Estimation of Genetic Diversity among Thirty Bread Wheat Varieties by RAPD Analysis

Abstract: RAPD markers were used to fingerprint thirty hexaploid wheat varieties (Triticum aestivum L.) from different genetic background. A total of 76 DNA fragments were amplified, using five primers, ranging in size from 1884 to 200 base pairs. Out of the 76 amplified products, 19.7% were monomorphic and 80.3% were polymorphic, averaging 12.2 polymorphisms per primer. The number of DNA fragments for each primer varied from 9 (OP-B14) to 20 (OP-C15) with an average of 15.2 fragments per primer. One specific marker out of 11 amplified fragments was detected for primer OP-B11 and two specific markers out of 9 amplified fargments were detected for primer OP-B14. The genetic similarity between varieties ranged from 32 to 97%, with an average of 64.5%. The large genetic diversity may be due to the different areas from which the genotypes were collected. Some distinctive varieties showed high genetic similarity with other varieties, such as Sids1 and Sids 8 (97%), Sids 7 and Icarda 46 (96%), Icarda1 and Gimeza 9 (95% ). On the contrary, some varieties displayed low genetic similarity such as Giza164 and Sakha 60 (32%). The similarity values showed clearly substantial differences among the wheat varieties. The dendrogram resulting from the UPGMA cluster analysis showed that the studied varieties could be divided into two main clusters from the same node. The first cluster contained ten varieties four of them are Egyptian, while the second cluster contained 19 varieties including 13 Egyptian. The dendrogram clustered the genotypes into ten groups and showed efficiency in identifying genetic variability. The results indicated that RAPD analysis is useful as molecular genetic marker for estimating the genetic diversity between wheat varieties

© 2007, INSInet Publication Identification and Prediction of the Flour Quality of Bread Wheat by Gliadin Electrophoresis

Abstract: Gliadin proteins were used to identify and characterize 30 wheat varieties. SDS-PAGE of gliadins revealed a total of 30 bands ranged from 74.5 to 6.5 kDa, where the number of total bands varied between varieties. The region of omega-gliadin had a wide range for a number of bands. Among gliadin protein bands, nine bands were monomorphic and 21 bands were polymorphic, which were used to characterize the wheat varieties. The similarity index and dendrogram demonstrated the genetic relationships among wheat varieties using the gliadin protein bands resulted from SDS-PAGE analysis. In the studied Egyptian wheat varieties, the gliadin band of ã-45 related to high gluten quality, while the ù-38 band related to moderate gluten quality. However, it was found that ã-42 band related to low gluten quality. The concentration of each gliadin protein subgroup was varied among the wheat varieties and some of gliadin subgroups were related partially to gluten quality in some varieties. The obtained results indicate that gliadin proteins analysis is useful as biochemical genetic markers for characterizing the wheat varieties and detecting flour quality

Cytogenetic and molecular responses of ammonium sulphate application for tolerance to extreme temperatures in Vicia faba L.

Effects of ammonium sulphate [(NH4)(2)SO4] on mitosis, cell cycle and chromosomes in Vicia faba L. seeds exposed to extreme temperatures were investigated using flowcytometric and cytogenetic analysis. Seeds germinated at high and low temperatures showed a significant decrease in mitotic index as compared to those of optimum temperature conditions. Application of 50 and 1000 mu M (NH4)(2)SO4 were successful in alleviating the negative effects of low and high temperature on mitotic activity, respectively. 50 mu M (NH4)(2)SO4 showed the most positive effect on cell cycle at the extreme temperatures. This concentration increased the cell division removing or decreasing the negative effects of temperature stress. Namely, the highest G2/M and S phase percentages under stress conditions were obtained with application of 50 mu M (NH4)(2)SO4. Chromosomal aberrations were not observed in cells of seeds germinated in distilled water and also at any temperatures. However, the frequency of chromosomal aberrations increased significantly by increasing (NH4)(2)SO4 concentration. The highest aberration frequency in all temperature degree tested was found at 1000 mu M (NH4)(2)SO4 concentration.Department of Scientific Research Project Management of Suleyman Demirel University (SDUBAP)Suleyman Demirel University [1636-YL-08]The authors thank the Department of Scientific Research Project Management of Suleyman Demirel University (SDUBAP) for the financial support of the project SDUBAP (1636-YL-08). Thanks also to Dr. Gulderen Yanikkaya DEMIREL and Mehtap OZDEMIR (Istanbul Centro Laboratory Flowcytometry Department, Istanbul, Turkey) for its help in flow cytometric study