Pre and post-infectional antimicrobial substances in tobacco leaves

Abstract

Tobacco. (Nicotiana tabacum L.) plants were inoculated with the incompatible pathogen Pseudomonas syringae pv. pisi by the leaf infiltration method and the inoculated leaf tissue extracted 24 h after inoculation by using the facilitated diffusion technique. This extract showed to contain antimicrobial activity in biossays against test organisms. In less extent, extracts obtained from intact leaves, water infiltrated leaves and symptomless tissue adjacent to tissue showing hypersensitive  response also presented antimicrobial activity against some test microrganisms.