Patent ID: 7592508

Claim:
A method of producing a transgenic cotton plant comprising the steps of: (a) obtaining cotton petiole explants, (b) exposing the petiole explants to a culture of Agrobacterium tumefaciens that harbors a vector comprising an exogenous gene and a selectable marker gene in medium that does not contain plant hormones and contains glucose as the sole carbon source, the Agrobacterium being capable of effecting the stable transfer of the exogenous gene and selectable marker gene to the genome of the cells of the petiole explant, (c) culturing the petiole explants on a medium containing one or more plant hormones and contains glucose as the sole carbon source to induce callus formation, wherein the one or more plant hormones is 2,4-dichlorophenoxyacetic acid at a concentration up to about 0.5 mg/l and kinetin at a concentration up to about 1 mg/l and wherein the pH of the medium is from 6.5 to 7.0, (d) selecting a transformed callus that expresses the exogenous gene on a medium that does not contain plant hormones and contains glucose as the sole carbon source, wherein the pH of the medium is from 6.5 to 7.0, (e) culturing the selected callus in suspension culture in a medium that does not contain plant hormones and contains glucose as the sole carbon source for a duration of about 10 days to about 14 days to induce formation of embryogenic calli, wherein the pH of the medium is from 6.5 to 7.0, (f) culturing the embryogenic calli on a medium that does not contain plant hormones and contains glucose as the sole carbon source to induce formation of embryoids, wherein the pH of the medium is 6.5 to 7.0, and (g) germinating an embryoid on a medium that does not contain plant hormones, contains glucose as the sole carbon source and contains a source of nitrogen selected from the group consisting of asparagine at an amount of about 200 mg/l to about 1 g/l, glutamine at an amount of about 500 mg/l to about 2 g/l and both asparagine at an amount of about 200 mg/l to about 1 g/l and glutamine at an amount of about 500 mg/l to about 2 g/l to obtain a young transgenic cotton plant, wherein the aspargine, glutamine or asparagine and glutamine replaces ammonium nitrogen in the medium and wherein the pH of the medium is 6.5 to 7.0.