古银杏雄株的ISSR遗传多样性分析

应用ISSR分析技术对19个省市的97株古银杏雄株进行遗传多样性分析,并对它们的亲缘关系进行分析鉴定。结果表明:银杏雄株具有丰富的基因多样性和遗传多样性,选用的13个引物共扩增出114条DNA条带,其中多态性DNA条带83条,占72.8%;有效等位基因数为1.8117,基因多样度为0.4374,Shannon信息指数为0.6253;利用UPGMA法对扩增结果进行聚类分析,把97株古银杏雄株分为2大类,一类表现出较强的地理相关性,另一大类结果表明遗传距离与地理位置远近不完全相关。     

梨属植物ISSR技术体系的建立与优化

本研究以雪花梨为材料,对ISSR反应体系中的模板用量、引物浓度、dNTPs浓度、TaqDNA聚合酶用量等一些重要参数进行探索和优化,初步建立了稳定的具有广泛适用性的梨属植物ISSR技术的反应体系及扩增程序,即20 μL体系中含1×buffer (内含1.5 mmol? L-1 MgCl2)、模板DNA 40～60 ng、引物浓度为0.2 μmol?L-1、 dNTP 200 μmol?L-1、Taq DNA聚合酶 1U。扩增程序为：94℃ 5 min、退火60s、72℃延伸120 s,然后连续39个循环为94℃ 60s、退火温度(52℃左右)60s 、72℃延伸120s,完成最后一个循环后,在72℃继续延伸10 min,然后在4℃保温,最后通过1.4%的琼脂糖凝胶电泳检测其扩增产物。     

Molecular analyses of genetic variability in soap nut (Sapindus mukorossi Gaertn.)

Sapindus mukorossi Gaertn. (Sapindaceae) is commercially an important plant much valued for its fruits commonly known as soap nut as well as for the seed oil used as a feed-stock for biodiesel production. Molecular polymorphism, determined, using three single primer amplification reaction (SPAR) methods (RAPD, DAMD and ISSR) is used to assess the genetic variability in 69 accessions of S. mukorossi Gaertn., encompassing different geographical regions in India. Cumulative band data generated using the three SPAR methods resulted in 82.49% polymorphism across all genotypes of S. mukorossi Gaertn. UPGMA tree showed two major clusters that were in accordance with the geographical diversity. The intra-population genetic diversity (0.16), Shannon information index (0.24) and polymorphic loci (45.62%) were highest in AS population, while the corresponding lowest values were recorded in HP population. The inter-population average distance ranged from 0.05 (GA and HP) to 0.26 (AP and HP). Based on these distances, the UPGMA tree for the populations was computed, which showed the presence of two major clusters. Cluster I contained all the populations from Himachal Pradesh (HP) and Uttarakhand (GA and KU) and cluster II grouped the populations from North Eastern region (AS, AP, MG). The present study showed that SPAR methods are informative and useful to unravel the diversity among different populations of the soap nut plants and is a prelude for further utilization of promising and genetically divergent materials in the breeding programmes.     

ISSR molecular characterization and leaf volatiles analysis of Pittosporum undulatum Vent. naturalized in the Azores archipelago (Portugal)

Pittosporum undulatum from the Azores archipelago was characterized by both molecular and volatiles analyses. Inter simple sequence repeat (ISSR) evaluation was performed based on a random sampling of 77 individuals from a total of 123 samples collected on all the Azorean islands. Molecular studies grouped the samples mainly according to the geographical collection site, with some exceptions. Leaf volatiles were isolated by distillation-extraction and analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) from all the 123 samples. Cluster analysis based on the leaf volatiles chemical composition defined three main clusters, not related to sample site collection, and was based mainly on the relative amounts of limonene (3-89%), sabinene (0.1-64%) and terpinen-4-ol (traces-43%). Clusters obtained from both molecular studies and volatiles composition were not superimposable and no correlation between ISSR markers and volatile oils could be drawn. The results suggest that there is a high genetic variability among individuals of P. undulatum that can explain the invasive ability of this species in the Azores archipelago. The detailed characterization of this alien weed species may assist finding potential commercial uses as well as management strategies to help its eradication and/or control.     

芒果ISSR反应体系的建立与优化

运用L16(45)正交设计对芒果ISSR反应的5个因素,即DNA模板浓度、Mg2+浓度、dNTPs浓度、引物浓度、Taq DNA聚合酶浓度在4个水平上进行优化试验,通过不同反应体系扩增效果比较,建立优化的芒果ISSR反应体系,即25μL的PCR体系中含有DNA模板25 ng、Mg2+浓度为1.5 mmol/L、dNTPs 0.3 mmol/L、引物0.32μmol/L、Taq DNA聚合酶1.25 U。这为进一步运用ISSR标记在DNA分子水平上对芒果种质资源进行分析奠定基础。     

中国油棕种质材料的遗传多样性研究

为开发利用中国油棕种质资源,从DNA分子水平上对海南和云南油棕种质资源进行遗传多样性研究。应用ISSR技术对海南和云南的85份油棕种质材料进行遗传多样性分析,用23个引物对所有85个新引进油棕种质及原有油棕种质材料进行ISSR扩增,23个引物共扩增出201条带,其中多态性条带占78.6%。聚类分析的结果显示,采自海南、云南的新选育油棕种质及原有的油棕种质材料基本上能按不同的采集地点或不同的来源途径而分别聚类在一起。     

东北地区野豌豆属四个种间遗传关系的ISSR分析

对野豌豆属的山野豌豆、狭叶山野豌豆、广布野豌豆和东方野豌豆4份材料,利用ISSR分子标记进行遗传关系分析。6个引物共扩增出52条带,其中多态性条带总数为46条,平均多态性比率为88.46%。Shannon多样性指数分析结果表明,种内平均遗传多态度为1.72,遗传多态度总量为4.39;种内变异值在0.15~0.72之间,种内的遗传变异均值为0.42;种间的遗传变异均值为0.58。UPGMA法遗传关系聚类显示,山野豌豆和狭叶山野豌豆亲缘关系最近,与东方野豌豆亲缘关系最远。利用ISSR标记技术可较准确分析野豌豆属材料间的亲缘及遗传多样性。     

内蒙古地区草地螟白僵菌不同地区遗传多样性分析

应用ISSR(简单重复序列间隔区)标记对采集自内蒙古3个地区的17株白僵菌(Beauveria Bassiana(Bals.)Vuill.)菌株进行遗传多样性分析,探讨了白僵菌在不同地区之间和地区内部的遗传多样性。结果表明:从21个引物中筛选出15个多态性高、稳定性好的ISSR引物,建立了ISSR的最佳反应体系。在ISSR试验中,15个ISSR引物共扩增出90条带,其中87条为多态性条带,群体多态位点百分率(PPL)为96.67%,Nei’s基因多样性指数(H)为0.4309,Shannon’s信息多样性指数(I)为0.6106。在群体间的遗传相似度聚类分析中,内蒙古中部和西部地区的遗传一致度最高为0.9897,兴安盟地区和鄂尔多斯市地区的遗传一致度最高为0.9621。     

苜蓿褐斑病抗性相关分子标记验证

选取4个具有不同遗传背景的紫花苜蓿(Medicago sativa L.)国内外推广品种为材料,通过人工接种试验每个品种筛选苜蓿褐斑病高抗、高感单株各10株,运用ISSR,AFLP和SRAP分子标记技术对标记适用性进行验证,以期筛选准确性高的分子标记,提高试验的重复性和稳定性。结果表明:4个品种的总体病情指数和抗病性成反比,抗病性大小依次为:赛迪>新疆大叶>中苜一号>龙牧801;且筛选到的高抗、高感单株的抗病性与4个品种的总体抗病性基本相符;适用性高的标记有感病标记ISSR22_S450、抗病标记SRAPM3E3_R169和ISSR20_R750,分子标记检测的符合率在75%～85%之间,可用于苜蓿褐斑病的标记辅助选择育种工作。适用性中等的标记有感病标记IS-SR6_S640和AFLP38_S264,抗病标记AFLP1_R206,AFLP16_R185和ISSR834_R450均在1个品种中显示出差异不显著,仍需在更多品种中验证;适用性差的标记有感病标记ISSR11_S750和ISSR22_S640,不能作为检测苜蓿褐斑病的可靠指标。     

利用ISSR技术分析禾谷镰孢菌群体遗传多样性的研究

采用ISSR标记对采自我国11个省的玉米茎腐病相关禾谷镰孢的遗传多样性进行分析。利用筛选出的14个ISSR引物对供试的115株禾谷镰孢菌株进行扩增,共获得63条扩增清晰、重复性高的条带,其中多态性条带为60条,占95.2%。扩增条带分子量为150～2000bp,平均每个引物扩增出4.5条带。遗传多样性分析表明,在地理种群水平上,基因多样性指数在0～0.2919之间,平均为0.1591;Shannon‘s多样性指数在0～0.4252之间,平均为0.2360,表明不同地理种群间存在一定的遗传变异。多样性指数、等位基因数的增大与各种群内样本数量增加有关。遗传相似性分析证明,山东省种群与河南省种群间的遗传相似性最高,内蒙古种群与河北省种群间遗传相似性最低。在相似性系数为0.682时,可将115个菌株区分为2个聚类组,各组下又可分为3个亚组,分组结果与菌株的地理来源有一定相关性,表明禾谷镰孢的遗传分化与生态地理有关。