Use of RAPD markers in plant varietal development.

摘要

DNA based molecular markers have played an important role in plant varietal development. With the discovery of polymerase chain reaction (PCR), very low or single copy sequences can act as molecular markers because during the PCR, DNA is multiplied to such an extent that it can be easily visualized on an agarose gel. With the new technique of random amplification of genomic DNA, there is no need to know the target DNA sequence, and specific primers and ample polymorphism can be revealed.;Rye (Secale cereale L.) contains agronomically important genes that have been transferred to wheat through chromosomal translocations. Extensive polymorphisms were observed among six varieties of rye, Balboa, Blanco, Chaupon, Imperial, Insave and Musketeer by random amplified polymorphic DNA (RAPD) markers. In addition to the varieties, amplification patterns of individual plants were also studied.;Rye chromosome 1RS containing wheat lines were studied by random primers to find markers specific for rye translocation. Hexaploid wheat lines carrying 1RS.1BL translocation in Chisholm and Arkan background, 1RS.1AL translocations and 1RS.1BL translocations in tetraploid wheat were analyzed. Two 1RS specific markers, OPR19;RAPD markers have the potential to identify plant varieties, species and hybrids. Species specific amplification profiles for 17 rhododendron species, hybrids and varieties were produced. The amplification patterns were stable among clonally propagated rhododendron species, but when F2 plants of two hybrids were studied with RAPDs, extensive polymorphisms were observed among individual F2 plants. The stability of RAPD profiles among clonally propagated rhododendrons and polymorphisms among F2 hybrids describes their usefulness in plant identification and genetic studies.;Amplification profiles of thirteen rhododendron hybrids, species and varieties were analyzed to study their genetic relationship. In the cluster analysis, the hybrids with common parents grouped together and showed a close association as compared to the others. The overall genetic relationship revealed by cluster analysis was consistent with their known pedigrees.