EMBRYOGENIC CAPACITY OF INDUCED CALLI ON ZYGOTIC EMBRYONIC AXIS OF Agave angustifolia Haw

Abstract

By using zygotic embryonic axis from seeds of agave mezcalero (Agave angustifolia Haw) as explants, it was possible to induce embriogenic calli in vitro, and from these calli we obtained somatic embryos (SE). Two concentrations of the Murashige and Skoog (MS) medium were used, 25 and 100 % concentrations (MS-25 and MS-100) combined with 0.0, 1.0, 2.0 and 3.0 mg L^-1 of 2,4-dichlorophenoxiacetic acid (2,4-D), with 0.0 and 1.0 mg L^-1 of 6-benzyladenine (BA), and 30 and 60 g L^-1 sucrose. Cultures were incubated either under 16 h light (38 μmol m^-2 s^-1) and 8 h dark, or kept in complete darkness, for a total of 80 treatments. Callus formation was detected 4 days (d) after beginning the culture (DABC) under light conditions and 5 d in dark conditions, independently of the treatment, except where plant growth regulators (PGR) were not added and in those supplemented only with BA. SE formation was observed at 100 DDIC; this process was favored in embryogenic calli induced with MS-25, 60 g L^-1 of sucrose, 3.0 mg L^-1 of 2,4-D and 1.0 mg L^-1 of BA, and complete darkness. All SE germinated on the MS-50 medium supplemented with 60 g L^-1 sucrose and 8 g L^-1 agar, without PGR. With this protocol it is posible to regenerate complete plants of A. angustifolia in140 DABC.