首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Murraya koenigii (L.) Spreng. (Rutaceae), is an aromatic plant and much valued for its flavor, nutritive and medicinal properties. In this study, three DNA fingerprinting methods viz., random amplification of polymorphic DNA (RAPD), directed amplification of minisatellite DNA (DAMD), and inter-simple sequence repeat (ISSR), were used to unravel the genetic variability and relationships across 92 wild and cultivated M. koenigii accessions. A total of 310, 102, and 184, DNA fragments were amplified using 20 RAPD, 5 DAMD, and 13 ISSR primers, revealing 95.80, 96.07, and 96.73% polymorphism, respectively, across all accessions. The average polymorphic information content value obtained with RAPD, DAMD, and ISSR markers was 0.244, 0.250, and 0.281, respectively. The UPGMA tree, based on Jaccard’s similarity coefficient generated from the cumulative (RAPD, DAMD, and ISSR) band data showed two distinct clusters, clearly separating wild and cultivated accessions in the dendrogram. Percentage polymorphism, gene diversity (H), and Shannon information index (I) estimates were higher in cultivated accessions compared to wild accessions. The overall high level of polymorphism and varied range of genetic distances revealed a wide genetic base in M. koenigii accessions. The study suggests that RAPD, DAMD, and ISSR markers are highly useful to unravel the genetic variability in wild and cultivated accessions of M. koenigii.  相似文献   

2.
Calamus tenuis (Roxb.), a versatile, dioecious rattan species predominant in northeast India, has emerged as an economical material for light furniture and cottage industries. For the genetic improvement of the species, it is essential to be able to recognize male and female plants at the seedling stage. Screening of genomic DNA with inter-simple sequence repeat (ISSR) primers was used to discover sex-specific polymerase chain reaction (PCR) amplification products. Thirty ISSR primers were screened on female and male C. tenuis plants from five different provinces of Assam, India. A putative female-specific marker was identified. The applicability of ISSR-PCR analysis for development of sex-linked molecular markers in Calamus is discussed.  相似文献   

3.
 Inter-simple sequence repeat (ISSR) amplification was used to analyze microsatellite motif frequency in the rice genome and to evaluate genetic diversity among rice cultivars. A total of 32 primers, containing different simple sequence repeat (SSR) motifs, were tested for amplification on a panel of 59 varieties, representative of the diversity of cultivated rice (Oryza sativa L.). The ISSR analysis provided insights into the organization, frequency and levels of polymorphism of different simple sequence repeats in rice. The more common dinucleotide motifs were more amenable to ISSR analysis than the more infrequent tri-, tetra- and penta-nucleotide motifs. The ISSR results suggested that within the dinucleotide class, the poly(GA) motif was more common than the poly(GT) motif and that the frequency and clustering of specific tri- and tetra-nucleotide simple sequence repeats was variable and motif-specific. Furthermore, trinucleotide ISSR markers were found to be less polymorphic than either dinucleotide or certain tetranucleotide ISSR markers, suggesting which motifs would be better targets for microsatellite marker development. The ISSR amplification pattern was used to group the rice genotypes by cluster analysis. These results were compared to surveys of the same varieties for amplified fragment length polymorphism (AFLP), restriction fragment length polymorphism (RFLP) and isozyme markers. The ISSR fingerprint could be used to differentiate the genotypes belonging to either Japonica or Indica sub species of cultivated rice and to dissect finer levels of diversity within each subspecies. A higher percentage of polymorphic bands was produced with the ISSR technique than the AFLP method, based on a similar PCR reaction. Therefore, ISSR amplification proved to be a valuable method for determining genetic variability among rice varieties and for rapidly identifying cultivars. This efficient genetic fingerprinting technique would be useful for characterizing the large numbers of rice accessions held in national and international germplasm centers. Received: 25 May 1998 / Accepted: 17 September 1998  相似文献   

4.
小苍兰种质遗传多样性的ISSR分析   总被引:6,自引:5,他引:1  
利用ISSR(Inter Simple Sequence Repeat)分子标记对12份小苍兰(Freesia refracta)种质进行了遗传多样性分析研究。从34条ISSR引物中筛选出了12条适宜的引物。这12条引物中每条引物可扩增出5~11条DNA片段,共扩增了96个条带,其中多态性片段62条,平均每条引物可产生5.2条多态性片段,多态性条带比率(PPB)为64.6%。经NTSYS-pc分析,12份小苍兰种质间的遗传距离(GD)的变化范围为0.123~0.907,平均为0.442。根据Nei’s相似系数建立了UPGMA聚类图,在相似系数为0.56时,可将紫色花系的小苍兰种质与其它种质分开,形成两个组。结果表明,ISSR分子标记可有效地分析小苍兰种质资源的遗传多样性和亲缘关系,为小苍兰的杂交育种和新品种保护提供理论基础。  相似文献   

5.
Inter simple sequence repeat (ISSR) and simple sequence repeat (SSR) markers were used to assess the genetic diversity of 36 pineapple accessions that were introduced from 10 countries/regions. Thirteen ISSR primers amplified 96 bands, of which 91 (93.65%) were polymorphic, whereas 20 SSR primers amplified 73 bands, of which 70 (96.50%) were polymorphic. Nei’s gene diversity (h = 0.28), Shannon’s information index (I = 0.43), and polymorphism information content (PIC = 0.29) generated using the SSR primers were higher than that with ISSR primers (h =  0.23, I = 0.37, PIC = 0.24), thereby suggesting that the SSR system is more efficient than the ISSR system in assessing genetic diversity in various pineapple accessions. Mean genetic similarities were 0.74, 0.61, and 0.69, as determined using ISSR, SSR, and combined ISSR/SSR, respectively. These results suggest that the genetic diversity among pineapple accessions is very high. We clustered the 36 pineapple accessions into three or five groups on the basis of the phylogenetic trees constructed based on the results of ISSR, SSR, and combined ISSR/SSR analyses using the unweighted pair-group with arithmetic averaging (UPGMA) method. The results of principal components analysis (PCA) also supported the UPGMA clustering. These results will be useful not only for the scientific conservation and management of pineapple germplasm but also for the improvement of the current pineapple breeding strategies.  相似文献   

6.
Microsatellite loci were identified from chickpea (Cicer arietinum L.), the third most important grain legume crop in the world. A total of 13 sequence‐tagged microsatellite markers were developed using two different approaches: (i) amplification using degenerate primers and (ii) cloning of intersimple sequence repeat (ISSR)‐amplified fragments. Thirty‐five chickpea accessions were analysed, which resulted in a total of 30 alleles at the 13 loci. The observed heterozygosity ranged from 0.1143 to 0.4571 with an average of 0.2284. The cross‐species transferability of the sequence‐tagged microsatellite site (STMS) markers was checked in Cicer reticulatum, the wild annual progenitor of chickpea. These microsatellite markers will be useful for assessing the genetic diversity patterns within chickpea as well as aid in construction of intra‐ and interspecific genetic linkage maps.  相似文献   

7.
Flavoparmelia caperata (L.) Hale is medicinally very important and possesses antifungal and antibacterial activities. F. caperata is the only species found in India. Inter simple sequence repeat (ISSR) and Directed amplification of minisatellite DNA (DAMD) methods were used to analyze the genetic variability within F. caperata from the Western Himalayan region of India. Eleven ISSR and 10 DAMD primers produced 139 and 117 polymorphic bands, and detected 91.44 and 82.34 % polymorphisms, respectively. Cumulative band data generated for ISSR and DAMD markers resulted in 86.86 % polymorphism across all the accessions of F. caperata. The average Polymorphic information content (PIC) value obtained with ISSR, DAMD, and cumulative band data were 0.28, 0.27, and 0.27, respectively. The clustering of the F. caperata accessions in the UPGMA dendrogram showed that these accessions are intermingled with each other in different subclusters irrespective of their geographical affiliations. The pattern of genetic variations within F. caperata accessions could be due to free exchange of spores that might have taken place among these accessions in the wild. ISSR and DAMD markers efficiently and reliably resulted in discrete banding patterns and polymorphic profiles. These markers despite targeting different regions of genome, revealed almost similar levels of polymorphism across all the accessions. The wide range of genetic distance and high level of polymorphism detected by ISSR and DAMD reflected a high genetic variability among the different accessions of F. caperata.  相似文献   

8.
Inter simple sequence repeat (ISSR) marker assay was employed to validate the genetic fidelity of Swertia chirayita plantlets multiplied in vitro by axillary multiplication upto forty-two passages. Sixteen ISSR primers generated a total of 102 amplicons among the tissue-cultured plants. Forty-eight amplicons were amplified in the outlier (a Swertia species). The outlier (negative control) was employed to rule out the possibility that the invariant fingerprint was due to chance alone and that the ISSR technique employed was not discriminatory enough to detect the off-types. A homogenous amplification profile was observed for all the micropropagated plants. The results confirmed the clonal fidelity of the tissue culture-raised S. chirayita plantlets and corroborated the fact that axillary multiplication is the safest mode for multiplication of true to type plants.  相似文献   

9.
Genetic variation in 55 accessions of Cynodon dactylon was estimated using inter-simple sequence repeat (ISSR) markers. The plant materials used in this study originated from 17 countries. A total of 236 ISSR fragments were generated with 14 primers. Fragment sizes ranged from 200 to 3000 bp. All scorable bands were polymorphic in nature and none of the primers used produced monomorphic bands, indicating a high level of genetic variation in this grass. The accessions were found to be clustered into eight major groups through the unweighted pair-group method with arithmetic averages. Genetic similarity coefficients (GSC) among the 55 accessions ranged from 0.52 to 0.95. The results clearly indicate that a high level of variation exists in Cynodon accessions. This study shows that the ISSR technique is a reliable tool for differentiating Cynodon accessions and for determining the genetic relationships among them.  相似文献   

10.
We investigated the genetic variation within 32 accessions distributed to 14 species and one variety by using ISSR (inter-simple sequence repeat) markers. The results showed that genetic variation was relatively higher among the accessions. A total of 593 bands were amplified by 12 ISSR primers, of which 535 bands (90.2%) were polymorphic. Eleven to 80 polymorphic bands were amplified from each prime, with an average of 44.6 bands. The interspecies GS (genetic similarity) value ranged from 0.430 to 0.866, and the average was 0.620. Cluster analysis showed that all accessions could be classified into 4 groups by ISSR markers. The different accessions in a species were clustered together, but they had genetic variation in molecular levels. There was obvious interspecies genetic variation. Species with similar morphological characteristics and from the same areas or neighboring geographical regions were clustered together and had close relationships. ISSR markers are useful in analyzing interspecies variation in Kengyilia. __________ Translated from Guihaia, 2006, 26 (4): 375–380 [译自: 广西植物]  相似文献   

11.
Prosopis cineraria, an important multipurpose tree and vital component of the otherwise fragile ecosystem of arid and semiarid regions of India. It is highly drought tolerant and sprouts profusely during the extreme dry summer months when most other trees are leafless. P. cineraria is known to exhibit comparable genetic variations at intra-specific and inter-population levels reflected through morphological and cytogenetical diversity in regions, where this plant grows naturally. In the present study, single primer amplification reaction (SPAR) methods have been used for determination of diversity at DNA level in 30 accessions of P. cineraria collected from different districts of Rajasthan. The analyses include the use of six minisatellite core sequence primers for direct amplification of minisatellite DNA (DAMD), eight inter simple sequence repeats (ISSR) and 20 arbitrary primed decamer sequences for random amplification (RAPD) reactions. Upon analysis of the data generated, all the three SPAR methods, either independently and/or in combination, revealed wide range of genetic variation among accessions. Comparison of matrix of individual SPAR method using MxComp component of NTSYS-pc 2.02 K software proving that analysis of natural genetic variation using combination of SPAR methods particularly ISSR and DAMD, rather than an isolated approach, is very effective. Such an approach also yields better information and reflection of the relatedness and affinities at intra-species and inter-population levels. Therefore, it is opined that in order to reveal the intrinsic intra-specific variation, SPAR approaches involving more than one DNA marker may reveal more authentic genetic variation in tropical tree species like P. cineraria.  相似文献   

12.
Inter-simple sequence repeat (ISSR) analysis was for the first time used to study the genetic diversity and phylogenetic relationships in 54 wild accessions and cultivars of the genus Lycopersicon. Analysis involved 14 ISSR primers homologous to microsatellite repeats and containing additional selective anchor nucleotides. In total, 318 ISSR fragments were amplified for the wild and cultivated tomato genomes. The interspecific polymorphism revealed with the ISSR primers was 95.6%. Species-specific ISSR fragments were detected for each tomato species. The highest number (more than 20) of species-specific fragments were obtained for L. esculentum sensu lato, although the intraspecific variation of ISSR patterns was low. UPGMA cluster analysis was used to construct a dendrogram and to estimate the genetic distances between the species of the genus Lycopersicon; between populations ofL. peruvianum, L. pimpinellifolium, and L. esculentum; and between tomato cultivars. The ISSR-based phylogeny was generally consistent with Lycopersicon taxonomy based on morphological and molecular evidence, suggesting the applicability of ISSR analysis for genotyping and phylogenetic studies in tomato.  相似文献   

13.
Utilizing intersimple sequence repeat (ISSR) markers, 18 mulberry (Morus spp.) germplasm collections were studied for genetic variability, phylogenetic relationship, and association with protein and sugar content. The genetic polymorphism exhibited by ISSR primers was 100%, and the genetic diversity recorded among the mulberry accessions had an average of 0.263 ± 0.094. Dendrogram (unweighted pair group method analysis) clustered the mulberry accessions into two major groups, one comprised the accessions collected from north or northeast regions of India, and the other comprised three subclusters and one isolate, i.e., Assamjati, a collection from Assam. Another subcluster contained accessions collected from Kerala, which belong to Morus indica. These accessions of M. indica from Kerala were found to be genetically diverse from north and northeast India. Multidimensional scaling of the ISSR data clearly separated the mulberry accessions according to their genetic diversity and protein content. Mulberry accessions were arbitrarily grouped into three classes viz. very low, moderate, and high in terms of protein and sugar content using standard statistical programs. Stepwise multiple regression analysis identified four ISSR markers (8351,600, 8355,600, 8222,500, and 8072,500) associated with protein content with highly positive correlation (p < 0.001) with linear curves with high F values (18.055 to 48.674; p < 0.001). In case of sugar content, four ISSR markers viz. 812900, 8171,500, 8261,500, and 8108,000 showed negative correlation. Hence, DNA markers for proteins seem promising and may be used in marker-assisted breeding program.  相似文献   

14.
 Inter-simple sequence repeat polymorphic DNA (ISSR) was evaluated for its applicability as a genetic marker system in wheat. PCR was carried out with primers that annealed to simple sequence repeats. The resultant products were subjected to agarose-gel electrophoresis, and the banding patterns were compared among six wheat accessions containing diploid, tetraploid, and hexaploid members. Out of 100 examined, 33 primers produced distinguishable as well as polymorphic bands in each of the six accessions. Although most of the primers that gave distinct bands (30 primers out of 33) contained dinucleotide repeats, each of the primers with tri-, tetra-, and penta-nucleotide motifs also yielded discrete bands. Primers based on (AC)n repeats gave the most polymorphic bands. In total, 224 polymorphic bands were found in the comparison between Einkorn wheats whereas, on the average, 120 polymorphic bands were detected between common wheats. ISSR primers produced several times more information than RAPD markers. The extent of band polymorphism was similar to that of RFLP markers, and greater than that of RAPDs. The genetic relationships of wheat accessions estimated by the polymorphism of ISSR markers were identical with those inferred by RFLP and RAPD markers, indicating the reliability of ISSR markers for estimation of genotypes. These polymorphic bands are potential candidates as novel markers for use in linkage-map construction in wheat. The characteristic features of ISSR markers, i.e. polymorphism, generation of information and ease of handling, suggest their applicability to the analysis of genotypes as well as to the construction of PCR-based genome maps of wheats. Received: 15 September 1996 / Accepted: 25 October 1996  相似文献   

15.
Inter-simple sequence repeat (ISSR) analysis was evaluated for its usefulness in generating markers to extend the genetic linkage map of Citrus using a backcross population previously mapped with restriction fragment length polymorphism (RFLP), random amplified polymorphic DNA (RAPD) and isozyme markers. ISSR markers were obtained through the simple technique of PCR followed by analysis on agarose gels, using simple sequence repeat (SSR) primers. Optimization of reaction conditions was achieved for 50% of the SSR primers screened, and the primers amplified reproducible polymorphic bands in the parents and progeny of the backcross population. Mendelian segregation of the polymorphic bands was demonstrated, with an insignificant number of skewed loci. Most of the SSR primers produced dominant loci; however co-dominance was observed with loci derived from three primers. A new genetic map was produced by combining the segregation data for the ISSR markers and data for the RFLP, RAPD and isozyme markers from the previous map and creating genetic linkages among all the markers using JoinMap 2.0 mapping software. The new map has an improved distribution of markers along the linkage groups with fewer gaps, and marker order showed partial or complete conservation in the linkage groups. The incorporation of ISSR markers into the genetic linkage map demonstrates that ISSR markers are suitable for genetic mapping in Citrus. Received: 3 February 2000 / Accepted: 12 May 2000  相似文献   

16.
Inter-simple sequence repeat (ISSR) amplification was evaluated for its applicability as a genetic marker system to establish relationships among ten Diplotaxis species. ISSR amplification generated multiple banding profiles with the 12 primers from all DNA samples, with an average of 41.2 fragments per primer. This average was clearly higher for the 5′ triple-anchored primers than for other primers. The banding profiles were highly repeatable across separate PCR runs. DNA mixing procedures were found to be appropriate strategies to generate banding patterns representative of each species studied. Similarity values were calculated considering 494 ISSR bands, and a dendrogram was constructed based on the similarity matrix. The ten Diplotaxis species were clustered into two major groups. The first group consists of five species, Diplotaxis tenuifolia and Diplotaxis cretacea, and Diplotaxis muralis with their putative parents (D. tenuifolia and Diplotaxis viminea). In the second group three species are clustered that are closely related (Diplotaxis virgata, Diplotaxis catholica and Diplotaxis siettiana), in addition to Diplotaxis harra, and Diplotaxis erucoides, which has lowest similarity values with the rest of the species studied. The two groups defined in the present work may be concordant with the idea suggested by several authors of a biphyletic origin for Diplotaxis. The genetic relationships among the ten Diplotaxis species estimated by the polymorphism of ISSR markers are in agreement with those previously inferred by other morphological, biochemical and molecular data, indicating the reliability of the ISSR approach for this purpose. Received: 3 January 2000 / Accepted: 31 March 2000  相似文献   

17.
Olea europaea L. is one of the most economically important crops in the Mediterranean area, and known for having large genetic variability. In order to assess the genetic diversity, DNA from 41 olive cultivars, present in the protected denomination of origin (PDO) region of Trás-os-Montes, was screened using inter simple sequence repeat (ISSR) and microsatellite (SSR) markers. Eleven ISSR primers amplified 135 reproducible bands of which 108 were polymorphic. The percentage of polymorphic bands detected by ISSR was 79%. The highest number of polymorphic bands was obtained by the use of primers UBC807 (15) and UBC809 (16). A total of 67 alleles were detected by six SSR primers, with an average of 11 alleles per primer. The number of alleles per locus ranged from five (ssrOeUaDCA05) to 15 (ssrOeUaDCA03). The observed heterozygosity ranged from 0.219 (ssrOeUaDCA05) to 0.900 (ssrOeUaDCA04), while the expected heterozygosity varied between 0.426 (ssrOeUaDCA05) and 0.887 (ssrOeUaDCA03). The polymorphism information content (PIC) values ranged from 0.392 (ssrOeUaDCA05) to 0.863 (ssrOeUaDCA03). The collection of primers selected gave a reasonable number of amplification products for the genetic diversity analysis. Based on the results, the genetic diversity among 41 olive cultivars is discussed. This study reveals the great importance of guaranteeing the differentiation of olive cultivars and their application for certification purposes.  相似文献   

18.
Arthrocnemum macrostachyum, is a perennial halophytic shrub typical of Mediterranean salt marshes. The present study aims to investigate some combinations of inter simple sequence repeat (ISSR) and random amplified polymorphic DNA (RAPD) primers applied in real PCR. Thereby, the potential of R-ISSR markers to detect new genomic loci in 3 genotypes of A. macrostachyum grown in the Western coast of Syria was examined. Different combinations of RAPD and ISSR primers produced bands that were absent when single ISSR or RAPD primers were used. The results have demonstrated that ISSR primer (AG)8TC gave more informative pattern when combined with different RAPD primers comparing to other tested primers. In contrast, the tested ISSR primer (GACA)4 gave less informative pattern when used alone. These combinations were successfully applied in real PCR to detect new genomic variability in A. macrostachyum genotypes.  相似文献   

19.
Genetic variation within and between five populations of Oryza granulata from two regions of China was investigated using RAPD (random amplified polymorphic DNA) and ISSR (inter-simple sequence repeat amplification) markers. Twenty RAPD primers used in this study amplified 199 reproducible bands with 61 (30.65%) polymorphic; and 12 ISSR primers amplified 113 bands with 52 (46.02%) polymorphic. Both RAPD and ISSR analyses revealed a low level of genetic diversity in wild populations of O. granulata. Furthermore, analysis of molecular variance (AMOVA) was used to apportion the variation within and between populations both within and between regions. As the RAPD markers revealed, 73.85% of the total genetic diversity resided between the two regions, whereas only 19.45% and 6.70% were present between populations within regions and within a population respectively. Similarly, it was shown by ISSR markers that a great amount of variation (49.26%) occurred between the two regions, with only 38.07% and 12.66% between populations within regions and within a population respectively. Both the results of a UPGMA cluster, based on Jaccard coefficients, and pairwise distance analysis agree with that of the AMOVA partition. This is the first report of the partitioning of genetic variability within and among populations of O. granulata at the DNA level, which is in general agreement with a recent study on the same species in China using allozyme analysis. Our results also indicated that the percentage of polymorphic bands (PPB) detected by ISSR is higher than that detected by RAPD. It seems that ISSR is superior to RAPD in terms of the polymorphism detected and the amplification reproducibility. Received: 29 March 2000 / Accepted: 15 May 2000  相似文献   

20.
Molecular characterization of Tulipa L. species can elucidate the relationships among the species and provide more information about the taxonomy of this valuable genus. In this study, the genetic relationship among 39 Tulipa accessions from Khorassan and Yazd Provinces, located in east and northeast Iran, were analyzed using inter-simple sequence repeat (ISSR) primers. Ten selected ISSR primers from 20 screened primers generated a total of 97 polymorphic DNA bands. Unweighted pair-group method of cluster analysis based on Dice similarity values separated the accessions into nine groups. Seven species were recognized within these groups, and T.?micheliana Hoog was the most frequently encountered species. The subgroups formed within both T.?micheliana and T.?lehmanniana Merckl. revealed a low level of diversity within these species. T.?biebersteiniana Schultes & Schultes fil. and T.?biflora Pallas accessions made a separate clusters. The grouping of accessions was generally consistent with principal coordinate analysis (PCA) and clearly showed the position of species in the subgenera and sections of Tulipa. These results clearly showed the usefulness of DNA fingerprinting for identification of Tulipa accessions, and it is imperative to collect and characterize more genetic variability from the other distribution areas of this genus.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号