Effect of Light on Tobacco Mosaic Virus Formation under Anaerobic Conditions

Abstract

Tobacco leaf discs, infected with tobacco mosaic virus (TMV), were floated on Vickery's solution and kept under N2 in the light, conditions where the only source of ATP was assumed to be cyclic photophosphorylation. Usually the virus content was unaltered or decreased during the next 24 hours; occasionally there was some TMV formation, but less than in air and light, and it was abolished by 10−5 M DCMU. This suggested that ATP produced by cyclic photophosphorylation was not used in TMV formation. Infected discs exposed to N2 for longer than 2 hours formed less virus when transferred to air and light than discs not exposed to N2, presumably because some breakdown in the TMV‐forming apparatus occurred in ATP deficient conditions.