A cytochrome P450 monooxygenase cDNA (CYP71A10) confers resistance to linuron in transgenic Nicotiana tabacum

The isolation of a Glycine max cytochrome P450 monooxygenase (P450) cDNA de signated CYP71A10 that. conferred linuron resistance to laboratory-grown, t ransgenic Nicotiana tabacum seedlings was previously reported. A nonsegrega ting transgenic N. tabacum line has been established that possesses two ind ependent copies of the G. max CYP71A10 transgene. Five-week-old progeny pla nts of this selected line were grown in a controlled environmental chamber and treated with linuron using either pretransplant incorporated (PTI) or p ostemergence (POST) applications. CYP71A10-transformed N. tabacum was more tolerant to linuron than the wild type for both application methods. The tr ansgenic N. tabacum line tolerated an approximately 16-fold and 12-fold hig her rate of linuron than wild-type N, tabacum when the herbicide was applie d PTI or POST, respectively. These results provide evidence char, plant-der ived P450 genes can be employed effectively to confer herbicide resistance to transgenic plants.