Actinomycin D Inhibition of the Zinc-induced Formation of Cytochrome c in Ustilago

Abstract

Agrobacterium tumefaciens B-6 and T-37 strains, inoculated into Nicotiana glauca, N. langsdorffii, and their interspecific hybrid, which forms genetic (spontaneous) tumors as well, initiate amorphous tumors from the B-6 strain and organoid tumors (aberrant roots, stems, and buds) from the T-37 strain. In the hybrid, the critical point was to induce crown gall tumors at the site of wounding and not spontaneous genetic tumors. To succeed, this inoculation had to be made at a very early (5-6 leaf stage of development). It is observed that genetic organoid tumors readily formed at the nodes following flowering or leaf abscission. Furthermore, it was noted that genetic tumor derivatives are obtainable from hybrid pith callus or hybrid seedlings cultured in vitro.