Disease Resistance in Coffee Berries Reversible Susceptibility Induced By Metabolic Inhibitors

Abstract

Mature green berries of Arabica coffee normally are resistant to fungal attack except by a virulent strain of Colletotrichum cofJeanum Noack. Disease resistance in many plants has been explained by the responsive production by the host of an anti-fungal substance, termed a phytoalexin (Muller 1961); only after stimulation by attempted injection. This implies that the host responds with an active, dynamic, metabolic conversion of biochemical precursors into the compounds which inhibit development of the attempted infection. Such a process has been demonstrated in a number of host-parasite combinations and the active principles have been isolated and assayed (Cruickshank 1963, review).