Identification of genetic distances and heterotic groups of inbred maize (Zea mays) lines using DNA fingerprinting

[摘要] English: AFLP (Amplified Fragment Length Polymorphism) analysis has found widespreaduse in DNA fingerprinting because of its relative simplicity, low cost and highmarker output. AFLP analysis also does not have the limitations associated withmorphological characterisation and the use of other molecular markers such asRFLP's (Restriction Fragment Length Polymorphisms) and RAPD's (RandomAmplified Polymorphic DNA markers). Furthermore, the AFLP technique hasfound widespread use in the identification of cultivars, varieties and breedinglines. The accurate identification of breeding material is extremely important, notonly for the protection of breeder's rights, but also to accelerate plant-breedingprogrammes. The aim of this study was to use AFLP fingerprinting for theidentification and genetic distance analysis of a collection of maize inbred linesfrom the Advanta Africa genebanks.Fifty maize inbred lines from Africa (local), Argentina, Zimbabwe (CIMMYT),Garst (USA) and Thailand were fingerprinted using AFLP's. A total of 107scored AFLP loci were used to calculate pairwise genetic distances. This revealedan average genetic distance of 4.38% between all lines studied. The trend of theclustering pattern was more variation in the major clusters with less variationbetween lines in subgroups and even less variation within the minor groups. Itwas also further illustrated that the local and foreign inbred lines were not groupedseparately. Neighbour joining cluster analysis of the genetic distance data yieldeda dendogram that indicated the absence of relation between geographic diversityand genetic diversity.The resulting knowledge of genetic distance and identification of maize inbredlines in this study will contribute towards maize breeding programmes in AdvantaAfrica Seeds. It permits an organisation of germplasm resources and identificationof parents for crossing blocks. This will enable the breeder to make morescientific based choices, where both additive and non-additive sources of geneticvariation contribute to the gain. Our results have shown that AFLP technology is arapid, informative and precise technique for identification of maize inbred lines inthis study

[发布机构] University of the Free State