Dependence of the level of phytoalexin and enzyme induction by fungal elicitor on the growth stage of Petroselinum crispum cell cultures

The extent of induction of some metabolic activities in cultured parsley cells (Petroselinum crispum) by an elicitor preparation from Phytophthora megasperma f. sp. glycinea varied with the growth stage of the cell culture. On the basis of cell fresh weight, the induction of phytoalexin accumulation was high until cell mass reached a maximum, and then declined to a low level which was indistinguishable from a level caused by an endogenous mechanism operating at this late growth stage. The induction of phenylalanine ammonia-lyase and 4-coumarate:CoA ligase activities by the elicitor showed a high degree of coordination and a sharp maximum preceding the stage of maximal cell mass. 1,3--Glucanase activity was induced to about the same level throughout all growth stages, with a large contribution by an endogenous mechanism at late stages.Abbreviations PAL Phenylalanine ammonia-lyase (EC 4.3.1.5) - 4CL 4-Coumarate:CoA ligase (EC 6.2.1.12)