Inhibiting Effects of Resveratrol and Its Glucoside Piceid against Venturia inaequalis, the Causal Agent of Apple Scab

Publisher Website
Google Scholar
Abstract
Resveratrol is a phytoalexin produced in different unrelated plant species such as grapevine and peanut. The effect of resveratrol and its glucoside trans-resveratrol-3-O-β-d-glycopyranosid (piceid) against Venturia inaequalis, the causal agent of apple scab, was evaluated using a newly established test based on enzymatically isolated cuticular membranes (CMs) from apple (Malus domestica Borkh.) leaves. The test substances resveratrol and piceid were either sorbed to CMs before inoculation with spores or were applied simultaneously with the Venturia inaequalis spores to the CMs, and their effect on germination, appressoria formation, and penetration was examined. Resveratrol had no influence on spore germination but a significant inhibiting effect on penetration when applied simultaneously as well as before. A percentage inhibition of 89.7 ± 11.5 and 61.8 ± 35.1 was observed for simultaneous and preapplication, respectively. The resveratrol glucoside piceid had a significant inhibitory effect on germination and completely inhibited penetration of the fungus at concentrations between 200 and 400 μg mL-1 when applied simultaneously with the spores to the CMs. On piceid-enriched CM (preapplication), spores germinated but penetration was inhibited nearly completely (96.1 ± 5.1%). Thus, in vitro experiments showed that resveratrol and its glucoside in fact could contribute to improving the pathogen resistance of apple leaves. Keywords: fungal pathogen; isolated cuticular membrane; penetration; phytoalexin

This publication has 22 references indexed in Scilit: