Resveratrol production potential of grape flowers and green berries to screen genotypes for gray mold and powdery mildew resistance

Abstract

The ability of grape cultivars to produce resveratrol in response to UV radiation is associated with their resistance to fungal pathogens. In this study, we evaluated the UV-induced resveratrol production potential of grape flowers and green berries of 72 grape genotypes. Their ability to produce resveratrol in response to UV radiation was used to establish a selection criterion for screening genotypes for resistance to gray mold and powdery mildew. We quantified resveratrol in grape flower extracts from pre-bloom and early bloom flowers after exposure to UV radiation. There was a strong negative correlation between UV-induced resveratrol production and susceptibility to Botrytis infection. The grape genotype was considered to be susceptible to gray mold when the resveratrol content of whole flower clusters was less than 10 lg g -1 FW after the UV treatment. We determined resveratrol production in response to UV radiation in whole grape berries from 0 to 30 days after full bloom. The ability to produce resveratrol in response to UV increased by 8-to 20-times during this period, depending on the genotype. At 30 days after full bloom, Vitis vinifera genotypes generally had low levels of resveratrol (\50 lg g -1 FW), while interspecific hybrids, especially the North American cultivars, had high levels ([50 lg g -1 FW). There were clear varietal differences in resistance to Erysiphe (powdery mildew) infection. Susceptibility to Erysiphe infection was strongly negatively correlated with UV-induced resveratrol production.

In vivo localization at the cellular level of stilbene fluorescence induced by Plasmopara viticola in grapevine leaves

“…Despite the lack of direct evidence, the production of stilbenes was reported to correlate well with resistance levels to pathogens in Vitis species ( Chong et al , 2009 ). Therefore, the quantitative and qualitative (chemical) detection of stilbenes is used to screen disease-resistant genotypes in breeding programmes ( Pool et al , 1981 ; Jeandet et al , 1995 ; Gindro et al , 2006 ; Shiraishi et al , 2010 ).…”