不同经济类型高粱的RAPD分析

对四种不同经济类型高粱采用ＤＮＡ随机扩增多态技术（ＲＡＰＤ）进行了比较研究。１８种引物扩增后共得到５４个ＲＡＰＤ标记,其中２３个标记在进行４种高粱成对比较时呈多态。根据计算出的遗传距离值可以发现虽然不同种高粱之间差异虽然较小,但仍具有丰富的遗传多样性。     

普通小麦抗、感赤霉病品种(系)的RAPD标记分析

采用RAPD技术,用524个随机引物对3个抗病品种和4个感病品种的基因组DNA进行扩增,发现3个引物能在抗、感品种间检测到稳定的多态性。这3个引物及它们产生的多态片段是S347 1220bp、S372 872bp和S375 1360bp,其中S347 1220bp和S372 875bp在感病品种上呈显性扩增,在抗病品种上无扩增,相反S375 1360bp在感病品种上无扩增,在抗病品种上呈显性扩增。初步判断这3个特异带与小麦赤霉病抗性有关。     

Genetic diversity evaluation of some elite cotton varieties by RAPD analysis

Random amplified polymorphic DNA (RAPD) analysis was used to evaluate the genetic diversity of elite commercial cotton varieties. Twenty two varieties belonging to Gossypium hirsutum L. and one to G. arboreum L. were analyzed with 50 random decamer primers using the polymerase chain reaction (PCR). Forty nine primers detected polymorphism in all 23 cotton varieties, while one produced monomorphic amplification profiles. A total of 349 bands were amplified, 89.1% of which were polymorphic. Cluster analysis by the unweighted pair group method of arithmetic means (UPGMA) showed that 17 varieties can be placed in two groups with a similarity ranging from 81.51% to 93.41%. G. hirsutum L. varieties S-12, V3 and MNH-93 showed a similarity of 78.12, 74.46 and 69.56% respectively with rest of the varieties. One variety, CIM-1100, showed 57.02% similarity and was quite distinct. The diploid cotton G. arboreum L. var. Ravi was also very distinct from rest of its tetraploid counterparts and showed only 55.7% similarity. The analysis revealed that the intervarietal genetic relationships of several varieties is related to their center of origin. As expected, most of the varieties have a narrow genetic base. The results obtained can be used for the selection of possible parents to generate a mapping population. The results also reveal the genetic relationship of elite commercial cotton varieties with some standard “Coker” varieties and the diploid G. arboreum L. var. Ravi (old world cotton). Received: 12 July 1996 / Accepted: 26 July 1996     

Efficiency of phenotypic and DNA markers for a genetic diversity study of alfalfa

Information on genetic diversity and germplasm characterization is essential for successful crop improvement. Diverse data sets (pedigree, morphological, biochemical, DNA based-markers) are employed in various aspects of plant analysis. The objective of this study was to determine the efficiency of phenotypic and RAPD markers in diversity assessment of ten alfalfa (Medicago spp.) accessions from Europe, North America and Australia. Field experiment was designed as a randomised complete block with three replications over two consecutive years (2004, 2005) at one location. Twelve morpho-agronomic traits were recorded on 50 plants per each accession. Genomic DNA’s from 16–20 randomly selected individual plants per accession were used for RAPD analysis. Six primers selected in this study generated a total of 93 polymorphic RAPD bands. The number of polymorphic bands detected per primer ranged from 11 to 20. Genetic distances (GD) among investigated accessions and two-dimensional principal coordinate analysis (2D PCoA) based on phenotypic and molecular data were obtained. The average GD between (0.283–0.416) and within (0.247–0.332) accessions based on RAPD data was higher than GD values obtained by morpho-agronomic traits (0.171–0.354 and 0.157–0.261, respectively). 2D PCoA based on GD from RAPD data grouped most of the studied individual plants to four clusters according to their geographical or taxonomy origin. 2D PCoA based only on morpho-agronomic data did not group plants congruently to their origin, probably due to a strong environmental influence on studied traits. Our results indicated that the RAPD markers were effective in assessing genetic diversity within and between studied alfalfa accessions. In addition, the obtained results suggested that the RAPD markers might be useful for grouping of germplasm with similar genetic background and for pre-screening of potential heterotic groups in our breeding programme.     

Genetic distance detected with RAPD markers among selected Australian commercial varieties and boron-tolerant exotic germplasm of pea (Pisum sativum L.)

The optimisation of polymerase chain reaction (PCR) for random amplified polymorphic DNA (RAPD) analysis in pea was investigated and the results were applied to an analysis of five representative Australian varieties and five selected boron-tolerant accessions derived from different geographical regions. Genotypes were compared using 34 random primers (Operon Technologies, Alameda, CA) which generated 180 polymorphic bands. Genetic similarity among genotypes was estimated on the basis of the percentage of common bands between genotypes and a dendrogram was constructed by the unweighted pair grouping method. A pattern of RAPD reaction corresponding to two main groups was discerned. The genetic divergence between Australian varieties and the boron-tolerant accessions suggests an intensive back-crossing programme would be required to transfer boron tolerance to a locally adapted genetic background. Our results show RAPD to be useful for clarifying phylogenic relationships within a species and also to provide useful genetic markers for varietal identification in pea.     

名贵茶花种质资源的RAPD分析

采用RAPD方法构建了国内外23个茶花品种的指纹图谱。从100个随机引物中筛选出的20个有效引物共产生136条DNA片段,遗传多态性带120条占总数88．2％。遗传相似性分析表明,各基因型间的Nei＇s相似系数分布在0．4386～0．8936之间,平均相似性系数为0．7668。通过非加权算术平均数聚类（UPGMA）法,绘制了它们的遗传关系树状图,23个品种可划分为3个类群。研究结果表明,RAPD技术可用于茶花品种的鉴别以及种质资源遗传多态性的研究。     

Evaluation of the genetic fidelity of in vitro-propagated gerbera (<Emphasis Type="Italic">Gerbera jamesonii</Emphasis> Bolus) using DNA-based markers

The genetic fidelity of in vitro-raised gerbera clones was assessed by using random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) markers. Out of 35 RAPD and 32 ISSR primers screened, only 12 RAPD and 10 ISSR primers produced clear, reproducible and scorable bands. The 12 RAPD primers produced 54 distinct and scorable bands, with an average of 4.5 bands per primer. The number of scorable bands for ISSR primers varied from 3 (ISSR-14) to 9 (ISSR-07), with an average of 5.5 bands per primer. The number of bands generated per primer was greater in ISSR than RAPD. All banding profiles from micropropagated plants were monomorphic and similar to those of the mother plant. A similarity matrix based on Jaccard’s coefficient revealed that the pair-wise value between the mother and the in vitro-raised plantlets was 1, indicating 100% similarity. This confirmed the true-to-type nature of the in vitro-raised clones.     

家蚕不同地理品种分子系统学研

利用随机引物扩增多态性DNA(RAPD)标志,在DNA分子水平上对不同系统、化性和眠性共六类59个家蚕Bombyx mori品种及野蚕且mandarina之间的遗传差异进行了研究。在34个随机引物中有12个(35.29%)引物出现稳定的扩增带,扩增总带数为103条,其中86条具多态性,占83.5%,平均每个引物7.2条。利用单匹配相似系数和UPGMA聚类法对结果进行分析,发现其RAPD不但具有品种特异性,而且具有系统特异性,证明中国一化性四眠种为最早从野蚕中分化出来的系统,中国一化性三眠种与中国一化性四眠种在进化上属有显著差异的两个类群。     

香蕉33个品种的RAPD研究

利用RAPD技术对香蕉（Musa nana Lour.)33个品种的遗传变异进行了研究,从249个随机引物中筛选出18个有效引物,用它们共扩增出192条DNA带,其中183条为多态性带,占95．31％,平均每个引物扩增的DNA带数为10．67条,利用18个有效引物扩增的192条DNA带对香蕉33个品种间的亲缘关系进行UPGMA聚类分析,计算出33个品种间的平均遗传距离为0．3412。在此基础上建立了香蕉33个品种的DNA分子系统树状图。该系统将香蕉33个品种划归A,B,C和D4个群,其中A群20个品种,B群5个品种,C群2个品种,D群6个品种;A群又可以分为3个亚群。对香蕉遗传多样性分子基础进行了探讨。     

Assessment of genetic variation withinBrassica campestris cultivars using amplified fragment length polymorphism and random amplification of polymorphic DNA markers

Genetic relationships were evaluated among nine cultivars ofBrassica campestris by employing random amplification of polymorphic DNA (RAPD) and amplified fragment length polymorphism (AFLP) markers. RAPDs generated a total of 125 bands using 13 decamer primers (an average of 9.6 bands per assay) of which nearly 80% were polymorphic. The per cent polymorphism ranged from 60–100%. AFLP, on the other hand generated a total of 319 markers, an average of 64 bands per assay. Of these, 213 were polymorphic in nature (66.8%). AFLP methodology detected polymorphism more efficiently than RAPD approach due to a greater number of loci assayed per reaction. Cultivar-specific bands were identified, for some cultivars using RAPD, and for most cultivars with AFLP. Genetic similarity matrix, based on Jaccard’s index detected coefficients ranging from 0.42 to 0.73 for RAPD, and from 0.48 to 0.925 for AFLPs indicating a wide genetic base. Cluster analyses using data generated by both RAPD and AFLP markers, clearly separated the yellow seeded, self-compatible cultivars from the brown seeded, self-incompatible cultivars although AFLP markers were able to group the cultivars more accurately. The higher genetic variation detected by AFLP in comparison to RAPD was also reflected in the topography of the phenetic dendrograms obtained. These results have been discussed in light of other studies and the relative efficiency of the marker systems for germplasm evaluation.