Transformação de plantas.

ABSTRACT: During centuries mankind plants to obtain cultivars with superior characteristics. However, conventional methods of plant breeding present limitations. The development of transformation methods created possibilities of great progresses in plant breeding because it offers the opportunity to introduce exogenous genes into superior cultivars to obtain new varieties. Genetic transformation is the targed organism using non sexual methods. Transgenic plants can be defined as those the present genes different from the original genoma obtained by techniques of genetic engineering. The transformation stages consist of the identification isolation, cloning and introduction of gene into the cells. There are several transformation methods, and the choice depend on the species to be transformed, the type of the explant (cell, tissue, protoplasts) and the capacity of explant regeneration. Among the principal methods are: 1) transformation mediated by Agrobacterium; 2) biolistic; 3) eletroporation