【作者】 史万光；

【导师】 王照兰；

【作者基本信息】 甘肃农业大学 ， 草业科学， 2008， 硕士

【摘要】 以充分挖掘利用我国北方广泛分布的达乌里胡枝子种质资源为目的,以中国农业科学院草原研究所筛选到的达乌里胡枝子不同品系及其相关种和种质为试验材料,在已有研究的基础上,采用生态学、形态学、生理学和育种学相结合的实验技术手段,对达乌里胡枝子不同品系进行了品比试验、区域试验、抗逆性鉴定(抗旱、抗盐),以及种子贮藏蛋白遗传多样性和指纹图谱研究。在抗逆性、遗传多样性和指纹图谱等方面还与胡枝子属的其它相关种和种质进行了比较,从多个层面上揭示了达乌里胡枝子4个品系的品系特性。1.根据达乌里胡枝子4个品系的品比试验、区域试验,初步筛选出达乌里胡枝子优秀品系2个,即:达乌里胡枝子品系8号和牛枝子品系11号。8号品系的分枝数多,株丛直径大,叶量大,植株田间表现整齐,干草产量和种子产量均最高,分别为2823.75kg/ha和452.25 kg/ha;11号品系枝条长、丛径大,分枝较多,匍匐型贴地生长,干草产量和种子产量分别达2463.75kg/ha和339.75kg/ha,与8号品系相比其生产性能稍差。2.采用不同浓度梯度的PEG和NaCl分别对达乌里胡枝子4个品系及2个对照种的进行胁迫处理,通过发芽动态、相对发芽率、发芽势、活力指数及半致死浓度综合分析表明:种子萌发期耐旱性和耐盐性顺序均为对照种二色胡枝子13号>品系11号>品系8号>品系9号>品系10号>对照种尖叶胡枝子12号; PEG胁迫的半致死浓度分别为0.84MPa、0.72MPa、0.69MPa、0.66MPa、0.58Mpa和0.41Mpa;NaCl胁迫的半致死浓度分别为5.83%、3.12%、2.6%、1.94%、1.6%和0.78%。3.对达乌里胡枝子4个品系及其相关种和种质在个体和群体两个水平上进行种子贮藏蛋白提取,对其遗传多样性和聚类结果进行分析表明:13份供试材料总基因多样性为0.2785,遗传分化系数(Gst)为0.6325(>0.51),表明63.25%遗传变异存在于供试材料之间,36.75%存在于各供试材料内部。达乌里胡枝子4个品系的总基因多样性为0.1891,遗传分化系数(Gst)为0.4185(<0.51),表明有41.85%的遗传变异存在于各品系之间,58.15%的遗传变异存在于各品系之内。聚类结果显示:供试的13份材料可以聚为4类,1号和13号聚为第一类;2号和3号聚为第二类;4号和12号聚为第三类;其余7份材料聚为第4类。从聚类图反应的系统进化树来看,达乌里胡枝子各种质之间亲缘关系最近,其次是达乌里胡枝子与其变种牛枝子和无梗达乌里胡枝子。而在种级水平上,达乌里胡枝子与尖叶胡枝子亲缘关系较近,其次是截叶胡枝子,与二色胡枝子亲缘关系最远。4.品比试验、区域试验和抗逆性鉴定(抗旱、耐盐)试验结果综合分析表明,供试的达乌里胡枝子8号品系主要农艺性状、生产性能最好、基因多样性指数最高,抗旱性和耐盐性仅次于11号品系牛枝子。而11号品系牛枝子抗旱性和耐盐性最强。二者各有所长,均可优先申报品种。更多还原

【Abstract】 The aim of the study was to well use the germplasm resources of the Lespedeza davurica, which was widely distributed in the north of China. The experimental material was the different lines and the related species and germplasms that were screened by Grassland Research Institute of Chinese Academy of Agricultural Science. On the base of previous studies, using ecology, morphology, physiology and breeding methods, this dissertation did the variety comparative test, regional test, the salt resistance and drought resistance, seed storage protains, genetic diversity and fingerprint in different lines of the Lespedeza davurica. Through compare to the other related species and germplasms on stress resistance, genetic diversity and fingerprint and so on, revealed the lines characteristics of Lespedeza davurica.1. According to the variety comparative and regional test of four lines of Lespedeza davurica, two outstanding lines of Lespedeza davurica be screened out initially that was line 8 and line 11 . The line 8 has many branches , a big clump diameter , many leaves, and the field performance is more uniform. The hay and seed production is 2823.75 kg/ha, 452.25 kg/ha, respectively. Line11 has long branches , more big clump diameter, many branches, its field performance also better, but its hay and seed production is slightly lower than the line 8.2. The stress treatment of the 4 lines and 2 contrast varieties were conducted by PEG and NaCl at different concentration gradient.The comprehensive analysis of the germination dynamic, the relative germination percentage, the germination power, vigor index and the half-lethal density indicated, the drought resistance and salt resistance order of the 6 materials as follows: contrast species13 > line 11 > line 8 > line 9 > line 10 > contrast species12. The half-lethal density of PEG is 0.84Mpa, 0.72Mpa, 0.69Mpa, 0.66Mpa, 0.58Mp, 0.41Mpa, respectively. The half-lethal density of the NaCl stress is 5.83%, 3.12%, 2.6%, 1.94%,1.6%, 0.78%, respectively.3. Extract seed storage proteins of four L. davurica lines and its relative species and germplasms at individual and population levels, analyzed the genetic diversity and result of clusters. The total genetic diversity of 13 materials was 0.2785, genetic differentiation coefficient(Gst) was 0.6325(>0.51), it showed that there were 63.25% genetic variation between the materials, and 36.75% genetic variation in every samples. The total genetic diversity of 4 Lespedeza davurica lines was 0.1891, genetic differentiation coefficient(Gst) was 0.4185(<0.51), it showed that there were 41.85% genetic variation between the lines, and 58.15% genetic variation in every line. Cluster result showed that 13 materials may gather four kinds: 1 and 13 gathered for the first kind; 2 and 3 gathered for the second kind; 4 and 12 gathered for the third kind; other 7 materials(include the four lines) gathered for the 4th kind. The system cladogram which reflect from the genetic distance indicated: lines and germplasms of Lespedeza davurica has the more close sibships.On the species leve, Lespedeza davurica and L. hedysaroides has the more close sibships, next is the L. cuneata, finally is L. bicolor.4. The comprehensive analysis the variety comparative test, regional test , the salt resistance and drought resistance test result indicated: The line8 of Lespedeza davurica has the best agronomic characters and the field performance, the drought resistance and the salt endurance are only inferior to line11. The line 11 of L. davurica var. has better drought resistance and salt resistance than line8. They both has own distinctive trait, may prior be registered variety.更多还原