جستجوی مقالات مرتبط با کلیدواژه « aflp » در نشریات گروه « آب و خاک »

Studying genetic diversity is important because a decrease in genetic variability might result in a reduction of the plasticity of the crops to respond to changes in climate, pathogen populations, or agricultural practices. In this study, 72 Sardari wheat (Triticum aestivum L.) ecotypes were analyzed by AFLP markers and 17 phenotypic characters. Three pairs of EcoRI/MseI primer combinations produced 1582 polymorphic bands (with mean percentage of polymorphic 73.92%). Cluster analysis using Jaccard coefficient and the entire AFLP data divided all ecotypes into eight major groups. Mean, coefficient of variation, phenotypic, genotypic and environment variance were calculated in each quantitative character. Cluster analysis using Euclidian distance through the quantitative characters divided all ecotypes into six major groups. Comparison of genetic distances obtained from AFLP and agronomic data showed low correlation between the two diversity measurements (0.02). The results showed a high degree of genetic diversity between the Sardari ecotypes, suggesting that Sardari is not a single cultivar, but it is the mass of ecotypes and could be introduced in the gene bank.

Genetic maps with high genome coverage are becoming increasingly useful in both basic and applied genetic researches. In the last decades, the advent of DNA markers has brought about a magnificent revolution in the production of genetic map, especially in wheat. In the present study, AFLP markers were used to saturate linkage map of 107 doubled haploid individuals produced through Fukuho _Komugi × Oligo – Culm crosses received from Japan International Research Center of Agricultural Science (JIRCAS). The framework of genetic map was used as base map for next analysis. AFLP analysis was performed with MseI / PstI as digestive enzymes. The average percentage of polymorphism with AFLP markers was around 16.6%. Data analysis was performed by computer program known as Mapmaker / EXP, Ver. 3.3. In this program, the maximum distance criterion was 50 cM and the minimum LOD equated 3. The drawing of chromosome schema for the linkage groups was performed by Draw map, Ver 1.1. In this analysis, 115 AFLP markers were divided into 10 groups in addition, some of the markers remained unlinked. The supplementary data analysis along with specific SSR markers identified the chromosome loci of the markers. Ultimately, 71.1% of the markers were assigned to genome A, 16.5% to genome B and only 3% to genome D. The AFLP markers filled 11 gaps in 7 chromosomes (2A, 3A, 7A, 2B, 3B, 5B and 7B). The low coverage of genome D was due to the limited polymorphism and its conservation in different populations. Among the chromosomes, maximum number of markers (60) was assigned to the chromosome 7A. The distribution of the markers on this chromosome was not uniform. Such a distribution was related to the grouping AFLP markers within heterochromatin region, particularly around the centromere.

Formation of the two- and six-rowed types in barley is predominantly controlled by alleles at a single locus (vrs1) which is located in long arm of chromosome 2H. This gene is a key character on the study of barley domestication and yield. Near-isogenic lines (NILs) of barley were produced from crosses between Kanto Nakate Gold (tow-rowed) and Azumamugi (six-rowed). The selected lines were used for screening of AFLP polymorphic bands which are linked to vrs1 locus. After screening of a total of 1792 primer combination, five polymorphic bands were identified. A construction of high resolution map around the vrs1 locus was made using recombinant inbred lines. These markers can be used for a map-based cloning of the genes at the vrs1 locus.