جستجوی مقالات مرتبط با کلیدواژه « issr markers » در نشریات گروه « بیوتکنولوژی و ژنتیک گیاهی »

Orchard Grass (Dactylis glomerata L.) is a perennial forage and cross-pollinating grass, has wide genetic distribution in Iran. Although the genus Dactylis has been studied quite well within the past decades, little is known about the genetic diversity and population patterns of natural populations in grassland regions. The aim of this study is to identify the genetic diversity of this species in the East Azerbaijan, Iran.

In this study, seeds of 25 ecotypes of Dactylis glomerata L. were planted in the research farm of the Agricultural Biotechnology Research Institute of Iran, Northwest & West region in Tabriz as a randomized complete block design with 3 replications. Then 34 selected genotypes (single plant) were examined using 22 ISSR markers.

According to the results of ISSR markers, a total of 424 loci were amplified in the genome, of which 34 loci among all studied genotypes were monomorphic and 390 loci were polymorphic. The mean percentage of polymorphisms for D. glomerata L. in ISSR markers was estimated to be 70.39%. Also, the mean PIC value (polymorphic information content) for ISSR markers was equal to 0.288, the minimum PIC value for ISSR14 marker (0.175) and the maximum PIC value belonged to ISSR22 marker (0.341). Grouping of D. glomerata L. genotypes based on ISSR markers was performed using Mega 4.0.2 and Structure software, which grouped the results of Mega 4.0.2 genotypes into 4 groups, and Structure software grouped the genotypes into 2 groups.

The results indicate that the using of ISSR markers to differentiate close kin populations has a high advantage and plays a significant role in the differentiation of individuals. Also, the high allelic diversity of ISSR markers indicate a large level of diversity in D. glomerata L. populations and it’s a suitable tool for studying the genetic diversity of D. glomerata L.

In breeding programs, it is necessary having knowledge of the relatedness and genetic diversity in germplasm pools. The spread of cultivated regions and the high levels of production indicates citrus importance in the global economy. Therefore, 110 citrus genotypes were evaluated using 12 ISSR markers. Overall, 154 polymorphic bands were scored with an average of 12.8 alleles per primer. The polymorphism percentage ranged from 57 for the ISSR1 to 82 for the ISSR9. Averages of polymorphic information content (PIC), marker index (MI), gene diversity index (Nei), Shannon index (I) and number of effective alleles (Ne) were 0.48 ± 0.002, 6.14 ± 1.17, 0.42 ± 0.11, 0.61 ± 0.12 and 1.78 ± 0.27, respectively. Based on genetic diversity statistics, the studied population had high genetic diversity, and four markers (ISSR11, ISSR9, ISSR4, and ISSR5) had more potential for differentiation of genotypes. Cluster analysis and model-based structure analysis, divided the genotypes into five groups and four subpopulations based on the Neighbor-Joining method (NJ) and Bayesian approach, respectively. Based on both analyses, grouping of unknown genotypes and control cultivars in the same group probably confirms the assumption of a common genetic background between these genotypes. Results from the two analyses showed that Pummelo (C. maxima), Mandarin (C. reticulate), and Citron (C. medica), as three true citrus species, separated in different groups. In addition to the three true species, at least one species or another genus of citrus relatives is involved in the genetic makeup of the studied population. In this study, although both used analyses were effective in completing each otherchr('39')s information, by considering the degree of genetic mixing and the information of the origin of the genotypes, the effectiveness of model-based structure analysis in evaluating genetic relationships could be achieved.

In the present study, in order to evaluate the drought tolerance indices and their relationship with ISSR markers, 12 rapeseed genotypes were studied using a factorial experiment based on completely randomized block design under the three irrigation treatments (control and irrigation after drainage of 60 and 85% moisture content) in the greenhouse of Mohaghegh Ardabili University, Iran. Drought tolerance genotypes were evaluated by quantitative indices including MP, GMP, SSI, STI and TOL. Cultivars in all five of indices at two levels of stress exhibited significant differences. Regarding the results of the mean comparison at both levels of stress, SLMO46 was identified as the most resistant cultivar with the highest amount of MP and STI, and Karun was the most sensitive one with the highest amount of SSI index. According to the results of factor analysis, in the first level of stress, Sarigol32 and Karun were sensitive, and in the second level of stress, Talaye and Sarigol32 were sensitive as well. SLMO46 was known to be resistant to stress in both levels of stress. Phenotypic correlation of grain yield under stress and non-stress conditions was investigated in two levels of stress with 5 drought indices. In first level of stress condition, grain yield had a positive and significant correlation with mean productivity, geometric mean of productivity and stress tolerance index. In the second level of stress condition, the same correlation was observed with the difference that there was no significant correlation between drought tolerance and tolerance indices. Canonical correlation analysis was performed between drought indices and molecular markers. Five ISSR primers (5, 9, 11, 14 and 19) with the highest polymorphic percentages were used for calculation using the first factor coefficients. ISSR-PCR was used to identify some of the molecular markers associated with drought tolerance indices. A total of 106 clear and score-able loci were amplified by 18 ISSR primers, of which 60 bands (56.6%) were polymorphic. Finally, according to the results, these markers can be used in rapeseed breeding programs for drought tolerance.

Barley (Hordeum vulgare L.) is a model plant for genetical and physiological studies and has a high adaptability to different conditions. In order to locate QTL, the genomic areas controlling barley agronomic traits under experimental conditions were conducted in 104 families with their parents (Badia and Kavir) in the Research Farm of Gonbad-e-Kavous College in 2013-2014. Agronomic traits such as biomass, spike weight, spike number, spike length, grain yield, peduncle length, stem diameter, flag leaf length, flag leaf width, flag leaf weight, grain numbers, grain weight, and awn length for all families were measured. For the saturation of map, 19 (93 alleles), the ISSR marker used that assigned to 7 groups of attachment to 7 chromosomes with a genome length of 617.5 cM and the average between markers equal to 5.41 cM Morgan. A total of 21 locations with QTL were identified for the agronomic traits. Thirteen major effect QTLs that controlled a large proportion of phenotypic variation were identified. Major QTLs The effects of controlling the desired attributes and their linked markers can be used in selection programs using the marker.

Sugar beet is one of the most important plants playing a key role in human food production in the world. Sugar beet has nutritional value as rice, corn, wheat, potato and beans. The estimation of genetic diversity of plant material is the first step for identification, conservation of genetic resources and designing of breeding programs. In order to study the genetic diversity of 20 sugar beet genotypes, 20 ISSR primers were used. After DNA extraction and PCR amplification, using ISSR primers the scores (0 and 1 for absent and present band, respectively) of resulting bands subjected to statistical analyses. Genetic diversity indices of ISSR markers in the studied sugar beet genotypes showed that UBC853 and UBC847 had the highest (0.38) and lowest (0.13) values of polymorphism information content respectively. Also UBC830 locus had the highest rate (4.32) of Shannon diversity index, which represents the genetic diversity among populations, whereas UBC847 had the lowest (0.58) Shannon index. Cluster analysis based on molecular data using Jaccard's similarity coefficient and UPGMA method, classified the sugar beet genotypes into four major groups. Based on the results of principal components analysis, the first three principal components explained 72.67, 5.99 and 4.05 percent of total (82.72%) total variation indicating ISSR markers have good distribution in the whole genome. The classification of the sugar beet genotypes based on the first principal components, had similarities and differences with cluster analysis. Results of this study can be used in breeding programs of sugar beet.

The genus pumpkin from the family Cucurbitaceae with oily seeds has 10 species, 5 of which are ofagricultural importance. Three species C. Pepo and C. Moschata, C. Maxima are more important. The presentstudy aimed to investigate genetic diversity based on ISSR markers in 30 genotypes of 3 populations ofpumpkin. For this purpose, 4 primers with simple repetitive sequences (microsatellite) were used. In this study,72 genetic locations were ranked, of which there were 72 polymorphic locations with a polygonal percentageof 100%. To assess the genetic similarity between the population, cluster analysis using Jaccard's similaritywas used with UPGMA method. The mean genetic distance of genotypes (by Jaccard's coefficient of similarity)was 0.77 and the mean of content (PIC) was 0.47. The ISSR11 primers had the highest PIC (0.50). With theregret to dendrograms obtained from cluster analysis revealed a high variation among genotypes. The highestgenetic distance was between genotypes R30, R11 and R14 and the lowest genetic distance between R24 andR27. The results of this study showed that ISSR markers can be effectively used to study the genetic variationof pumpkin. Among the primers used, the marker ISSR11 ((GA) 8 G) was the most suitable primer forsubsequent studies.

Iran is known as one of the most important pear genetic resources because of being near to the pear diversity centers and having more than 10 species of genus Pyrus. On the other hand, Iran with acreage of 17,000 hectares, is one of the pear production centers. Despite its unique geographical location, there is no sufficient genetic information among pear germplasm in Iran and it is not clear what genetic relationship is between Iranian local genotypes and imported genotypes. In this study, Inter Simple Sequence Repeat (ISSR) markers was used for clustering of 10 Iranian Pear genotypes and positioning of their genetic variation among 13 imported genotypes. Fifteen ISSR primers were screened that yielded a total of 257 amplified products, of which 213 bands (81.6%) were polymorphic. Dendrogram of pear cultivars with ISSR banding patterns was drawn with NTSYS V. Pc-2.02e software using Dice coefficient and UPGMA (Unweighted Pair-Group Method Arithmetic Average), method. The 23 genotypes of pear were clustered in to three groups. The first group includes Conference, Mohammad Ali, Sardroudi, Bartlett, Red Bartlett, Harrow Sweet, Pass Crassane, Doyenneducomice, Anjou, Palestine,Lies Bonne, Duchesse and Daregazi. Kolikhaj, Sebri, Khuj labtorsh, Dom kaj, Khuj Katesar, Khuj Mordab Anzali and Shah Miveh belong to the second group. The third group includes SK10 and SK13. Cultivars were classified according to the geographical origin and the figures belonging to P. communis and P. pyrifolia, were completely separated. Iranian commercial cultivars including: Dom kaj, Shah miveh, Sebri with different Khuj accessions were placed in a group, that seems that thay have originated from different Khuj. While the three cultivars: Mohammad Ali, Sard roudi and Daregazi revealed closer to the European figures and possibility they have different origin than different Khuj And have a common ancestor with European figures. The results of this study indicate that ISSR markers have higher level of discrimination in evaluating genetic diversity and fingerprinting of pear genotypes.

Orobanche spp. is holoparasitic plant, parasitising roots of different crops. Genetic polymorphism was investigated among and within 3 Orobanche species collected from different regions of northwest Iran, using ISSR markers. Out of 34 ISSR primers tested, 20 were found to be polymorphic and produced clear bands. 261 discernible bands were generated with 254 (94%) being polymorphic. Among studied species, "O. aegyptiaca" showed 2 unique bands. Clustering algorithm was divided collected Orobanche specimens into 6 main groups. It was obvious that genetic relationships among studied landraces did not have force tendency to associate with their geographic origins. According to AMOVA, 100% of the total variation was partitioned within species. Such variability is important for any attempt to develop resistant host crops against parasite.