The Photodynamic Action of Methylene Blue on the Virus of a Plant Disease

Abstract

The results of the author's experiments very briefly described in this note are interpreted to indicate that the virus of maize streak [R.A.M., xiv, p. 146] is inactivated by adding to it sufficient methylene blue ('medicinale' of Meister Lucius and Brüning) and then irradiating the mixture for 3 to 4 0.5 hours in diffused daylight at an open window [ibid., xiv, p. 186]. The virus agent was not inactivated, on the other hand, when the virus plus methyiene blue mixture prepared in a dark room was kept for a similar period in total darkness, or when the virus fluid alone was irradiated as in the first series. These results are correlated with recent work by Perdrau and Todd [loc. cit.] on animal viruses as well as on certain races of bacteriophage.