性引物构建出18个杨树无性系的指纹图谱,为其制定独特身份信息。SSR分子标记技术在杨树遗传差异性分析中具有可行性,可为杨树优良无性系选育提供一定的理论依据。更多还原

【Abstract】 The efficient cultivation and utilization of poplar resources plays an important role in China’s forestry industry development and ecological environmental protection as Poplar is an important industrial timber and economic tree species in our country.In this experiment,18 new poplar clones including three newly Populus alba clones,five Populus×euramericana clones from Italy and their close relatives in the northwest region in China were used as test materials.The cold resistance study was carried out using the clones of the Populus tomentosa clones and Populus deltoides clones group.The changes of the protective enzyme activities of SOD,POD,CAT,MDA content and soluble protein content of each poplar clone under a temperature gradient of-15 ℃--35 ℃ were measured.Combining the comprehensive evaluation method of membership function and cluster analysis to compare and rank the cold resistance differences of clones,it provides a theoretical basis for the research of poplar tree cold resistance and the selection and promotion of new strains.The STR fluorescence detection technology was used to detect the amplification results of 12 pairs of SSR primers of poplar clones,and to construct fingerprints for each poplar clone,in order to lay the foundation for identification and selection of poplar genetic resources.The main conclusions of this test are as follows:1)With reference to the comprehensive evaluation results of membership functions of poplar clones,the order of resistance in Populus tomentosa clones to cold is: ‘A50’> ‘Qinbaiyang1hao’> ‘84K’> ‘Xinjiangyang’>‘A46’>‘I-101’> ‘Maobaiyang’> ‘A39’;the order of resistance in Populus×euramericana clones to cold is: ‘Qg’> ‘Ta’> ‘Pa’> ‘Ti’> ‘La’> ‘Zhonglin46hao’> ‘I-107’.The results of cluster analysis show that,the poplar clone group with strong cold resistance includes Populus abla clones ‘A50’,‘Qinbaiyang1hao’,‘84K’,Populus×euramericana clones ‘Qg’,‘Ta’.2)The changes of physiological and biochemical indicators under low temperature stress showed a trend of increasing first and then decreasing,which was in line with the results of previous studies.There are different degrees of correlation among the 6 cold resistance indicators.According to the 6 indicators,the establishment of a poplar cold resistance evaluation system for testing has certain reliability.3)The average SSR primer polymorphism sites of 18 poplar clones are 7.6,the average effective allele number is 5.4,the average Shannon index(I)is 1.8015,and the average Nei’s gene diversity index(H)is 0.7948,the variation range of genetic similarity coefficient is 0.549-0.978,indicating that the tested poplar clones have rich polymorphism in SSR sequence.4)Using 12 pairs of SSR polymorphic primers to construct fingerprints of 18 poplar clones and formulate unique identity information for them.SSR molecular marker technology is feasible in the analysis of poplar genetic differences,and can provide a certain theoretical basis for the selection of poplar clones.更多还原