The Effects of Pharmacological Carbonic Anhydrase Suppression on Defence Responses of Potato Leaves To Phytophthora Infestans

Abstract

SUMMARYIn this study we proposed carbonic anhydrase (CA) as an important element of basal resistance during the potato (Solanum tuberosum L.)-Phytophthora infestans interaction. We found a different β-CA expression pattern in incompatible vs. compatible systems correlated in time with CA enzyme activity. Resistant potato leaves supplied with dorzolamide (an inhibitor of carbonate CA activity) and challenged with the pathogen showed an elevated nitric oxide (NO) synthesis, which was the most evident during the early phase of NO burst (at 3 hpi) during hypersensitive response (HR). In vitro application of dorzolamide and effective inhibitors of NO synthesis confi rmed the implication of CA activity in NO metabolism during potato defense. To clarify how suppression of CA carbonate activity translates into the complexity of NO-related responses leading to potato resistance or susceptibility to an oomycete pathogen we analysed expression of NPR, PR1, and PAL.Taken together, pharmacological damping of CA activity revealed a functional link between CA and NOdependent signaling in potato defense against P. infestans manifested by accelerated NO formation and a modifi ed salicylic acid defense pathway. The dorzolamide-mediated effective responses for basal resistance also delayed symptoms of late blight in the susceptible potato cultivar, without overcoming HR formation in the resistant one.