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In Plant breeding, classical methods are not sufficient. Today new methods are used to introduce foreign DNA in to plant cells. Gene transfer into plant cells can be achieved by the natural process of gene transfer carried out by the bacterium “Agro bacterium tumefaciens”. These bacteria contain a larg plasmid, the Ti plasmid, Which is responsible for the induction of disease in wounded plants. It has become clear that the natural gene products of the T-DNA of Agro bacterium serves to either synthesize auxins and cytokinins or make the host cell more sensitive to auxins; this phenomena are known to be responsible for the production of the tumorous phenotype. T-DNA transfer and growth are encoded by different independent functions. T-DNA is also tranferred and integrated into the plant genome if the region responsible for tumour formation are depleted or inactivated. The most important vectors that have been developed are “cointegrative” and “binary” vectors. Three general procedures have been developed for the production of transgenic plant using Agrobocterium: Explant inoculation, protoplast co cultivation and seedling inoculation. However, the integration of foreign DNA plant cells by Agro bacterium is random and normally directed at the nucleus. There is evidence that T-DNA mediated gene can target plant chloroplasts. The natural gene vector system of “Agro bacterium tumefaciens” is restricted to the host range of Agro bacterium, Which includes dicotyledonous plants. However, Most monocotyledonous plants are not considered susceptibe and create difficulties. Many of these difficulties are removed and it can be expected that other problems will be overcome sooner or later.