Determinación de la concentración mínima inhibitoria de Glufosinato de amonio en callos organogénicos de Phaseolus vulgaris L cv. `CIAP7247F'

An efficient selection system is necessary for distinguishing transformed cells of the untransformed tissue. This study aimed to determine the minimum inhibitory concentration of the herbicide Ammonium glufosinate in organogenic calli of Phaseolus vulgaris cv. CIAP 7247F, to use it as a selective agent in the process of genetic transformation . Fragments (4-5 mm) of proliferated calli after second subculture were used as explant. Callus proliferation medium with different concentrations of Ammonium glufosinate (0.10, 0.20, 0.30, 0.40, 0.50 and 0.60 mg l -1 ) was employed. At eight week of culture, the number of necrotic calli and the percentage of callus mortality were scored. Moreover, the damages caused by the selective agent in treated calli were described. All studied concentrations of Ammonium glufosinate produced necrosis in calli of P. vulgaris cv. CIAP7247F. The increase of Ammonium glufosinate concentration in the proliferation culture medium increased the percentage of necrotic calli. With concentrations of 0.50 and 0.60 mg l -1 of the selective agent, 87.5% and 93.8% of the calli showed complete necrosis respectivity. Base on previous observations a descriptive scale of degree was designed to evaluate the affectations provoked by the selective agent in common bean calli. Finally, 0.5 mg l -1 of Ammonium glufosinate was selected as the minimum inhibitory concentration because more than 87 percent of the calli necrotic within 8 weeks of cultivation. Key words: bar gen, beans, callus, selective agent.