Escherichia coli, source of the nptII gene which encodes a selectable marker enzyme, neomycin phosphotransferase II(NPTII) and is used to identify cotton cells containing the Cry1Ac protein and aad gene which encodes the bacterial selectable marker enzyme 3”(9) Oaminoglycoside adenyltransferase (AAD) allowing the selection of the Agrobacteria on media containing spectinomycin or streptomycin