POLYMERASE CHAIN REACTION-BASED ASSAYS FOR THE CHARACTERIZATION OF PLANT GENETIC-RESOURCES

Plant genetic resources are an important component of biodiversity and provide the basic genetic variability that allow new and improved cul tivars to be developed. Numerous germplasm collections have been estab lished and it is important to establish that such collections are repr esentative and accessible to breeders and biotechnologists. Molecular markers provide the best estimate of genetic diversity since they are independent of the confounding effects of environmental factors. Assay s based on the polymerase chain reaction (PCR) are considered to meet both the technical and genetical requirements for the characterisation of plant and animal genetic resources. Two main approaches are descri bed, based on anonymous and defined primers. The use of both randomly amplified polymorphic DNA (RAPD) and microsatellites or simple sequenc e repeats (SSR) for the characterisation of perennial tree species, an d distribution of variability within gene pools is reported. The detec tion of interspecific gene introgression between coffee species with R APD markers is described together with the use of microsatellites to g enotype potato. The use of PCR-based assays will facilitate the evalua tion and utilisation of plant genetic resources.