Effect of blasticidin S on hypersensitive death of potato leaf petiole cells caused by infection with an incompatible race of Phytophthora infestans

Abstract

The effect of an inhibitor of protein synthesis, blasticidin S, on the infection process of an incompatible race of Phytophthora infestans was studied in cut surface cells of potato leaf petiole tissue. Ten parts/10 6 of blasticidin S applied to the host tissue 0·5, 1·0 and 1·5 h before inoculation did not affect the time required for penetration of the host cell wall by the parasite and the growth rate of intracellular hyphae. The time elapsing from penetration to the hypersensitive death of the infected host cell was not affected by treating the potato cells with 10 parts/10 6 of blasticidin S 1·5 h before inoculation. Incorporation of 3H-leucine into the acid insoluble fraction of potato petiole tissue showed that protein synthesis was strongly inhibited by the blasticidin S treatment. These results suggested that de novo protein synthesis does not play an important rôle in the processes leading to hypersensitive death of potato cells caused by infection with an incompatible race of P. infestans.