Biochemical Responses of Suspension-cultured Sugarcane Cells to an Elicitor Derived from the Root Pathogen Pachymetra chaunorhiza

Abstract

The fungus Pachymetra chaunorhiza Croft & Dickcauses a root rot in sugarcane (Saccharum interspecifichybrid). Suspension-cultured sugarcane cells prepared from cultivars Q114(P. chaunorhiza resistant) and Q90(P. chaunorhiza susceptible) were inoculated with aheat-derived elicitor preparation from P. chaunorhizaand the cellular responses monitored by measuring phenylalanine ammonia-lyase(PAL) and peroxidase (POD) activity and the production of additional phenoliccompounds.

Introduction of the P. chaunorhiza elicitor inducedmarked changes in the biochemistry of both sugarcane cell lines. Both celllines produced additional phenolic compounds not present in untreated cellsand different compounds were produced by each cell line. Induced enzymeactivities also differed between the cell lines with Q90 (susceptible) showinga large and transitory increase in PAL activity that was far greater than thatobserved for Q114 (resistant). POD activity increased more in Q114 than inQ90, although the differences between the resistant and susceptible cell lineswere not as great as for PAL.