التنوع الوراثي لبعض الانماط الوراثية للطماطة باستعمال واسمات الـ RAPD وSSR في العراق == Genetic Diversity of Some Tomato Genotypes Using RAPD And SSR Markers In Iraq
Author name:
اطياف جميل ثامر التميمي
Supervisor name:
علي حمود السعدي | محسن جلاب عباس
General topic:
Biology
Specific topic:
Plant - Genetics
Degree:
Doctorate
University:
University of Kufa - College Of Science - Department Of Biology
Language:
English
University location:
Najaf
First pages:
24T2936 - p.pdf
Abstract:
قدر التنوع الوراثي لـ 19 من الانماط الوراثية للطماطة (المحدودة وغير المحدودة النمو) المستزرعة في العراق باستخدام اثنين من واسمات الدنا (DNA Markers) المعتمدة على تفاعلات البلمرة المتسلسلة Polymerase Chain Reaction (PCR) وهما واسمات التفاعل التضاعفي العشوا | Genetic diversity of 19 tomato genotypes (determinate and indeterminate) cultivated in Iraq using two polymerase chain reaction based DNA markers (PCR based DNA markers); Random Amplified Polymorphic DNA (RAPDs) and Simple Sequence Repeats (SSRs).Variation of some growth criteria and morphological traits for each genotype were recorded in the growing season of 2012 - 2013.High variability was observed in plant height, leaf area, number of inflorescence, number of flowers and fruit weight among genotypes To achieve PCR reactions, total genomic DNA was isolated from fresh leaves (2 weeks old). The average yields of DNA were in the range of 100 - 295 ng/?l with a purity ranging between 1.8 - 1.9.RAPDs amplifications were performed for genotypes fingerprinting by testing 27 Operon primers. DNA polymorphisms among genotypes were scored within detectable amplified fragments (their numbers and molecular weight) after agarose gel electrophoresis and staining with ethidium bromide. The 27 primers produced 442 of main bands, out of which 312 were polymorphic bands (70.5%) and 70 were monomorphic (15.8%) across all tested genotypes.Each selected primer produced between 60 bands (OPA - 14) to 290 bands (OPD - 13). DNA amplification products ranged in their size from 250 bp (OPA - 01, OPU - 14, OPX - 15, OPX - 19, OPT - 08 ( to 2755 bp (OPX - 18). The highest number of polymorphic bands (21 bands) was produced by primer OPU - 03, while the lowest number of polymorphic bands (3 band) was produced by both primers OPA - 14 and OPB - 17.The primers varied in their capacity in producing polymorphic amplified profiles among tomato genotypes which individually reflected genotype specific DNA profiles (fingerprints). The most important primers for this purpose were primers that produced more variety specific DNA profiles, such as OPD - 13, OPT - 08, OPW - 04, OPA - 04, OPA - 15, OPB - 18, OPU - 03, OPC - 09.The highest value of discrimination among genotypes in this study was obtained by primer OPU - 03, while the lowest discrimination value was produced by both primers OPA - 14 and OPB - 17. The primer efficiency ranged from 0.13 in (primer OPC - 09) to 0.02 in (primer OPB - 17). The lowest genetic distance was 0.2294 between genotypes Oula and Shady lady, while the highest genetic distance was 0.9459 between genotypes Fotton and Special pack. Cluster analysis (Phylogenetic tree) by un weighted pair - group method of arithmetic means (UPGMA) based dendrogram revealed that they were two main genetic groups (major clusters).The first small major clusters included four (four genotypes) while the second large major cluster included (15 genotypes). A total of 21 alleles were detected among the tested genotypes using five SSRs loci distributed on four chromosomes of tomato. The molecular size of bands obtained from amplification of SSR products ranged from 121 to 247 bp. Alleles ranged from one in (Tom 8 - 9, Tom 41 - 42 and Tom 67 - 68 loci) to twelve in Tom 49 - 50 locus. The values of heterozygosity for each locus ranged between 0.63 for Tom 31 - 32 and 0.89 for Tom 49 - 50 with a mean value of 0.30. The polymorphic information content (PIC) values for the SSR loci ranged from 0.45 in Tom 31 - 32 to 0.58 in Tom 49 - 50 loci with an average of 0.21. Each one of (Tom 8 - 9, Tom 41 - 42 and Tom 67 - 68 loci) produce 0.0 value for both heterozygosity and PIC. The study revealed that, The lowest genetic distance was 0.3244 between varieties Tamara and W arda, while, the highest genetic distance was 0.9177between varieties Helam and Super marimond. The genetic similarity values ranging from 0.0823 to 0.6756 depending upon the genetic distance values that ranging from 0.3244 to 0.9177, indicating the largest diversity with percentage of 32 to 91% among the tested genotypes. The analysis of the results obtained from genetic distances and Neighbor - joining dendrogram (unrooted tree) revealed that, the 19 tested tomato genotypes can be grouped into two major groups : first cluster included nine varieties distributed in two subgroups. The second major cluster included 10 genotypes which in turn divided into two subgroups.The relationship among genotypes was not concern to their morphological characters and geographical origins. The overall analysis of the results show that both SSRs and RAPDs markers are powerful tools in fingerprinting and revealing the genetic relationships among tomato genotypes.
