ABSTRACT
Genomics extends genetic studies by considering the contributions of all or many of the genes in a plant. The rapid advancement of DNA technologies has allowed analysis of the entire genomes of some plant species. Many traditional molecular genetics approaches are now considered also to fall within the scope of genomics. For example, mapping of plant genomes becomes genomics because much larger numbers or all of the genes in a plant are analyzed. Genomics provides powerful tools for plant conservation of both wild populations and domesticated plants. The analysis of plant genomes has revealed variations at many levels: the size of the genome (DNA content), number of genes, number of copies of each chromosome or gene (ploidy), abundance and nature of repetitive elements, the relative positions of genes in the genome (comparative mapping), and codons or specific bases. The analysis of plant DNA at any or all of these levels can provide information on which to base better management of genetic diversity.
